BIO OCR A LEVEL AS + A2 + PRACTICAL TERMS
Lysis
'breaking'
Common vectors in genetic engineering
(Recombinant) bacterial plasmids, viruses
Factors affecting population size
(abiotic and biotic) limiting factors, migration (immigration and emigration), density dependent and density independent factors
The main seral stages of an ecological succession
(barren land) -> pioneer community -> intermediate community -> climax community
Vectors
(living/non-living) things that transmit pathogens from organism to organism
net gain of ATP from glycolysis
-2 used + 4 made = 2 net gain
resting potential value
-70mV
Adrenaline
...
Noradrenaline
...
how does a pregnancy test work?
1. wick dipped in urine, 2. urine travels up and hCG if present binds to monoclonal antibodies with colour markers, 3. if hCG present binds to fixed antibodies in first antibodies in first window to make a cross, 4. excess unbinded antibodies bind to different fixed antibodies regardless of hCG and create a line in second window to prove that test works properly
number of hydrogen bonds between thymine/uracil and adenine
2
bronchus
2 divisions of the trachea one into each lung with catilaginous C rings and ciliated epithelial cells
number of hydrogen bonds between cytosine and guanine
3
pyruvate/pyruvic acid
3C compound formed from the double dephosphorylation and dehydrogenation of triose bisphosphate
triose bisphosphate
3C compound formed from the phosphorylation of triose phosphate
triose phosphate
3C compounds formed by the lysis of hexose bisphosphate
Triose phosphate (TP)
3C molecule formed from the hydrogenation of GP by reduced NADP used to make organic molecules
Glycerate 3-phosphate (GP)
3C molecule in Calvin cycle formed from the lysis of the unstable 6C compound formed from the carboxylation of RuBP
creation of a resting potential
3Na+ are actively transported out of axon cytoplasm and 2K+ are actively transported in, Na+ slightly diffuse in more K+ diffuse out due to their conc gradient being higher than their electrochemical gradient, so inside -ve and outside +ve
% of erythrocytes, platelets and leucocytes in blood
45%
How is CO2 transported in blood?
5% carried dissolved in plasma, 10-20% forms carbaminohaemoglobin, 75-85% converted in to carbonic acid them to hydrogen carbonate ions in rbc cytoplasm
% of blood that is blood plasma in blood
55%
Temperature of annealing stage of PCR
55'C
Ribulose bisphosphate (RuBP)
5C Regenerate of the Calvin cycle that fixes carbon from carbon dioxide
hexose bisphosphate
6C unstable compound formed by the double phosphorylation of glucose
Temperature of elongation/synthesis stage of PCR
72'C
width of phospholipid bilayer
7nm
Normal blood glucose concentration
90mg per cm^3
Temperature of denaturation stage of PCR
95'C
Transmission electron microscope (TEM)
A beam of electrons is transmitted through a specimen and focused to produce a 2D image
Scanning electron microscope (SEM)
A beam of electrons sent across the surface of a specimen and detected to produce a 3D image
Phosphodiester bond
A bond between the phosphate group of one nucleotide and the 3rd carbon of another. Formed by a condensation reaction.
Dorsal root ganglion
A bulge in the dorsal root that contains the cell bodoes of the sensory neurones
Capsule slime layer
A capsule of slime that helps prokaryotes move and stick together in colonies
Polysaccharide
A carbohydrate long molecule made by condensation reaction of many sugars
Hydrolysis reaction
A catobolic biological reaction that needs water to break down molecules
Haploid
A cell with half the normal amount of genetic material (n)
Vacuole
A cell's water store. In plants contains a solution of sugars and salts called cell sap. Responsible for a plants turgor
Discontinuous variation
A characteristic that can only appear in specific/discrete values
Discontinuous/discrete variation
A characteristic that can only result in certain values, qualitative
Continuous variation
A characteristic that can take any value in a range, quantitative
Continuous variation
A characteristic that can take any value within a range
Adaptation
A characteristic that increases an organisms chance of survival and reproduction in its environment
Tissue
A collection of differentiated cells that have a specialised function/s
Organ system
A collection of organs working together to carry out a major function in the body
Species evenness
A comparison of the number of individuals of each species living in a community
Diabetes mellitus
A condition where the body cannot effectively respond to insulin produced
Artificial twinning
A cow with desirable traits is treated with hormones and made to super-ovulate, Ova may be fertilised or artificially inseminated in lab by a bull with good traits, after a couple of days whilst all the cells are still totipotent, the embryo is split into several smaller embryos, each separate embryo is grown in the lab for a few days before being implanted into surrogate mothers and embryos develop into clones of each other
Body plans
A cross-sectional representation of an organism showing its fundamental arrangement of tissue layers
Nucleolus
A dark area in the nucleus containing chromatin where ribosomes are made
Phylogenetic/evolutionary tree
A diagram used to represent the evolutionary relationships between orgnisms
Cell plasma membrane
A double layer of phospholipids, glycoproteins and cholesterol, which is selectively permeable
Nuclear envelope
A double membrane surrounding the nucleus
Limiting factor
A factor that prevents the rate of an enzyme's activity not increase by any more
Zygote
A fertilised egg, the source of all cells that an organism develops
Point quadrat
A frame with a horizontal bar with holes for a long pin that can be oushed through and each species it touches can be recorded
Cell wall
A freely permeable structure of the cytoskeleton in some cells.
Regulatory gene
A gene involved in controlling the expression of one or more other genes
Enzyme
A globuar protein with a specific tertiary structure that acts as a catalyst to biological reactions
Insulin
A globular peptide hormone synthesised and released by the Beta cells of the pancreas causing glycogenesis and glucose to fat conversion
Insulin
A globular protein that acts as a hormone to convert glucose into glycogen. Nearly all cells (apart from rbcs) have insulin receptors. Insulin binds to glycoprotein receptor causes a change in the glucose transport protein channels which allows glucose to enter the cell. Insulin also activates enzymes within some cells to convert glucose to glycogen and fat
Cortisol
A glucocortoid that helps regulate metabolism by controlling how the body converts fats, proteins and catbohydrates to energy
Corticosterone
A glucocoticoid that helps regulate blood pressure and cardiovascular function as well as regulate immune response and surpress inflammatory reactions
Growth curve
A graph of number of microorganisms against time
Normal distribution curve
A graphical representation of of continuous variation of frequency against a quantitative trait creating a bell shaped curve
Operon
A group of genes that are under the control of the same regulatory mechanism and are expressed at the same time
Homeobox genes
A group of genes which all contain a homeobox
Lac operon
A group of three structural genes: lacZ, lacY, and lacA involved in the metabolism of lactose in E. coli
Gamete
A haploid sex cell produced by meiosis II
Coarse focusing knob
A knob used to move the specimen stage in large increments to put it in focus
Fine focusing knob
A knob used to move the specimen stage up or down in small increments to put it in focus
Tree beating
A large white cloth is stretched out under a tree, the tree is shaken or beaten to dislodge any insects which fall onto cloth
Laser scanning confocal microscope
A laser of high intensity light illuminates a specimen with fluorescent dye, which is absorbed and re-radiated as light of a longer wavelength and lower energy, focused to produce a magnified image of a single point in a focus plane
Compound light microscope
A light microscope consisting of an eyepiece and objective lenses
Polynucleotide
A long chain of nucleotides joined in condensation reactions, forming phosphodiester bonds between the 3rd carbon of the pentose sugar and a phosphate group
Thermal cycler
A machine that varies the temperature of a sample rapidly over 3 stages for PCR
Temperature coefficient, Q10
A measure of how much the the rate of reaction increases with a 10'C rise in temp
Species biodiversity
A measure of the different types of species in an area
Validity (as applied to a measurement)
A measurement that measures what it is supposed to measure is valid
Vesicle
A membranous sac with proteins destined for exocytosis
Gel electrophoresis
A method of separation of DNA fragments from a mixture based on their length (number of base pairs) and therefore mass
Aldosterone
A mineralocorticoid which helps control blood pressure by maintaining the balance between salt and water concentrationsin the blood and bodily fluids
Dichroic mirror
A mirror which only allows one wavelength of light to be reflected e.g. laser
Antigen
A molecule capable of inducing an immune response on the part of the host organism
Non competitive inhibitor
A molecule with a different structure to the substrate that binds to an allosteric site, inducing a change in the shape of the active site preventing the substrate from fitting complementarily
Reversible inhibitor
A non permanent inhibitor that only affects enzyme action momentarily
Diploid
A normal cell containing two chromosomes of each type (2n)
Homologous chromosomes
A pair of identical matching chromosomes one from each parent
Phase 2 as a stage of a population growth curve
A period of rapid growth where the population multiplies exponentially because the number of breeding individuals increases. No limiting factors act to limit the population exponential growth
Phase 1 as a stage of a population growth curve
A period of slow growth when a small number of individuals that are initially reproduce increasing the total population. Birth rate is higher than death rate so number of organisms increases
Nucleotide
A phosphate, pentose sugar and nitrogenous base known collectively
Potometer
A piece of apparatus used to measure transpiration rate
cholesterol
A polar molecule like a phospholipid, that adds structural support by being in the bilayer and preventing the phospholipids from clumping, crystallising and becoming solid.
Phospholipid
A polar molecule with a hydrophyllic phosphate head and two hydrophillic fatty acid tails ester bonded to the glycerol backbone.
Mass potometer
A potometer that is constantly on a set of scales and the mass recorded over time
Graduated potometer
A potometer that uses a tube and a trapped bubble with a graduated scale from which difference is measured
Secretion
A process by which substances are produced and discharged from a cell, gland or organ for a particular function in the organism or for excretion
First tropic level is always
A producer
operculum
A protective flap that covers the gills
Electrocardiograms (ECG)
A recording of the electrical activity of the heart, detected as tiny electrical differences in the skin
Repressor protein
A regulatory protein that binds to a structural gene and prevents transcription of that gene under certain conditions
Isolated enzymes
A relatively pure preparations of an enzyme which has been extracted and purified from a biological source.
Clinostat
A rotating motor that hilds a plant used to investigate geotropism
Vaccine
A sample of a pathogen that has been attenuated but triggers an active immune response resulting in immunity
Stage graticule
A scale placed on the specimen stage to calibrate the eyepiece graticule
Food web
A schematic often pictorial representation of the interactions between organisms in a given ecosystem with arrows showing the transfer of energy/biomass from one organism to another
Homeobox
A section of DNA 180 pairs long coding for a part of the protein 60 amino acids long that is highly conserved in animals, plants and fungi
Metabolic pathways
A series of biological reactions to give a necessary product
Monosaccharides
A single carbon ring sugar/simple sugar
Nitrogenous base
A single or double carbon ring attached to the 1st carbon of the pentose sugar.
Allosteric site
A site different to the active site to which non competitive inhibitors bind to
Plasmid
A small circular strand of DNA
Pitfall traps
A small hole in ground with roof to catch small crawling invertibrates. Hole must be deep enough so it doesnt crawl out amd roo to prevent rainwater from drowning insects. Left overnight to also nocturnal insects
Microsatellites/ short tandem repeats (STRs)
A smaller region of just 2-4 base pairs repeated only 5-15 times.
Frame quadrat
A square frame divided into a grid with smaller squares of equal area. Species number or percentage coverage can be measured
Chi-squared test
A statistical test to measure the size of difference between the observed results and expected results
Potency
A stem cell's ability to differentiate into different cell types
seed bank
A store of samples of seeds from both wild type and domesticated varieties
Homologous structures.
A structure that appears superficially different in different organisms but has the same underlying structure
Substrate
A substance that interacts with an enzyme to produce product/s
The specific/active/acquired immune system
A subsystem of the overall immune system that is composed of highly specialized, systemic cells and processes that eliminate or prevent pathogen growth.
DNA profiling
A technique to assist identification of individuals or familial relationships
Capture-mark-release-capture
A technique to estimate population size. Animals are caught, marked then released and recaptured based on the number recaptured that are marked the population size can be estimated
Circulatory system
A transport system used to transport gases, nutrients, waste products and hormones around the body
Codon
A triplet of bases on mRNA coding for one amino acid
Pooter
A two tubed jar used to catch insects, by sucking on mouthpiece you suck insect into holding chamber via inlet tube
Lysosome
A vesicle containing proteins that break down old organelles
Artefact
A visible structural detail caused by processing the specimen, which is not a feature of the specimen
Flagellum
A whip like tail extension protruding from cells responsible for cell mobility and a chemical sensory organelle
ATP + H20 =
ADP + Pi + energy (30.6kJmol^-1)
substrate level phosphorylation of Kreb's Cycle
ADP is phosphorylated by the removal of a phosphate group from the 4C compound
2 Types of limiting factors
Abiotic limiting factors and biotic limiting factors
Carotenoids
Accessory pigments responsible for yellow/orange colour in plant leaves
Physiological adaptations
Adaptations of internal processes of an organism
Connective tissue
Adapted either to hold other tissues together or as a transport medium
Vascular tissue
Adapted for transport of water and nutrients
Muscle tissue
Adapted to contract
Squamous Epithelial tissue
Adapted to cover body surfaces, internal and external, very thin flat only one cell thick reduces diffusion distance
Epidermis tissue
Adapted to cover plant surfaces, thin single layer covered by waxy, hydrophobic cuticle to reduce transpiration
Nervous tissue
Adapted to support the transmission of electrical impulses
Inoculation
Adding microorganisms to a culture medium using aseptic techniques
Acylation during histone modification
Addition of acetyl groups to histone making them less -ve so they coil DNA less tightly
Methylation during histone modification
Addition of methyl groups to histones making them less +ve so they coil DNA more tightly
Types of post-translational control
Addition of non-protein groups (carbohydrate, lipids, phosphates), modifying amino acids and the formation of bonds (disulfide bonds), folding or shortening of proteins, modification by cAMP
Phosphorylation during histone modification
Addition of phosphate groups to histones making them less -ve so they coil DNA less tightly
Purines
Adenine and Guanine. Double ring carbon, nitrogenous bases
3 main groups for the reasons for maintaining biodiversity
Aesthetic, economic, ecological
Growth hormones
Affect the growth of bones and muscles of mammals in humans called HGH
Thyroxine
Affects metabolic rate released by the thyroid gland
Melatonin
Affects reproduction and daily cycles eg circadian rhythm
Enzyme-product complex
After the substrate reacts the products form this before being released
Ecological reasons for maintaining biodiversity
All organisms interdependent on others can cause large-scale damage eg keystone species and pollinators,
Genome of eukaryotes
All the DNA in the nucleus and mitochondria combined
motor unit
All the fibres supplied by a single motor neurone - the fibres act as a single unit
Genome of an organism
All the genetic material that the organism contains
Solvent
Allows water to act as a transport medium causing dissociation. Removes metabolic wastes like urea and ammonia
Types of cells in the islets of Langerhans
Alpha cells amd beta cells
Snowdonia National Park plants present
Alpine plants: Snowdon Lily, Oak and elm forests in lower altitude areas
Loci of micro- and minisatellites
Always appear in the same positions on the chromosomes the number of repeats of each varies between individuals because different lengths of repeats are inherited from both parents
Residual volume
Amount of air remaining in the lungs after a forced exhalation
3 important types of digestive enzymes produced by pancreas
Amylases, proteases, lipases
ADP (adenisine diphosphate)
An ATP molecule that has had one of its inorganic phosphate groups removed by hydrolysis releasing energy. Can be phosphorylated back to ATP
Tachycardia
An abnormally high heart rate, beats evenly spaced, rate > 100bpm
Bradycardia
An abnormally low heart rate < 60bpm, beats evenly spaced, may need a pacemaker in extreme cases
Condensation reaction
An anabolic biological reaction that produces a product and water
Active site
An area within the tertiary structure of an enzyme having a complementary shape to a specific shape of a substrate
Spliceosome
An enzyme complex that loops introns cuts them out of pre-mRNA then sticks the exons together
Denatured
An enzyme with a disrupted tertiary structure, which affects the shape of its active site deactivating it permanently
Founder effect
An extreme example of genetic drift where an isolated part of a population forms a new population which has a different allele frequency to the original population but its is constant with the founder population
Stage 1 of a predator-prey relationship graph
An increase in the prey population provides more food for the predators, allowing more of them to survive and reproduce, which causes a slightly delayed increase in the predator population
Irriversible inhibitor
An inhibitor that permanently deactivates an enzyme
manual sphygmomanometer
An instrument for measuring blood pressure in the arteries, especially one consisting of a pressure gauge and a nylon or rubber cuff that wraps around the upper arm and inflates to constrict the arteries.
Validity (as applied to a investigation)
An investigative procedure that is suitable to answer the question being asked
Saprophytic feeder
An organism that acquires nutrients through absorption and secretion of extra cellular enzymes
Transgenic/genetically modified organisms (GMO)
An organism that has had its genome manipulated by genetic engineering
Heterotrophic feeder
An organism that ingests part of or whole other organisms
Autotrophic feeder
An organism that make their own food
Autotroph/Producer
An organisms that produces complex organic molecules from simple substrates present in its surroundings, generally using light energy from the Sun or inorganic chemical
Uses of DNA sequencing
Analysing the human genome, analysing the genomes of pathogens, identifying species (DNA barcoding), phylogeny
Sensor used to measure wind speed
Anemometer
6 Kingdom classification system
Animalia, plantae, proticista, fungi, bacteria, archae
5 Kingdoms classification system
Animalia, plantae, proticista, fungi, prokaryotae
Triploblastic animals
Animals that have three primary tissue layers
Diploblastic animals
Animals that have two primary tissue layers
Antarctica control of human activities
Antarctic Treaty formed, nations cooperate there for science, conservation of plants and animals in protected areas, encourage ecotourism and limit effects of tourism
Agglutinins
Antibodies act as these causing pathogens carrying antigen-antibody complexes to clump together
Purkyne fibres
Any of the specialized cardiac muscle fibers, part of the impulse-conducting network of the heart, that rapidly transmit impulses from the atrioventricular node to the ventricles.
Pathogens
Any organism that causes a disease and can include bacteria, viruses, fungi and protoctista
The Galapagos Islands brief description
Archipelago in Pacific Ocean famous for Darwin's finches/place where he developed his theory of evolution by natural selection
Hox genes
Are one group of homeobox genes that are only present in animals and are responsible for the correct positioning of the body parts.
Peat bogs key issues
Areas cleared for agriculture. Aforestation dries out bogs, erosion and flooding as a result. Peat bogs are CO2 srtores. Peat extracted and dried for use as a fuel and for cheap composts
Methods of artificial cloning in vertebrates
Artificial twinning, Somatic cell nuclear transfer (SCNT)
Arguments for animal cloning
Artificial twinning: enables high-yield farm animals to produce many more offspring than normal sexual reproduction, the success of a male animal at passing on desirable genes can be determined; SCNT: Gm animals can be replicated, specific animals can be cloned, has potential to enable rare, endangered or even extinct animals to be reproduced
Stage 2 of an intraspecific competition graph
As a result of the increased population resources become a limiting factor as more individuals have to share the available resources and the population size decreases
Bohr effect
As the pCO2 increases the affinity of Hb to O2 is less strong
Annealing as a stage of PCR
At a temperature of 55'C the primers anneal(bind by hydrogen bonds) to the complementary region
Synthesis as a stage of PCR
At a temperature of 72'C -the optimum of the Taq DNA polymerase it starts at the primers and synthesises a double strand
Denaturation as a stage of PCR
At a temperature of 95'C the hydrogen bonds between base pairs in the sample DNA strand are broken and single strands are left
effect of CO2 of pO2
At higher pCO2 the % saturation of Hb with O2 is lower at the same pO2 meaning Hb has a lower affinity to oxygen
Cohesion
Attraction between molecules causes flowing in xylem and surface tension
Examples of genuses of nitrogen fixing bacteria
Azotobacteria (free living soil bacterium), Rhizobium (in symbiotic mutualistic relationship with leguminous plants living in root nodules)
Genus of free-living soil nitrogen-fixing bacteria
Azotobacterium
Lag phase explanation
Bacteria are adapting to their new environment, growing, synthesising necessary enzymes
Vector formation in genetic engineering
Bacterial plasmids used have marker genes for antibiotic resistance so unsuccessfully transformed cells are killed off and for fluorescent proteins. Plasmids cut with same restriction endonucleases and gene sticks to complementary sticky ends on plasmid. DNA ligase used to stick backbone together
reproductive barriers
Barriers that prevent successful interbreeding within a population before and after fertilisation has occurred
Behavioural responses as a form of thermoregulation in ectotherms (and endotherms) to increase body temperature
Basking in sunlight by orientating bodies and extending areas to maximise surface area, conduction by pressing bodies to warm ground, exothermic metabolic reactions, hibernation in coldest weather
Types of bioprocesses/fermentation
Batch fermentation and continuous fermentation
Density
Because ice is less dense than water (because the crystalline structure means water molecules are further apart than if they were liquid) means it floats and so bodies freeze from the top and have an insulating layer.
Learned behaviour
Behavioural adaptations learned from experience or from observing other individuals
Methods of immobilisation of enzymes
Binding to an inert, insoluble, inorganic carrier by adsorption or by ionic or covalent bonds, entrapment in a matrix, encapsulation in alginate polymer balls
How is biomass measured?
Biomass is measured as dry mass as water content is variable so a sample of an organism is put in an oven 80'C until its mass is constant, however a sample may not be representative of a whole population
Types of factors affecting ecosystems
Biotic and abiotic factors
Metaphase I
Bivalents assemble along metaphase plate, INDEPENDENT ASSORTMENT means randomnly maternal and paternal chromosomes face poles of cells
Examples of a positive feedback system
Blood clotting cascade, change in membrane potential when increases above threshold voltage, oxytocin release and contractions during childbirth
Closed circulatory system
Blood is enclosed in blood vessels and doesn't come into contact with other body fluids
Pinocytosis
Bulk transport of liquids into cells
Endocytosis
Bulk transport of material into cells
Exocytosis
Bulk transport of material out a cell through vesicles
Phagocytosis
Bulk transport of solids into cells
Ways of identifying bacteria pathogens
By their basic shape, by their cell walls (gram egg or pos)
respiratory quotient
CO2 produced/O2 consumed
Light-independent stage of photosynthesis
Calvin cycle
Inbreeding
Can be a result of excessive selective breeding where genetic variation is very low. It increases the risk of genetic diseases that affect the whole population
Advantages of using immobilised enzymes
Can be reused - which is cheaper, easily separated from reactants and products reducing downstream processing and separation costs, more reliable - higher degree of control, greater temperature tolerance as less easily denatured so work at a wider optimum range, ease of manipulation to fit particular process
Methodology of capture-mark-release-recapture technique of measuring animal abundance in an ecosystem
Capture as many individuals as possible in a sample area, mark or tag each individual, release the marked individuals into the sample area and allow them to redistribute themselves throughout the habitat, recapture as many individuals as possible in the original sample area, record the number of marked and unmarked individuals present in the sample, release all the individuals back in to their habitat, use the Lincoln index to estimate the population size
Cytokines
Cell signalling molecules released by phagocytes that have engulfed a pathogen informing them that the body is under attack and stimulating them to move to the site of infection or inflammation. Can also increase body temp and stimulate specific immune system
Forming structures by mitosis and apoptosis
Cells proliferate by mitosis, then unwanted structures are removed by apoptosis to shape structures, can also be added by further mitosis
companion cells
Cells that are linked to sieve tube cells by many plasmodesmata because they have lost their normal cell functions
Differeniated cells
Cells that are specialised to carry out very specific functions
Prokaryotes
Cells that do not have a nucleus and membrane bound organelles
Eukaryotes
Cells that have a true nucleus and membrane bound organelles
Anaphase II
Centromere division, individual chromatids pulled by spindle fibres to opposite cell poles
Copicing as a method of sustainable small-scale timber production
Certain types of trees can be cut at the base and the timber harvested, they regrow from the base and can be continually harvested in this way rotationally
Streptobacilli
Chain of bacilli
Streptococci
Chain of cocci
Nasal cavity
Chamber into which air is breathed in covered in many hairs and rich blood supply to catch dust and pathogens and warm up air
Positive feedback system
Change detected by sensory receptors and effectors are stimulated to reinforce the that change and increase the response
Factors affecting the expression of regulatory genes
Changes in internal or external environment, drugs
Dihybrid inheritance
Characteristics controlled by 2 genes
Monogenetic/monohybrid inheritance
Characteristics controlled by only one gene
G2 checkpoint
Checks for: cell size, DNA replication, DNA damage.
G1 checkpoint
Checks for: cell size, nutrients, growth factors, DNA damage
Hormones
Chemical messengers secreted by the endocrine system and bind to receptors in target cells to initiate a change
Chemoreceptors controlling heart rate
Chemical receptors that detect chemical changes such as pH because when CO2 levels are high there is a lower pH due to more carbonic acid
Opsonins
Chemicals that bind to pathogens and tag them so that they can be more easily recognised by phagocytes
Examples of a characteristic in plants that is a result of environmental variation and genetic variation
Chlorosis, etoliation
Anaphase I
Chromosomes are pulled to different poles of the cell by centrioles' spindle fibres
sphincters
Circular muscles that encircle and, by contracting, constrict spiracles in insects
cofactor for amylase
Cl-
Main soil types as edaphic factors affecting ecosystems
Clay-fine particles, easily waterlogged, forms clumps when wet; loamy-different sized particles, retains water, doesn't become waterlogged; sandy-coarse, well-separated particles, free draining, doesn't retain water well, easily eroded
Staphylococci
Cluster of cocci
Exons
Coding regions of mRNA
Exons
Coding regions of pre-mRNA
Organ
Collection of tissues that are adapted to perform a particular function in an organism
Photosystem
Collectively of the light harvesting system and reaction centre
Colostrum
Colostrum is a form of milk produced by the mammary glands of mammals in late pregnancy. It contains antibodies from mother's blood
Vibrio
Comma shaped bacteria
Spirometer
Commonly used to measure different aspects of the lung volume or to investigate breathing patterns
Ecosystem
Community of living organisms in conjunction with the physical components of the environment (air, water) that interact with each other in a defined area
Examples of biotic factors
Competition for resources between organisms in a population or between different populations for includes predation) , territory, mates
Natural selection
Competition in a species, variation and environmental changes mean the best adapted organism is more likely to survive and pass on characteristics
Conditions for evolution
Competition, variation, heredity, selection mechanism or pressure
White matter
Conatains many myelinated and unmyelinated neurones amd not many cell bodies
Ex situ conservation
Conservation out of the natural habitat and involves removal of organisms from their natural habitat
In situ conservation
Conservation within the natural habitat
Tropic levels after the first tropic level are always
Consumers
Secondary consumers
Consumers that eat primary consumers
Primary consumers
Consumers that eats a producer
Identification key
Contain images and discernable characteristics to help identify organisms
Nuclues
Contains all genetic material in a cell in chromosomes
Grey matter
Contains many cell bodies and not many axons
Microfilaments
Contractile fibres made of actin. Responsible for cell movement.
Checkpoints
Control mechanisms of the cell cycle, that monitor and verify accurate phase completion. Only after successfully passing a checkpoint a cell can enter the next phase.
Stomatal control mechanism
Controlled by ABA (abscissic acid). When water in low supply abscissic acid produced that binds to receptors in guards cells that increases their water potential and they lose water and close stomata
Type 1 diabetes treatment (insulin dependent)
Controlled by regular injections of insulin
Oestrogen
Controls ovulation and female secondary sexual characteristics
Testosterone
Controls sperm production and male secondary sexual characteristics
Confocal pinhole
Controls the amount of re-radiated light arriving at the detector
Illumination pinhole
Controls the amount of the laser's light being emitted
Glucagon
Converts glycogen back to glucose in the liver
Spirochaete
Corkscrew shaped bacteria
Transformation methods in genetic engineering
Culture bacteria in calcium-rich solution so recombinant plasmids can pass through permeable membranes. Electroporation where a small current passed over cell to increase membrane permeability. Electrofusion for fusing two animal cells
Stages of Light-dependent stage of photosynthesis
Cyclic phosphorylation, non-cyclic phosphorylation, photolysis
Pyrimidines
Cytosine, Thymine and Uracil. Single ring carbon, nitrogenous bases
Prophase I
DNA condenses into chromosomes, nuclea membrane dissolves, spindle fibres start to be produced by centrioles, homologous pairs of chromosomes pair up, CROSSING OVER OCCURS
Prophase II
DNA condenses into chromosomes, nuclear membrane dissolves, spindle fibres start to be produced by centrioles,
Main stages of gel electrophoresis
DNA fragment mixture put in wells in agarose gel strips with buffer at origin at cathode. Electrical current switched on and DNA fragments move to anode due to -ve phosphate groups. Distance moved is inversely proportional to their length
Separation as a main stage of DNA profiling
DNA fragments are separated by electrophoresis by applying a electric current through the fragments on a gel mesh, then immersed in alkali solution to separate the strands into single strands. Single strands then transferred to a membrane by Southern blotting
Main stages of Southern blotting
DNA fragments denatured in alkaline solution to give single strands. These strands are transferred to nitrocellulose paper or nylon membrane by placing a stack of absorbent paper on the gel which draws up the solution with the DNA in their correct positions. DNA single strands unable to pass through membrane so stick to it. Fixed in place by heating of UV light
Extraction of DNA as a main stage of DNA profiling
DNA is extracted from a tissue sample. If too little DNA is contained in the sample PCR can be used to reproduce the DNA
S phase (Synthesis phase)
DNA is replicated in the nucleus.
Substances added to a thermal cycler for PCR
DNA sample to be amplified, excess of bases, excess of primer complementary to ends of sample, heat-resistant DNA polymerase
Method of DNA sequencing
DNA to be sequenced is mixed with primers, DNA polymerase, excess of normal nucleotides. Mixture placed in a thermal cycler. At 96'C DNA separates into single strands, at 50'C primers anneal to DNA strands, at 60'C DNA polymerase starts to build up new DNA strands by adding complementary bases to template. Each time a terminator base is added DNA polymerase stops. Cycle repeated many times. Capillary sequencing used to separate and identify final base of each strand with a terminator. Computer can then determine the order of sequences of the original DNA
Histone modification
DNA which is -vely charged is attracted to +vely charged histones during condensation, acylation or phosphorylation reduces +ve charge on histones causing DNA to coil less tightly, methylation does the opposite so DNA cannot be transcribed
Modes of action of pathogens
Damaging host tissues directly, producing toxins that damage host cells
Physiological responses as a form of thermoregulation in ectotherms to increase body temperature
Darker colourings, alter their heart rate to increase/decrease metabolic rate
Abiotic stresses affecting plants
Day length/light intensity, temperature, water availability, wind.
Extinct taxa
Dead species
Terai region key issues
Deforestation causes loss of habitat and poverty as locals rely on forest for income. Flooding common and devastates locals.
Types of translational control
Degradation of mRNA, inhibition of mRNA, activation of initiation factors, protein kinases
Steps of PCR
Denaturation/separation of sample DNA, annealing of primers, elongation/synthesis of DNA
types of limiting factors
Density-dependent factors and density-independent factors
endotherms
Depend on metabolic processes to warn up and maintain a very stable core body temperature regardless of environmental temperature
Divergent evolution
Describes how species have evolved from a common ancestor, with a different set of adaptive features.
Sequence of steps in genetic engineering
Desired gene is isolated by restriction endonucleases with sticky ends. Plasmid from a bacterial cell is removed and cut with the same restriction endonucleases. The desired gene and plsmid have complementary sticky ends so combine forming a recombinant plasmid. DNA ligase used to fuse the DNA backbone. Recombinant plasmid introduced into new host cells, bacteria multiply in fermenter, downstream processing, pure desired product
Receptor
Detect changes in internal or external environment
Sustainable development
Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
Blood glucose concentration can increase by
Diet (eating carbohydrates), glycogenolysis, gluconeogenesis
Environmental variation
Differences in individuals of a species due to their environment
Genetic variation
Differences in the genetics material an organism inherits from its parents
Edaphic factors as abiotic factors affecting ecosystems
Different soils have different particle sizes which has an effect on the organisms that can live there
Alleles
Different versions of the same gene
Causes of genetic biodiversity
Different versions of the same gene called alleles and account for genetic biodiversity
Direct contact
Direct contact of a healthy plant with any part of a diseased plant
Liver cirrhosis
Disease where normal liver tissue is reolaced by fibrous scar tissue. Causes can be Hep C, genetic or excessive alco hol intoxication
Allopatric speciation
Divergent speciation due to geographical factors
Order of taxonomical hierarchy
Domain, kingdom, phylum, class, order, family, genus, species
Leaf abscission mechanism
Due to less light intensity leaf produces less auxins and plant produces more ethene. This switches on genes that code for cellulases that destroy cells in abscission zone and leaf falls
Degenerate code
Each amino acid has more than one coding triplet
Why is the genetic code described as non-overlapping?
Each codon is read seperately always as the 3 base pairs
Trophic levels
Each stage in a food web where biomass/energy is transferred from one organism to another
Advantages of using isolated extracellular enzymes rather than intracellular isolated enzymes
Easier to isolate - they are secreted, and each microorganisms produced relatively few extracellular enzymes, more robust - extracellular conditions not as constant as intracellular conditions
Environmentally sensitive ecosystems
Ecosystems that are less resistant to changes in them/more fragile
Types of glands
Endocrine and exocrine
The Lake District National Park brief description
England's largest National Park, woodlands, lakes, range of habitats
Biocides
Enzyme inhibitors used to kill organisms by inhibition. Used commonly in agriculture
Ribulose biphosphate carboxylase (RuBiCO)
Enzyme responsible for the fixation of carbon dioxide to RuBP in Calvin Cycle (incredibly inefficient)
Protein kinases
Enzymes that catalyse the addition of phosphate groups to proteins which changes their tertiary structure which activates so they act as regulators of cell activity, protein kinases are activated by cAMP
Immobilised enzymes
Enzymes that have been trapped in a matrix or bound to a surface to make a process more efficient because it reduces downstream processing
Extra cellular enzymes
Enzymes that perform their role outside the cell that made them
Lincoln index used to estimate population size
Estimated population size = n of sample 1 x n of sample 2 / n of recaptured marked individuals
3 Domains
Eukarya, Eubacteria, archae
Latent heat of vaporisation ( the amount of heat needed to turn a substance into a gas)
Evaporation methods are efficient cooling mechanisms helping maintain a constant body temp.
environmental causes of temperature decrease in organisms
Evaporation of water, conduction, convection and radiation to environment
Pancreaic acini
Exocrine tissue of pancreas, small berry-like clusters that produce and secrete digestive enzymes
gills
Extensions of the body containing thin-walled blood vessels that allow for easy absorption of oxygen from the outside surface
Main stages of producing a DNA profile
Extraction of DNA, digestion of sample, separation of DNA, hybridisation, development
density-dependent factors
Factors dependent on population size inluding competition, predation, parasitism, communicable diseases
Selection pressures
Factors that affect the organisms chances of survival or reproductive success
limiting factors (genetics)
Factors which limit or decrease the size of a population
Masai Mara key issues in area
Farming: Masai Mara tribes only allowed to let cattle graze on outskirts of nature reserve, trees removed by tribes for fuel increasing soil erosion, tribes have reliance on fertilisers due to overuse of cropsfields, ecotourism ensures sustainable development and conservation of area
Masai Mara balancing human needs and conservation
Fenced areas to prevent elephants and wildebeest from damaging crops however there may be interspecific competition between livestock and native species for food, legal hunting used to as means of income and culling of excess animals. As Masai populations increase more crops and livestock which affect wildlife
Rough endoplasmic reticulum
Folded membranes joined to the nuclear membrane made of cisternae. Has ribosomes on its surface, site of protein synthesis
Smooth endoplasmic reticulum
Folded membranes joined to the nuclear membrane made of cisternae. Site of carbohydrate and lipid production
Cristae
Folds of the inner membrane of mitochondria with respiratory enzymes
Uses and applications of DNA profiling
Forensics where only a small sample of DNA is obtained, proving paternity, indentification of individuals who at risk of developing particular diseases
Terai region conservation and research
Forest management: National laws, local people employed by state to manage forests, work with FSC by increasing sustainability of deforestation and increasing price of timber products. Agriculture: sustainable, not in deforested areas, on hill regions, better irrigation, nitrogen fixing legumes grown and manure used instead of fertilisers
Okazaki fragments
Fragment made by DNA polymerase, going from the replication fork
Methods of artificial cloning in invertebrates
Fragmentation of starfish or liquidation of sponges will create new individuals that regenerate from most fragments
Nuecleoid region
Free chromosomal 'naked' DNA not bound by a membranous nucleus
Types of isolated enzymes
Free isolated enzymes and immobilised isolated enzymes
Transpiration
Fthe loss of water vapour from plants from their leaves and stems
C ->
G
The three stages of interphase
G1, S, G2
Medical production of insulin
Generically modified bacteriathat produce pure human insulin
Linked genes
Genes with loci on the same chromosome
Cause of continuous variation
Genetic and environmental
The importance of genetic biodiversity
Genetic biodiversity is important because the greater the genetic biodiversity of a species the more able the species is to adapt to changes in their environment, hence less likely to be extinct as there is a greater chance that some individuals will have an advantageous characteristic
Clones
Genetically identical organisms (identical to parent and to other cloned offspring)
Monozygotic twins
Genetically identical twins produced when the early embryo splits into two separately developing embryos
Bacterial vector transformation as an example of genetic engineering in plants
Genetically modified bacteria that cause tumours in plants transfer genes in micropropagation forming a callus of GM plant cells
Methods of genetic engineering in plants
Genetically modified bacteria used as a vector, electrofusion
Factors causing variation
Genetics, environment
Intermediate fibres
Give a cell mechanical strength
Antarctica problems caused by human activities
Global warming melts ice sheets, hunting of marine mammals, over-fishing, tourism: water pollution, soil contamination, disruption of animals' mating and feeding habits
Glucagon increases blood glucose concentration by
Glycogenolysis, reduces the amount of glucose absorbed by liver cells, increases gluconeogenesis
Gonadotropins
Glycoprotein, polypeptide hormone in vertebrates, in humans: follicle stimulating hormone (FSH) and human chorionic gonadotropin (hCG)
Reasons why agriculture is the main reason why deflected succession occurs
Grazing and trampling of vegetation by domesticated animals - results in large areas remaining as grassland, removal of existing vegetation to plant crops - crop becomes plagioclimax, burning as a means of forest clearance increasing biodiversity due to secondary ecological succession recolonisation
Cilia
Hair-like extensions, stationary cilia are used as chemical sensors, mobile cilia beat in rhythmically to move fluids
Semiconservative replication
Half of the original DNA is conserved in the new strand that is formed ensuring a direct copy
When sampling animals
Handle them carefully for as little time as possible and release where they were found
decomposers
Harness chemical energy in organic ,molecules from consumers and producers in the exothermic reaction of respiration
consumers
Harness chemical energy in organic, molecules from consumers in the exothermic reaction of respiration
T helper cells
Have CD4 receptors on their cell-surface membrane, which bind to the surface antigens on APCs. They produce interleukins - cytokines that stimulate the the activity of B cells
Control of heart rate
Heart rate is involuntary and controlled by medulla oblongata in the autonomic nervous system
Common symptoms of diabetes mellitus
High blood glucose concentration, glucose present in urine, excessive frequency of urination (polyuria), excessive thirst (polydipsia), constant hunger, weight loss, blurred vision, tiredness
Snowdonia National Park brief description
High mountain range in N Wales, lakes, rivers, heath, woodland
Hyperglycaemia
Higher than normal blood sugar level/glucose concentration
Magnification
How many times larger the image is than the actual size of the object being viewed
Non-steroid hormones
Hydrophillic so cannot pass through membranes bind to receptors on the cell surface membrane of target cells
alleles of the polymorphic immunoglobulin gene in humans
IA, IB, IO
Development as a main stage of DNA profiling
If radioactive DNA probes used X-ray images are taken. If fluorescent DNA probes used membrane placed under UV light and the fluorescent tags glow. Both give a unique pattern of bars called a DNA profile
Reasons why the abundance of a species may fluctuate
Immigration and births will increase numbers of individuals, emigration and deaths will decrease the number of individuals
Reduced NADP/NADPH/NADPH2
Important coenzyme involved in the light independent stage of photosynthesis in the synthesis of complex organic molecules
tracheoles
In insects, narrow tubes branching from trachea and making direct contact with cells to facilitate gas exchange
Chloroplast
In plant cell, the organelle responsible for photosynthesis
Main stages of micropropgation/tissue culture
In sterile conditions a tissue sample from a shoot tip or axial bud, sample is sterilised in bleach, ethanol or sodium dichloroisocyanurate, explant put in sterile culture medium of auxins and cytokinins stimulating mitosis, producing a callus, callus divided into clumps cultured on medium with different composition which stimulates plantlets, plantlets potted out then planted out to grow and produce a crop
Denitrification
In waterlogged soil in the absence of oxygen, nitrifying bacteria cannot fix convert nitrogen so they use nitrates as a source of energy
Type 1 diabetes
Inability to produce glucose
Glucocorticoids
Include cortisol that helps regulate metabolism by controlling how the body converts fats, proteins and catbohydrates to energy, helps regulate blood pressure and cardiovascular function as well as regulate immune response and surpress inflammatory reactions
Common factors of exchange surfaces
Increased surface area, thin layers, good blood supply, ventilation to maintain diffusion gradientr
Adrenaline
Increases heart rate by sending blood quickly to the muscles and brain, rapidly raises blood glucose concentration levels by converting glycogen to glucose in the liver
Insulin lowers blood glucose concentration by
Increasing rate of aborption of glucose by skeletal muscle cells, increasing respiration rate of cells, increases rate of glycogenesis, increases the rate of glucose to fat conversion, inhibits the release of glucagon from alpha cells of the islets of Langarhans
Causes of genetic variation
Independent assortment, crossing over events, random fertilisation
Soil contamination
Infected plants can leave pathogens or reproductive spores of protoctists or fungi in the soil
Communicable diseases
Infectious diseases spread from organism to organism caused by organisms known as pathogens
Mesosome
Infolding of a prokaryote's internal membrane. Site of early respiration processes
Inhibition of mRNA
Inhibitory proteins can bind to mRNA which prevents it from binding ribosomes so prevents translation
Activation of initiation factors
Initiation factors are substances that aid binding of mRNA to ribosomes so when activate increase rate of translation
Batch fermentation
Inoculated medium is allowed to go through all stages of its growth curve, used to make secondary metabolites
Activators
Inorganic groups that are permanently bound to the enzyme like a prosthetic group
Inspiration
Intake of breath
secondary structureof proteins
Interactions between polypeptide chains such as alpha helices and beta pleated sheets due to hydrogen bonding
Capillarity
Intermolecular forces causes water to rise up in tubes of small diameters, which is helpful in plant xylem.
Stroma
Internal fluid in a chloroplast
Thylakoid
Internal membranes form flattened sacs
Anatomical adaptations
Internal or external physical adaptation features
Glycoprotein
Intrinsic proteins, with a carbohydrate chain attached of varying shapes and lengths. Act as receptors for chemical signals and aid cell adhesion.
Types of postzygotic sympatric speciation
Inviable zygote, hybrid sterility
Reason why DNA Polymerase is not denatured in the denaturation stage of PCR
It is extracted from extremophile bacteria that have a heat-resistant type of DNA polymerase so at 95'C it is not denatured
Objective lens
It magnifies the specimen being viewed
Disadvantages of propagation from cuttings
Lack of genetic diversity/variation if a new disease or pest appears or if climate change occurs
Stages of a growth curve (in order)
Lag phase, log/exponential phase, stationary phase, death/decline phase
Sweep net
Large nets that are used in a sweeping motion to catch insects in areas of long grass
Population bottlenecks
Large reductions in population size which lasts for at least one generation. Gene pool and genetic diversity is greatly reduced
Islets of Langerhans
Large sherical clusters of endocrine tissue of pancreas, responsible for producing insulin and glucagon, secreting them directly into bloodstream
Advantages of using isolated intracellular enzymes rather than isolated extracellular enzymes
Larger range of intracellular enzymes, so more useful in specific reaction, specificity outweighs expensive isolation process
Protection layer
Layer before the seperation zone in leaf petiole covered by suberin to waterproof vascular vessels and prevent pathogens from entering
sexual selection
Leads to an increase in allele frequency of alleles which code for characteristics that improve mating success
Plant response to decreased day light/light intensity
Leaf abscission
Stage 3 of an intraspecific competition graph
Less competition due to a smaller number of individuals means that resources are in plentiful supply so individuals survive and reproduce increasing the population size
Advantages of using isolated enzymes over whole (micro)organisms
Less wasteful - don't need growing substrates, more efficient - can work at higher substrate concs, purer product - no side reactions/products from other enzymes, maximised efficiency - can be given ideal conditions which are different to whole organism's, less downstream processing - pure product formed
Non-cyclic phospholrylation (Z scheme)
Light absorbed by PSII, 2 e- released, accepted by e- acceptor, go along e.t.c. making ATP. 2 e- absorbed by deficient PSI. Light ansorbed by PSI, 2 e- released to e- acceptor, pass along e.t.c., along with 2 H+ convert NADP to reduced NADP
Unilateral light
Light coming from only one side
The stages of photosynthesis
Light dependent stage, light independent stage
Factors affecting transpiration
Light intensity, Relative humidity, Temperature, Air movement, Soil-water availibility
The limiting factors of photosynthesis:
Light intensity, temperature, carbon dioxide concentration
Examples of abiotic factors
Light, temperature, water availability, oxygen availability, edaphic (soil) factors
Phytochrome
Light-sensitive pigments responsible for photoperiodism. Has two forms: Pr and Pfr each absorbing different types of light
density-independent factors
Limiting factors that affect populations of all sizes in the same way including climate change, natural disasters, seasonal change, human change (deforestation)
Problems caused by interbreeding
Limiting the gene pool reduces genetic diversity so reduces the chance of evolution, lack of genetic diversity may cause a higher frequency of genetic disorders (both revessive amd dominant) as more are carriers meaning a an organism becomes less biological fit
Steroid hormones
Lipid soluble so can pass through phospholipid bilayer and attach to receptors in the cytoplasm or nucleus of target cells
Glycolipid
Lipids with attached carbohydrate chains. Called cell markers or antigens, help in identification in immune system as foreign or non foreign cell.
Biotic factors
Living factors caused by the interactions between organisms that are living or have once lived
Extant taxa
Living species
Demes
Local interbreeding populations
Gram positive bacteria
Look purple blue under a light microscope eg MRSA
Gram negative bacteria
Look red pink under a light microscope eg E. coli
reasons for uncertainty in the details of many plant responses
Low concentrations of plant hormones so isolation and measuring their concentration change is difficult, multiple interactions between different chemical control systems
Hypoglycaemia
Lower than normal blood sugar level/glucose concentration
Ribosomes
Made in nucleolus they read mRNA and produce polypeptide chains of bonded amino acids
Phospholipid bilayer
Made of a double layer of phospholipids, where the hydrophobic tails attract each other, creating a hydrophyllic surface. This contains an internal environment and is flexible but strong
Centriole
Made of microtubules they assemble and organise the cytoskeleton
Eyepiece lens
Magnifies the magnified image produced by the objective lens
The Galapagos Islands animals present
Mainly reptiles: marine iguana, lizards, Galapagos giant tortoise
Peat bogs conservation and research
Maintain and control water levels by: controlled grazing of livestock, removal of seedling trees, ditch blocking to raise water levels, preventing flooding by researching, reducing the drying and extraction of peat
Homeostasis
Maintainance of a dynamic equilibrium to keep a constant internal environment by small changes over a narrow range of conditions
Accessory pigment
Make up the antennae complex
Why is the genetic code described as degenerate?
Many codons code for one amino acid
Line transect
Marking a line along the ground between points and taking samples at specific points
Vitalograph
Measures the forced exploratory volume in 1 second
Peak flow meter
Measures the rate at which air can be expelled from the lungs
Continuous fermentation
Medium inoculated and allowed to grow until log phase then conditions are kept constant by removing waste products and adding new nutrient medium, used to produce primary metabolites
Reduction division
Meiosis, division where each daughter cell has half the genetic material of the parent
Order of events that lead to speciation
Members of a population become isolated, interbreeding stops with rest of population so no gene flow between groups, random mutations and due to selection pressures different characteristics are selected for and agianst, accumulation of mutations and change in allele frequency over generations leads to large changes in phenotype until they can no longer reproduce with the original population so are reproductively isolated
Lamallae
Membranes that join grana
mRNA
Messenger ribonucleic acid. A single stranded template of DNA that is able to leave the nucleus and codes for proteins when it connects to a ribosome
Competitive inhibitors
Molecules similar in shape to the substrate that bind to active site and prevent substrate from entering
Pigment molecules
Molecules that absorb or reflect specific wavelengths of light
Electron acceptors/carriers
Molecules that accept and carry electrons in the light-dependent stages of photosynthesis from the excitation of electrons in chlorophyll a by light
Cause of discontinuous variation
Mostly genetic
Factors affecting evolution
Mutation, sexual selection, gene flow, genetic drift, environmental changes
Factors increasing genetic biodiversity
Mutations in the DNA of an organism create new alleles, interbreeding between different populations - gene flow
The Galapagos Islands control of human activities
National Park created, park rangers introduced, limiting of tourists access to islands or areas, controlling animal migration, strict control of movement of livestock (pigs)
Types of cloning
Natural and artificial
Masai Mara ecostsyem
Nature reserve in Kenya, primarily savannah with fertile grasslands and forests, has annual zebra and wildebeest migrations, large mammals present: black rhino, buffalo, elephants, lions
Penicillium chrysogenum requirements
Needs relatively oxygen levels and a rich nutrient medium, sensitive to pH and temperature, produced by semi-continuous batch process, Penicillin is a secondary metabolite
Terai region ecosysem
Nepal, extremely high biodiversity, fertile, alluvial soils. Thick forests, hot and humid conditions. Bengal tigers and sloth bears present
Cytoskeleton
Network of fibres necessary for shape and stability of a cell
tertiary colonisers
New species of plants with waxy cuticles that protect them from water losses and can survive in conditions without the abundance of water but they need to obtain their water and minerals from the soil
Steps in the process of nitrification
Nitrifying bacteria (such as Nitrosomonas) oxidise ammonium compounds into nitrites (NO2-), other bacteria (Nitrobacter) oxidise nitrites into nitrates (NO3-)
Genus of nitrifying bacterium that oxidises nitrites to nitrates
Nitrobacter
Genus of nitrifying bacteria that oxidise ammonium compounds into nitrites
Nitrosomonas
Why are microorganisms used in biotechnologies?
No welfare issues, enormous range of capabilities, genetics can be easily artificially manipulated by genetic engineering, very short life cycle, rapid growth rate, simple and relatively cheap nutrient requirements, lower costs and temperatures than non-biological processes
Virus
Non living infectious agents, 0.2-0.3x10^-6m, made of DNA or RNA by protein, they invade, control and replicate using host cells, classed as the ultimate parasite
Introns
Non-coding regions of mRNA
Introns
Non-coding regions of pre-mRNA
Abiotic factors
Non-living conditions in a habitat that have direct impact on the organisms that reside there
Abiotic factors
Non-living or physical factors
Abiotic stresses
Non-living/environmental pressures that change and affect plants
Cofactor
Non-protein substances that some enzymes rely on before they can catalyse a reaction.
Undifferentiated cells
Not adapted to any particular function, have the potential to differentiate in to a range of specialised cell types in the organism
Reasons for low efficiency at a consumer level
Not all the biomass of an organism is eaten, some energy is transferred to the environment as metabolic heat, some parts of an organism are eaten but are indigestible so are egested as faeces, some energy is lost in the form as excretory materials such as urine
Reasons for low efficiency at producer level
Not all the solar energy available is used for photosynthesis as most is reflected, some transmitted or at unusable wavelengths, other limiting factors of photosynthesis, some energy 'lost' by photosynthetic reactions
Telophase II
Nuclear membrane reforms around chromosomes which uncoil, cytokinesis occurs producing 4 haploid genetically different cells
RNA editing
Nucleotide sequence of some mRNA molecules can be changed by insertion, deletion or substitution (same effects as base-point mutations) which increases range of proteins produced by one mRNA molecule
Estimated number in population (m^-2)
Number of individuals sample/ area of sample (m^2)
Snowdonia National Park animals present
Numerous bird species: choughs, badgers, deer
Limiting factors preventing theoretical maximum exponential growth rate
Nutrient availability, oxygen levels, temperature, accumulation of toxic waste products, change in pH
Microbial culture media
Nutrient broth (liquid), agar jelly (solid)
Microbial culture media types
Nutrient broth (liquid), agar jelly (solid)
Bilateral symmetry
Observed in most animals where the organisms have bothe left and right, and head and tail
Asymmetry
Observed in organisms that have no lines of symmetry e.g. Sponges
genetic drift
Occurs in small populations where there is a change in the allele frequency due to the random nature of mutation
Primary succession
Occurs on an area of land that has been newly formed or exposed, there is no soil or organic matter present
Secondary succession
Occurs on areas of land where soil is present, but it contains no plant or animal species
Sympatric speciation
Occurs when demes become reproductively isolated from each other, can be prezygotic or postzygotic
Sympatric speciation
Occurs when members of two different species in the same habitat interbreed and create fertile offspring, the hybrid may become reproductively isolated as it can no longer interbreed with either parent population
Antiparallel
One DNA strand is identical to the other but flipped 180'
Balanced diet
One that has a correct proportion of all molecules needed for survival
Main advantage of PCR (according to OCR)
Only a small sample of DNA is needed for PCR amplification
Complementary base pairing
Only specific bases that make the right number of H bonds with a complementary base can pair
Mitochondria
Organelle responsible for the final stages of cellular respiration. Powerhouse of the cell.
Coenzymes
Organic molecules that bind only temporarily to enzymes transferring a chemical group necessary required for the reaction
Multicellular organisms
Organisms made of many specialised cells working together
Unicellular organisms
Organisms that are made of only a single cell
Autotrophic organisms
Organisms that can make complex organic molecules by photosynthesis
ectotherms
Organisms that depend on the environment to warm their bodies
Heterotrophic organisms
Organisms that obtain complex organic molecules by consuming other organisms
Chemoautotrophs
Organisms that obtain energy from oxidation of electron donors in their environment
Heterotroph/Consumer
Organisms that obtain their energy by feeding on other organisms as they are unable to fix carbon from inorganic sources
mutants
Other forms of the wild type allele, results of mutations
Expiration
Out take of breath
Evidence for evolution
Paleontology (the study of fossils and the fossil record), comparative anatomy, comparative biochemistry, comparative embryology
Glucagon
Peptide hormone (secondary structure has one alpha helix) produced by alpha cells of the pancreas. Increases blood glucose concentration
Thermoreceptors in endotherms
Peripheral temperature receptors in skin detect changes in surface temperature, temperature receptors in hypothalamus detect temperature of blood deep in body
Type 2 glucose
Person doesnt produce enough insulin or the persons body cells do not respond properly to insulin
Stages of a population growth curve
Phase 1/slow growth, Phase 2/rapid growth, Phase 3/stable state
Sequence of events of glycolysis
Phosphorylation, lysis, phosphorylation, dehydration and formation of ATP
The glands of the endocrine system
Pituitary, pineal, thyroid, thymus, adrenal, pancreas, ovaries, testes
Photosynthesis
Plant process of creating glucose from carbon dioxide and water by trapping high energy radiation from the sun by chlorophyll
Method by which nitrogen enters a plant
Plants cannot fix nitrogen from the atmosphere directly so absorb nitrogen in the form of highly soluble nitrates from the soil produced by nitrifying bacteria.
What does PCR stand for?
Polymerase chain reaction
Stratified
Populations are divided into strata (sub-groups) based on a particular characteristics based on their size (male and female)
Polymorphic populations
Populations that display more than one distinct phenotype
Herbivory
Predation of plants by animals
Reasons why a predator-prey graph may not be identical to a theoretical one
Predator feeds on multiple prey and finds it easier to prey on the one in greatest supply,
Most famous predator-prey relationship measured
Predator-prey relationship between snowshoe hare and canadian lynx
Aesthetic reasons for maintaining biodiversity
Presence of many species enriches peoples' lives, biodiversity is inspiration for creators, nature relieves stress and decreases recovery time
extrinsic/peripheral protein
Present in one side of bilayer and have hydrophyllic R-groups on their outer surfaces that interact with hydrophyllic membrane or intrinsic proteins
Baroreceptors controlling heart rate
Pressure receptors that detect changes in blood pressure in blood vessels eg aorta, vena cava, carotid arteries
Industrial uses of cytokinins
Preventing ageing of ripened fruit and lettuce, micropropagation to control tissue development
Resons for leaf abscission of deciduous trees
Preventing damage from wind and conservation of energy and water (Loses leaves when amount of glucose used in respiration and chlorophyll production is greater than the amount of glucose produced by photosynthesis)
Types of sympatric speciation
Prezygotic, postzygotic
Types of succession
Primary succession, secondary succession
Alpha cells
Produce and secrete glucagon, are larger and more numerous than beta cells
Beta cells
Produce and secrete insulin
Adaptations of pioneer species/colonisers that allow them to colonise the bare environment
Produce large quantities of seeds or spores which are dispersed by wind to new areas, seeds that germinate rapidly, ability to produce their own
Ovaries
Produce oestrogen and progesterone
Testis
Produce testosterone
Production of insulin
Produced by GM bacteria in bioreactors and pure human insulin extracted in downstream processing
Adrenal gland
Produces adrenaline and noradrenaline
Pituitary gland
Produces growth hormones, ADH, gonadotropins
Pancreas
Produces insulin and glucagon
Pineal gland
Produces melatonin
Thymus gland
Produces thymosin
Thyroid gland
Produces thyroxine
Industrial uses of natural /synthetic auxins
Production of seedless fruit, dicot weedkiller in monocot crops
Apoptosis
Programmed cell death
Industrial uses of ethene
Promote fruit fall in cotton, walnuts and cherries
Thymosin
Promotes growth and maturity of white blood cells
Micropropagation
Propagation of a plant by using selected cells treated with plant hormones (cytokinins) to make it grow into an adult plant
The stages of mitosis
Prophase, metaphase, anaphase, telophase
Antennae complexes
Proteins and pigments that form the light harvesting system of plants. For example chlorophyll b, xanthophylls and carotenoids
Histones
Proteins that associate with eukaryotic DNA to make a tightly coiled structure
Single strand binding proteins (SSBP's)
Proteins used to hold single DNA strands apart, so the hydrogen bonds cannot be reformed, once unzipped.
Adenine
Purine
Guanine
Purine
Cytosine
Pyrimidine
Thymine
Pyrimidine
Practices to maintain the sustainability of fishing
Quotas, reserves, subsidies, using larger net eyes to catch larger fish allowing younger ones to reproduce, reducing the destructiveness of the methods eg not using bomb-fishing
Pre-mRNA
RNA made of introns and exon that needs to be spliced to become RNA
Types of post-transcriptional/pre-translational control
RNA processing
Hybridisation as a main stage of DNA profiling
Radioactive or fluorescent DNA probes are added in excess to the DNA fragments and bind to complementary microsatellite regions. Excess probes washed off
Advantages of using sensors to measure abiotic factors
Rapid changes can be detected, human error in taking the reading is reduced, a high degree of precision, data can be stored and tracked on a computer
Log/exponential phase explanation
Rate of bacterial reproduction is close to or at its theoretical maximum
Erythrocytes
Red blood cells, haemoglobin binds to oxygen for gaseous exchange, flexible fit through capillaries, biconcave shape increase SA for max O2 absorbtion, no nucleus/few organelles more haemoglobin,
Anthocyanins
Red/purple pigments that formed from a reaction between sugars and proteins in cel sap. They are produced when there is a high concentration of augars and high light intensity. They absord blue-green wavelengths and protect chlorophyll from being destroyed
Stage 4 of a predator-prey relationship graph
Reduced predator number cause a low death rate in the prey population so more prey organisms survive and reproduce increasing the prey population. The cycle begins again.
Advantages of propagation from cuttings
Reduced time from planting to crop compared with seeds, guarantees cuttings are genetically identical to good stock used
Polysynaptic reflexes
Reflex arcs that have many synapses because sensory neurones have to connect to many sensory receptors and motor neurones have to connect to many effector
Monosynaptic reflexes
Reflex arcs with only one synapse which increases speed of transmission eg knee jerk reflex
Unconditional reflexes
Reflexes that are innate and not learned
Conditional reflexes
Reflexes that are learned through repeated exposure to a particular set of circumstances or stimuli
Methods of natural cloning in invertibrates
Regeneration entire individuals from fragments of the original individual if they are damaged eg starfish, sponges. Flatworms fragment as part of their normal reproductive process producing clones. Hydra form buds on the side of their body that develop into independent individuals
Exons
Regions of DNA that code for proteins and make up 2% of total DNA
Type 2 diabetes treatment (insulin independent)
Regulation of carbohydrate intake. Injections with drugs that can stimulate insulin production, slow down the rate at which body absorbs glucose from the intestine or insulin injections
Morphogenesis
Regulation of the pattern of anatomical development
Lac operon mechanism
Regulatory gene, lacI expressed producing repressor protein that blocks the operator and promoter regions. In the presence of lactose, lactose binds to the repressor protein changing its shape so that it unhindered and RNA polymerase can transcribe the structural genes by binding to the promoter region
Golgi apparatus
Repackages proteins into Secretory vesicles and adds a carbohydrate or prosthetic group.
Practices to maintain the sustainability of large-scale timber production
Replace every tree cut down with a newly planted tree, try to reduce the destructive methods of the harvesting, reduce the amount of selective harvesting to maintain more biodiversity
Postzygotic reproductive barriers
Reproductive barriers often produced as a result of hybridisation reduce the viabilityor reproductive potential of offspring
Prezygotic reproductive barriers
Reproductive barriers that fertilisation and the formation of a zygote
Blood glucose concentration can decrease by
Respiration, glycogenesis
Genus of nitrogen-fixing bacteria that lives in the root nodules of leguminous plants
Rhizobium
Adaptations of alveoli to increase efficiency of respiration
Rich blood supply maintains steep conc gradients, carry gases to and from alveoli, walls only single epithelial cell decreasing diffusion distance, Large surface area so more diffusion can occur, lung surfactant to keep them open for continuous respiration
Why whilst preparing microbial cultures correct laboratory health and safety procedures must be followed (eg aseptic conditions)?
Risk of mutation that makes the strain pathogenic. Risk of contamination with pathogenic microorganisms from the environment
Why whilst preparing microbial cultures correct laboratory health and safety procedures must be followed?
Risk of mutation that makes the strain pathogenic. Risk of contamination with pathogenic microorganisms from the environment
Bacillus
Rod shaped bacteria
Arguments against animal cloning
SCNT very inefficient process, many clones fail to develop, miscarry or produce malformed offspring, clones have shortened lifespans, SCNT has been relatively unsuccessful in increasing the populations of rare organisms
Non-random sampling
Sample not chosen at random
Systematic
Sampling different areas within an overall habitat are identified
Opportunistic
Sampling organisms that are conveniently available, the weakest form of non-random sampling
Indentifying species (DNA barcoding) as a use of DNA sequencing
Scientists identify particular sections in the genomes of kingdoms that are common to all species but vary between them. In animals: Cytochrome C oxidase part of mitDNA used in respiration. In plants: chloroplast DNA use in photosynthesis.
Chlorophyll b, xanthophylls and carotenoids
Secondary pigments in photosynthesis that absorb different wavelengths of light
Somites
Segments in an embryo that develop into individual segments and their associated structures
Random sampling
Selecting individuals by chance, each individual has an equal likelihood of selection and has no human impact
Negative selection
Selection against a characteristic that is disadvantageous to an organism's survival
Directional selection
Selection pressure toward one extreme moves the mode in the same direction
Stabilising selection
Selection pressure towards the centre increases the number of individuals at the modal value
Disruptive selection
Selection pressure towards the extremes creates two modal values and leads to two different species
Minisatellite/ variable number tandem repeats (VNTVs)
Sequences of 20-50 base pairs that are repeated from 50 to several hundred times at more than 1000 locations in the human genome
Taxonomic groups (Linnaean classification)
Seven group hierarchy system of classifying living organisms
Granum
Several stacked thylakoids
Behavioural responses as a form of thermoregulation in ectotherms (and endotherms) to decrease body temperature
Shelter from sun by seeking shade, digging burrows, press bodoes against cool earth or stones, orietntate bodies to minimise surface area exposed, minimise movement to reduce metabolic reactions, aestivation (hibernation in hottest weather)
Satellite DNA
Short sections of DNA that are repeated many times within introns, telomeres and centromeres
Metaphase II
Single chromosome line up on metaphase plate, Spindle fibres attach to sister chromatids
Cytoplasm
Site of many aqueous cellular reactions
Androgens
Small amounts of male and female sex hormones that have a relatively small effect compared to testosterone amd oestrogen
Negative feedback system
Small change outside parameters detected by sensory receptors, effectors work to reverse the change and restore the conditions to their base levels
Snowdonia National Park control of human activities
Snowdonia National Park Authority formed which: conserves and enhances natural beauty and wildlife, promote sustainable ways to enjoy park, enhance local communities by providing jobs. Have built rock footpaths. Dinorwig HEPS deep in mountain provides energy without affecting beauty of area
Indirect transmission
Soil contamination and vectors
Plant responses to prevent freezing
Solutes in the cytoplasm that lower the freezing point eg salts, sugars, polysaccharides, amino acids, proteins
Effector
Something that produces a coordinated change in response to a stimulus
Restriction endonucleases
Special enzymes that that cut the DNA double helix in to places, one on each strand at a recognition site
Level of organisation in multicellular organisms
Specialised cell>tissues>organs>organ systems>whole organism
Isolation of the desired gene in genetic engineering if the locus of the gene is known
Specific restriction endonucleases used to cut the DNA in 2 places producing sticky ends
Coccus
Spherical bacteria
Spirillum
Spiral shaped bacteria
The law of limiting factors
States that the rate of physiological process will be limited by the factor in the shortest supply
Totipotent
Stem cells that can differentiate into any type of cell
Types of hormones
Steroid and non-steroid
Progesterone
Steroid female sex hormone responsible for the menstrual cycle, pregnancy and embryogenesis in humans
Plant response to changes in water
Stomatal control
Gene bank
Stores of biological samples, other than seeds, such as sperm or eggs that are usually frozen
Digestion of sample as a main stage of DNA profiling
Strands of DNA are cut into smaller fragments using restriction endonucleases that cut each DNA strand at a recognition site, they cut the DNA in the intron regions
tertiary structure of proteins
Stronger bonds between secondary structure polypeptides inc. ionic, hydrophobic/hydrophillic interactions, disulfide bridge and hydrogen bonding
Inhibitor
Substances that affect enzyme action by making enzymes inactive
Primary metabolites
Substances which are essential to the normal growth of microorganisms, produced in log phase, e.g. Ethanol
Secondary metabolites
Substances which are not essential for normal growth, but are still used by cells, produced in stationary phase e.g. Penicillin
Specialised exchange surfaces
Surfaces that are adapted and specialised to function as an efficient gas exchange system
Radial symmetry
Symmetry observed in diploblastic animals where they have no right or left sides just a top and bottom e.g. Jellyfish
Antidiuretic hormone, ADH
Synthesised in the hypothalamus, stored and released by posterior pituitary gland in response to a drop in water potential of blood, has an effect on walls of collecting duct and DCT by moving aquaporins to surface increasing water reasborption
A ->
T
Sampling
Taking measurements of a limited number of individual organisms present in a particular area
Aseptic techniques
Techniques used to reduce the risk of contamination
Aseptic techniques
Techniques used to reduce the risk of contamination by keeping the environment around microorganisms sterile
Conditions that need to be kept controlled in bioreactors
Temperature, pH, nutrients and oxygen, mixing, asepsis
fever reasons
Temperatures higher than 37'C inhibit pathogen reproduction; the specific immune system works better at a higher temp
Types of prezygotic sympatric speciation
Temporal, ecological, gametic, polyploidal, behavioural, mechanical
oxaloacetate
The 4C regenerate of Kreb's Cycle
Determination of evolutionary relationships (phylogeny) between species
The DNA sequences of different species can be compared and the differences in their base sequence assumed to be caused by mutation. If the mutation rate is known the time since the 2 species shared a common ancestor can be calculated and a phylogenetic tree constructed
The Lake District National Park control of human activities
The Lake District National Park Authority created, actively manages area in a similar way to Snowdonia National Park Authority, replant native tree species
Antibiotic resistance
The ability of bacteria and other microorganisms to resist the effects of an antibiotic to which they were once sensitive due to natural selection (antibiotic acts as selection pressure, resistance is advantageous characteristic)
Contrast
The ability to distinguish between individual objects due to their difference in colour or shade
Innate or instinctive behaviour
The ability to do something is inherited through genes
Resolution
The ability to see individual objects as seperate entities
Behavioural adaptations
The adaptation in the way an organism behaves; can be inherited or learnt
wild type allele
The allele coding for the most common/normal characteristic
Dead space
The amount of air in the bronchioles, bronchi and trachea (where no gas exchange occurs).
Replication bubble
The area of DNA unzipped by DNA helicase from the replication fork to where the bases rejoin
Seperation zone
The area on the base of a leaf petiole where the leaf falls from in leaf abscission
Chemosynthesis
The biological conversion of one or more carbon containing molecules and nutrients in to organic matter using the oxidation of inorganic compounds or methane as a source of energy
Endocrine system
The bodily system made up of endocrine glands that secrete hormones directly into bloodstream
inbreeding
The breeding of closely related individuals within a species' population
Bundle of His
The bundle of cardiac muscle fibers that conducts the electrical impulses that regulate the heartbeat, from the AVN in the right atrium to the septum between the ventricles and then to the left and right ventricles.
Optimum pH
The certain H ion conc at which the active site will be the right shape, thus the pH with the highest rate of reaction
Coenzyme NADP
The coenzyme important in photosynthesis that is reduced by the addition of 2e- and 2H+ from non-cyclic phosphorylation and photolysis and transfers them to TP to form GP in Calvin's Cycle
Enzyme-substrate complex
The complex between an enzyme nd substrate by weak bonds
Enzyme-inhibitor complex
The complex formed between an inhibitor and enzyme by bonds
Spliceosome
The complex of enzymes responsible for cutting out introns from mRNA. Made of restrictive and RNA Ligase enzymes
Epigenetics
The control of gene expression by the modification of DNA
Countercurrent multiplier
The creation of very concentrated urine by creation of a very low water potential in the renal medulla to allow for more water reabsorption
(Woes's) Three Domain System of classification
The current scientifically accepted classification system that uses 3 domains that are higher than kingdoms in the taxonomical hierarchy, based on differences in the ribosomal RNA (rRNA), cells' membrane lipid structure and sensitivity to antibiotics
Bioinformatics
The development of the software and computing tools needed to organise and analyse raw biological data, including the development of algorithms, mathematical models, and statistical test that help to interpret enormous quantities of data
Error (of measurement)
The difference between an individual measurement and the true value/accepted reference value of the quantity being measured
Interspecific variation
The differences between individuals of different species
Intraspecific variation
The differences between individuals of the same species
Genetic engineering
The direct manipulation of an organism's genomeusing biotechnology
Carbon cycle
The ecological cycle that recycles carbon in the environment
Nitrogen cycle
The ecological cycle that recycles nitrogen in the environment
Competitive exclusion principle
The ecological rule that states that where two species are competing for the same resources or occupy the same niche, the one that uses the resources more effectively or that is better adapted will ultimately eliminate the other species
Ecological efficiency
The eficiency with which biomass or energy is transferred from one trophies level to the next
Lock-and-key theory of enzyme action
The enzyme has a specific active site that is conplementary to the shape of the substrate
artificial selection/selective breeding
The evolution of a population due to the selection pressures caused by humans selecting the individuals with the most desirable characteristics to reproduce
Phylogeny
The evolutionary relationships between organisms
Expiratory reserve volume
The extra amount of air you can force out of your lungs over and above the normal tidal volume of air you breathe out
Genomics
The field of genetics that applies DNA sequencing methods and computational biology to analyse the structure and function of genomes
climax community
The final stage in a primary ecological succession, characterised by a stable statethat doesn't change a lot over time, normally with a few dominating plant or animal species, has a relatively low biodiversity compared to other seral stages
Generic name
The first name of an organism's Binomial nomenclature; its genus
pioneer species/primary colonisers
The first organisms to colonise an inhospitable environment, arrive as spores or seeds by wind dispertion or animal dispertion
Speciation
The formation of new species through the process of evolution
Speciation
The formation of new species when gene flow is effectively stopped between populations where it previously existed
Triplet code
The genetic code is made of 3 bases coding for one amino acid
Non-overlapping
The genetic code is non-overlapping because each triplet is read independently
Environmental gradient
The gradual change of abiotic factors across a linear area eg light intensity, altitude, water availability
Kymograph
The graph of lung volume vs. time produced by a spirometer
Chemotropism
The growth of plants in response to chemicals
Phototropism
The growth of plants in response to light which comes from one direction (unilateral light)
Geotropism
The growth of plants in response to the direction of gravity
Thigmotropism
The growth of plants in response to touch
Stage 2 of a predator-prey relationship graph
The increased predator population eats more of the prey causing a decline in the prey population
Adrenal medulla
The inner region of the adrenal gland that secretes non-essential hormones like adrenaline and noradrenaline released when the sympathetic nervous system is stimulated when body is stressed
Epistasis
The interaction of genes at different loci eg when a gene codes for the production of an enzyme that changes the protein of another gene. If the enzyme isn't produced the protein isn't changed so the second gene's geotype has no effect
Introns
The large regions of DNA that do not code for proteins
Self-regulated system of maintaining blood glucse concentration
The level of glucose in the blood that determines the quantity of insulin and glucagon that is released
Matrix
The liquid interior of mitochondria
Mature mRNA
The mRNA product of splicing, RNA made up of only exons
Biomass
The mass of living material present in a particular place or in particular organisms
Inspiratory reserve volume
The maximum volume of air you can breathe in over and above the normal inhalation
Tonoplast
The membrane surrounding the vacoule
Microbial culture
The method of multiplying microbial organisms by letting them reproduce in predetermined culture media under controlled laboratory conditions.
The Fluid Mosaic model
The model of a phospholipid bilayer, in which the molecules are free to move relative to each other (fluid), giving flexibility and is embedded with different shape, size and position proteins (mosaic).
Degradation of mRNA
The more resistant to degradation the mRNA molecule is, the longer it will stay in the cytoplasm, the greater quantity of proteins will be synthesised from it
gene flow
The movement of alleles between populations due to immigration and emigration which result in different allele frequencies
intermediate community
The multiple seral stages between the pioneer community and the climax community characterised by the presence of secondary and tertiary colonisers, better adapted organisms outcompete the less well-adapted and dominate so are the most abundant in terms of mass, has the highest relative biodiversity
Breathing rate
The number of breaths taken per minute
Habitat biodiversity
The number of different habitats found within an area
Species richness
The number of different species living in a particular area
Carotene
The orange carotenoid
Parent DNA
The original DNA that replicates
Adrenal capsule
The outer region of the adrenal glands that secrete essential hormones like cortisol and aldosterone, glucocorticoids, mineralocortoids, androgens
Chiasma
The point at which two chromosomes cross over
Locus
The position
Hydrogen bonds
The positive charge on the hydrogens due to oxygen having a higher nuclear charge causes weak chemical bonds. This makes water difficult to evaporate so lots of energy is needed and it makes water stable due to the high incidences of them.
Repeatability
The precision obtained when measurement results are produced over a short timescale by the same person/group using the same apparatus in the same place
Reproducibility
The precision obtained when measurement results are produced over a wider timescale by different people using equivalent apparatus in different but equivalent places
Chlorophyll a
The primary pigment of photosynthesis
Reaction centre
The primary pigment part of a photosystem
Nitrification
The process by which ammonium compounds in the soil are converted, by nitrifying bacteria, into nitrogen-containing molecules that can be used by plants. Is an oxidation reaction so only occurs in well-aerated soils
Ammonification
The process by which decomposers convert nitrogen-containing molecules in dead organisms, faeces and urine into ammonium compounds
Glycogenolysis
The process by which glycogen stored in the liver and muscle cells is broken down into glucose which is released into blood stream
Classification
The process by which living organisms are sorted into groupson the basis of shared features
Amplification of DNA
The process of copying DNA to produce a very large amount of it from a very small amount to be used in DNA profiling
DNA sequencing
The process of determining the precise order of nucleotides within a DNA molecule
Cell signalling
The process of how cells communicate consists of hormones binding to glycoproteins on surface causing a change or antigens used to recognise neighbouring cells
Nitrogen fixation
The process of incorporation nitrogen from the atmosphere by bacteria into other nitrogen compounds (ammonia) that can be used by plants
Micropropagation
The process of making large numbers of genetically identical offspring from a single parent plant using a tissue culture techniques
Gluconeogenesis
The production of glucose from non-carbohydrate sources eg glucose can be made by the liver from lipids and amino acids
Glycogenesis
The production of glycogen by converting it into glycogen and stored in liver
Stage 3 of a predator-prey relationship graph
The reduced prey population can no longer support the predator population (it has exceeded the carrying capacity) and intraspecific competition for food in the predator population increases, resulting in a decrease in t he size of the predator population
Predator-prey relationship
The relationship between a predator and its prey in alternating periods of growth and decline over time
allele frequency
The relative frequency of a particular allele in a population
RNA processing/Splicing
The removal of introns by a spliceosome from pre-mRNA to produce mature mRNA made up of only introns, a cap and tail are added too to show the start and end
Ventral root
The root
Dorsal root
The root that feeds into the spinal cord from sensory neurones
Why is the genetic code described as universal?
The same codon codes for the same amino acid in all organisms
Specific name
The second name of an organism's Binomial nomenclature; its species
Photoperiodism
The sensitivity of plants to the lack of light in their environment
Abscission zone
The seperation zone and the protective layer
Metabolism
The set life sustaining reactions within cells of living organisms
Catabolic
The set of metabolic pathways that breaks down molecules into smaller units
Anabolic
The set of metabolic pathways that construct molecules from smaller units
A.T.P. (adenoine triphosphate)
The source of energy for cellular process. Made of deoxyribose bonded to an adenine base and 3 inorganic phosphate ions which can be hydrolysed to release the energy stored in the bonds
Leading strand
The strand going from 3' to 5' towards the replication fork makes a complete copy strand
Lagging strand
The strand going from 5' to 3' from the replication fork, so Okazaki fragments are made by DNA polymerase
Genomics
The study of all genes of an organism
Computational biology
The study of biology using computational techniques, especially in the analysis of huge amounts of biodata
Phylogenetics
The study of the evolutionary history of groups of orgnisms
Ecology
The study of the relationships between organisms and their environment
Chromatin
The substance from which chromosomes are made .
Total lung capacity
The sum of the vital capacity and the residual volume
gene pool
The sum total of all the genes in a population at a given time
Optimum temperature
The temp at which the enzyme has the highest rate of activity
Cell theory
The theory that all living things are composed of cells or cell products
Evolution
The theory that describes the way in which organisms change over time due to natural selection
Cohesion-tension theory
The theory that explain the movement of water up xylem by the pulling of water up the xylem by cohesion
Apical dominance/lateral dormancy
The topmost shoot of a plant will grow the strongest because of the highest conc of auxins and side shoots will grow less due to the lower conc of auxins
Gene pool
The total information from all the genes and alleles of the breeding individuals in a population at a particular time
community
The total populations of each species in a given area at a given time
Anticodon
The triplet of bases on tRNA complementary to a codon
Replication fork
The two strands of DNA that are immediately unzipped by DNA helicase
Polarity
The uneven distribution of charged particles causes water molecules to be dipolar and dissociate some substances
Surface tension
The uneven distribution of forces creates a skin able to support small insects
Genetic biodiversity/gene pool
The variety of genes that make up a species
Biodiversity
The variety of living organisms present in an area
Genetic biodiversity
The variety of the genes that make up a species
Vital capacity
The volume of air that can be breathed in when the strongest possible exhalation is followed by the deepest possible inspiration
Residual volume
The volume of air that is left in your lungs when you have exhaled as hard as possible
Tidal volume
The volume of air that moves in and out of the lungs with each resting breath
Binomial nomenclature
The way of naming organisms in Linnaean classification where the first name is their genus and the second their species
Xanthophyll
The yellow carotenoid
Examples of negative feedback system
Thermoregulation in enotherms, osmoregulation, blood glucose level, blood pH
Example of a negative feedback system
Thermoregulation, osmoregulation
Multipotent
These cells can only form a range of cells within a certain type of tissue
Pluripotent
These stem cells can form all tissue types but not whole organisms
carrier protein
They have an important role in active transport, transporting particles in the opposite direction of the conc. gradient and need energy.
Why do enzymes increase rate of reaction?
They lower the activation energy needed for a biological reaction to start
Mode of transport of hormones from glands to target cells
Through blood plasma
Why is PCR done?
To amplify a sample strand of DNA to be sequenced/profiled
Analysing the genomes of pathogens as a use of DNA sequencing
To find the the source of an infection, to identify antibiotic-resistant strains of bacteria, to monitor the progress of a potential epidemic (mutations in pathogens), to identify regions on pathogen's genome that can be targets in the development of new drugs, to identify genetic markers for use in vaccines
Reasons why scientists classify organisms
To make identification of organisms easier, to predict characteristics of related species, to find evolutionary links like common ancestors if species share the same characteristics
Stationary phase explanation
Total growth rate is zero, rate at which cells are dividing is equal to the rate at which cells are dying
Ventilation rate
Total volume of air inhaled in one minute
Masai Mara conservation and research
Trained reserve rangers employed to stop illegal black rhino poaching. Scientific research projects undertaken to investigate: Mara river flow, and monitor: lion, cheetah and hyena populations
Microtubules
Tubes of polymerised tubulin. Scaffold-like they determine cell shape and act as tracks for organelle movement e.g. vesicles
Centrosome
Two associated centrioles
Disaccharides
Two monosaccharides bonded by a glycosidic bond, condensation reaction
Belt transect
Two parallel lines are marked and samples are taken of the area between the area
Stem cells
Undifferentiated cells that have the potential to differentiate in to a range of specialised cell types in the organism
Somatic cell nuclear transfer
Unfirtilised egg is enucleated, somatic cell from sheep to be cloned is taken and cultured and the nucleus removed and fused with enucleated ovum, embryo transferred to the uterus of a third sheep that acts as a surrogate mother which gives birth to the cloned sheep which is genetically identical to the sheep that gave the somatic cell
Magnification of light microscope
Up to x2,000
Magnification of electron microscopes
Up to x500,000
Industrial uses of gibberellins
Used to delay ripening and ageing in fruit, to improve size and shape of fruits, speed up malting process in ber brewing
Selective toxicity
Used to describe antibiotics as they are only toxic against the microorganisms causing the disease and not the host cells
Kick sampling
Used to study river organism, sediment is kicked up and a net downstream catches any organisms for a set period of time
Atomic force microscope
Uses a cantilever with a tip that scans the surface atoms of a specimen, experiencing a repulsion force. This varies the place on the detector where the laser beam reflects off the cantilever and produces a 3D image of the surface
Super resolved fluorescence microscopy
Uses images from a molecular sized point from a normal laser scanning confocal microscope to build a super resolved image
Types of bioremediation
Using natural organisms, using GM organisms
Genetic causes of variation
Variant alleles, mutations, meiosis (independent assortment and crossing over), sexual reproduction, random fertilisation
Measuring species richness
Various techniques should be used to compile list of species in habitat. Then total is a measure of species richness
Natural cloning in plants is also called
Vegetative propagation
trachea
Vessel that transmits air from nasal cavity to lungs, has cartilaginous C rings to keep airways open and ciliated epithelial cells to move mucus and catch dust
Bacteriophages
Viruses that attack bacteria
Vitamins
Vital amines, 9 that humans need from the things they eat and cannot produce themselves
environmental causes of temperature increase in organisms
Waste heat from cellular respiration, convection, conduction and radiation from environment
Amphoteric (ability of a substance to be an acid or base)
Water acts as a pH buffer to all enzyme reactions.
High specific heat capacity
Water acts as a temperature buffer which helps maintain constant temperature to optimise enzyme activity
Latent heat of fusion (The amount of heat evolved for a substance to turn into a solid)
Water in cells and aquatic environments are slow to freeze maintaining a stable environment.
Fluidity
Water is fluid in a large range of temps, allowing for stability in biological processes and metabolic reactions
Compression
Water is hard to compress meaning its a very good support medium e.g. turgor in plants.
Photolysis
Water is seperated into 1/2 O2, 2 e- and 2 H+ by the use of sunlight and enzymes
Viscosity
Water's low viscosity allows it to flow and lubricate
Molecular mobility
Weak hydrogen bonds allows molecules to move easily, which allows osmosis
Haemoglobonic acid
When Hb bonds with a H+ ion to make HHb
Cyclic phosphorylation
When PSI absorbs light and releases 2 e- to an electron acceptor then they go along an e.t.c phosphorylating ADP to ATP and are absorbed by the deficient PSI
Disruptive selection
When a change in the environment selects for the extreme phenotypes and the norm is selected against
Directional selection
When a change in the environment that makes the most common phenotype no longer the most advantageous so less common extreme phenotypes are positively selected, evolution occurs as the allele frequency shifts to the extreme phenotypes
Founder effect
When a few individuals of a species colonise a new area, their offspring initially experience a look of genetic variation
Major histocompatible complex (MHC)
When a macrophage ha digested a pathogen, it combines antigens from the pathogen's surface membrane with special glycoproteins in the cytoplasm called this
Precursor activation
When a precursor enzyme undergoes a change in shape (particularly in tertiary structure) to be activated
Transcription
When a relevant gene is copied into mRNA
Antigen-antibody complex
When an antibody bonds to an antigen of a pathogen (this can also act as an opsonin)
Validity of an investigative procedure is decreased
When an investigative procedure does not have any control groups
Artificial passive immunity
When antibodies for a specific antigen are extracted from an animal and injected as a short term solution to some diseases eg tetanus and rabies
Facilitated diffusion
When channel proteins provide a hydrophilic route for charge molecules to pass through a cell membrane along a concentration gradient
Allopatric speciation
When members of a population are isolated from the rest of the group by a physical barrier and are geographically isolated, selection pressures will result in speciation and if small groups the founder effect will occur causing genetic drift
Limiting factors in photosynthesis (definition)
When one factor of photosynthesis is in short supply it reduces the rate of photosynthesis
Selective breeding (artificial selection)
When organisms with favourable characteristics are specially chosen by humans to met and produce offspring with even better characteristics
Decline/death phase explanation
When rate of reproduction has almost ceased and the death rate is increasing
Translation
When ribosomes read mRNA
Induced fit theory of enzyme action
When substrate enters the active site it induces changes in the tertiary structure of the active site that strengthen binding, putting strain on substrate. This weakens bonds in substrate and causes activation energy to be lowered
End-product inhibition
When the amount of a product is high it binds non competitively to an enzyme pathway blocking further production
Stabilising selection
When the norm or average is selected for and the extremes are selected against
Reproductive isolation
When two demes of the species are isolated and can no longer interbreed
Outcompetition
When two species competing for the same resources the less well adapted species is outcompeted by the more adapted species
Convergent evolution
When unrelated species begin to share similar traits because the organisms to similar environments or other selection pressures
Specimen stage
Where the slide and specimen are placed for viewing
Abiotic factors list
Wind speed, light intensity, relative humidity, pH, temperature, oxygen content in water
Vectors
Wind, water, animals, humans
Noradrenaline
Works with adrenaline in response to stress, causing increased heart rate, widening of pupils, widening air passages in lungs and narrowing of blood vessels in non-essential organs resulting in a higher blood pressire
Antibodies
Y-shaped glycoproteins called immunoglobulins which bind to the specific antigen on the pathogen or toxin that has triggered the immune response
Prosthetic group for carbonic anhydrase
Zn+
antagonism
a (plant) response where different (plant) hormones that inhibit each other, giving a lesser or balanced response than on their own
synergism
a (plant) response where different (plant) hormones work together by complementing each other, giving a greater response than on their own
citric acid/citrate
a 6C compound that is formed from oxaloacetate and acetate
Casparian strip
a band of waxy material called suberin that runs around each of the endodermal cells forming a waterproof layer
Carbohydrates
a biological molecules made of only the elements C and H
tannin
a bitter, astringent-tasting chemical that protects plants from consumption by herbivores
Immunological response
a bodily defense reaction that recognizes an invading substance (an antigen: such as a virus or fungus or bacteria or transplanted organ) and produces antibodies specific against that antigen
Mast cells
a cell filled with basophil granules, found in numbers in connective tissue and releasing histamine and other substances during inflammatory and allergic reactions
threshold value
a certain level of a stimulus that when higher than the threshold value always triggers a response
stimulus
a change in an organism's internal or external environment
depolarisation
a change in potential difference of axon from -70mV to +40mV when the stimulus energy is used by sensory receptor to flip the charges on axon
Mutation
a change in the sequence of bases in DNA
mutagens
a chemical, physical, or biological agent which increases the rate of mutations
Cytokinesis in animal cells
a cleavage furrow forms and the cell-surface membrane is pulled inwads by cytoskeleton, until it fuses
sinoatrial node (SAN)
a cluster of cells situated in the right atrium that generate the wave of excitation
Glycosidic bond
a covalent bond between two saccharides
Monoculture
a cultured crop of clones meaning they are all genetically identical
peak flow meter
a device that measures the rate at which air can be expelled from the lungs
Sucrose
a disaccharide made of a glucose and fructose in a condensation reaction
Lactose
a disaccharide made of glucose and galactose in a condensation reaction
Maltose
a disaccharide made of two α glucose monosaccharides, condensation reaction
polyunsaturated
a fatty acid chain with many (n) double bond, bent
Saturated
a fatty acid chain with no double bonds, straight
monounsaturated
a fatty acid chain with one double bond, slightly bent
fermentation
a form of anaerobic respiration that is the process by which complex organic compounds are broken down into simpler inorganic compounds without the use of oxygen or the involvement of an e.t.c.
oncotic pressure
a form of osmotic pressure exerted by proteins, notably albumin, in a blood vessel's plasma (blood/liquid) that usually tends to pull water into the circulatory system.
anaerobic respiration
a form of respiration using electron acceptors other than oxygen
DNA/hybridisation probe
a fragment of single stranded DNA or RNA which is radioactively/fluorescently tagged and is complementary to specific satellite region in the DNA sample
Structural gene
a gene that codes for any RNA or protein product other than a regulatory factor
Population growth curve
a graph of number of organisms against time showing their slow then rapid growth and stable state in three stages/phases
ganglion
a group of nerve cell bodies located in the autonomic nervous system
Species
a group of organisms that are able to reproduce to produce fertile offspring
galactose
a hexose monosaccharide, an isomerism of glucose
Adenosine diphosphate (ADP)
a hydrolysed ATP that has lost a phosphate group
pancreas
a large gland behind the stomach which secretes digestive enzymes into the duodenum. Embedded in the pancreas are the islets of Langerhans, which secrete into the blood the hormones insulin and glucagon.
Biome
a large naturally occurring community of flora and fauna occupying a major habitat, e.g. forest or tundra.
inflammatory response
a localised response to pathogens (or damage or irritants) resulting in inflammation at the site of a wound, charachterised by pain, heat, redness and swelling
Loop of Henle
a long loop of tubule that creates a region with a very high solute concentration in the tissue fluid deep in the kidney medulla
Interphase/resting phase
a long period of growth and normal function of a cell
root hair
a long, thin expansion from a root hair cell, a specialised epidermal cell found near the growing root tip
Callus
a mass of identical undifferentiated cells formed when the sterilised sample is placed in a sterile culture medium in micropropagation
Artificial immunity
a mean by which the body is given immunity to a disease by intentional exposure to small quantities of it.
transport system
a means by which materials (oxygen, nutrients) are transported from an exchange surface/s to individual cells
Recombination frequency (definition)
a measure of the amount of crossing over that occurs during meiosis
Accuracy
a measure of the closeness of agreement between an individual test result and the true value (accepted value may be used as true value often not known)`
stethoscope
a medical instrument for listening to the action of someone's heart or breathing, typically having a small disc-shaped resonator that is placed against the chest, and two tubes connected to earpieces.
anti-pyretic
a medicinal chemical that reduces fevers
Lung/pulmonary surfactant
a mixture of lipids and proteins which is secreted by goblet cells on to the inner surface of alveoli. Its main function is to reduce the surface tension at the air/liquid interface in the lung
sarcoplasmic reticulum
a modified version of the endoplasmic reticulum that extends throughout the muscle fibre and contains calcium ions required for muscle contraction
Acetyl coenzyme A (acetyl CoA)
a molecule formed by the addition of CoA to a acetyl group
respiratory substrates
a molecule from which energy can be liberated to produce ATP in a living cell.
amphiphillic
a molecule that has hydrophobic and hydrophillic properties
Vitalographs
a more sophisticated peak flow meter that produces a a graph of the amount the person breathes out and how quickly it is breathed out
nonsense mutations
a mutation that results in a STOP codon
missense mutations
a mutation that results in a different amino acid being coded for
plasmodesmata
a narrow thread of cytoplasm that passes through the cell walls of adjacent plant cells and allows communication between them.
lymphatic system
a network of tissues and organs that help rid the body of toxins, waste and other unwanted materials. The primary function of the lymphatic system is to transport lymph, a fluid containing infection-fighting white blood cells, throughout the body.
aestivation
a period of deep sleepsimilar to hibernation that occurs in the hottest/driest season to reduce heat stress
hibernation
a period of dormancy during the coldest weather to conserve energy and reduce cold stress
Aestivation
a period of inactivity in hot, dry environments a combination of behavioural and physiological adaptation
Antigen presenting cell (APC)
a phagocyte with MHC/antigen complexes on it's cell surface membrane, which can stimulate other cells in the specific immune system
apoenzyme
a precursor enzyme before a cofactor has been added
Etoliation (as an example of a characteristic in plants that is a result of environmental variation and genetic variation)
a process in flowering plants grown in partial or complete absence of light. It is characterized by long, weak stems; smaller leaves; and a pale yellow color due to chlorosis
response
a processed and appropriate coordinated change to counteract or in response to a stimuli
ADH
a protein hormone, primary mechanism, non-steroid it triggers cAMP that is secondary messenger and triggers ATP synthase to move vesicles with aquaporins to cell membrane of collecting duct cells
Polypeptide
a proteins chain made of many amino acids joined together by peptide bonds
Confidence
a qualitative judgement expressing the extent to which a conclusion is justified by the quality of the evidence
Promoter region
a region of DNA that initiates transcription of a particular gene
Centromere
a region where chromatids are joined together. Necessary to keep chromatids apart and so they can be moved precisely in mitosis
A sustainable resource
a renewable resource that is being economically exploited in such a way that it will not diminish or run out
Gene bank
a repository of genetic material to maintain genetic diversity
Cyclic adenosine mono-phosphate (CAMP)
a secondary messenger activated by adrenaline which activates other enzymes in liver
inversion (as a type of chromosomal mutation)
a section of a chromosome breaks off, is reversed, and then joins back onto the chromosome
translocation (as a type of chromosomal mutation)
a section of one chromosome breaks off and joins another non-homologous chromosome
electron transport chain
a series of compounds that transfer electrons from electron donors to electron acceptors of successively lower energies via redox reactions, and couples this electron transfer with the transfer of protons (H+ ions) across a membrane.
refractory period
a short period of time when the axon cannot be excited again ( the VGIC's are closed preventing the movement of sodium ions into axon)
oxygen dissociation curve
a sigmoid curve of a graph of % saturation of Hb with O2 against pO2
Intraspecific competition graph shape in terms of trig
a sine graph translated in the positive y-direction
atrio-ventricular node (AVN)
a small mass of muscular fibers at the base of the wall between the atria, conducting impulses received from the sinoatrial node
gall bladder
a small organ where bile is stored and concentrated before it is released into the small intestine
Vulnerable
a species that is considered likely to become endangered in the near future
Endangered
a species that is in danger of extinction
Phase 3 as a stage of a population growth curve
a stable state where further population growth is prevented by external limiting factors. Population size fluctuates but overall size is relatively stable as birth rate and death rate are approximately equal
Deflected succession
a stable vegetation community arising from an ecological succession that has been deflected or arrested directly or indirectly as a result of human activities.
Metabolites
a substance produced by cellular metabolisms
Southern blotting
a technique used to transfer single stranded DNA fragments from a gel electrophoresis gel to a nylon membrane retaining their positions
Interleukins
a type of cytokine cell-signalling molecule that stimulates lots of parts of the active immune system
Anomaly/outlier
a value in a set of results that is judged not to be part of the inherent variation
Disulfide bond/bridge
a very strong bond between 2 sulfur atoms of the R groups of cystene
(blood) plasma
a yellow fluid, mostly water that carries dissolved glucose and amino acids, mineral ions hormones and large plasma proteins inc. albumin, fibrinogen and globulins, carries erythrocytes and platelets
formation of citric acid of Kreb's Cycle
acetate (2C) along with the 4C regenerate of Kreb's Cycle - oxaloacetate forms citric acid (6C)
conversion of Kreb's Cycle
acetyl CoA is converted into acetate and CoA is released
Peat bogs ecosystem
acidic, anaerobic conditions, wet boggy. Support wide range of mosses and rare insects. Lack of predators, human impacts and exposed areas good for birds of prey
protein kinases
activated by cAMP and they phosphorylate and activate other enzymes
phosphorylation
addition of a phosphate group
Conservation agreements
agreements for the local, and international cooperation to ensure habitats and individual species are preserved
Examples of pioneer species/primary colonisers
algae, lichen
reducing sugars
all monosaccharide and some disaccharides (lactose, maltose) that can donate electrons or reduce another molecule or chemical
stage of reabsorption that occurs in proximal convoluted tubule
all of the glucose, amino acids, vitamins and hormones reabsorbed by active transport, ~85% of water and NaCl by following passively down concentration gradients
peripheral nervous system, PNS
all the neurones that connect the CNS to the rest of the body (sensory neurones, motor neurones)
Transparency
allows aquatic plants to photosynthesise
Arguments for micropropagation
allows for rapid production of large numbers of clones of known genetic make-up and high-yield crop, culturing meristem tissues produces disease-free plants, allows proliferation of GM plants, can make large numbers of sterile plants (with seedless fruit eg bananas and grapes), way of growingnaturally relatively infertile plants or ones that are difficult to grow from seed, reliably can increase numbers of rare or endangered plants
elastic recoil
alveoli are mostly composed of elastin, which allows them to stretch during inspiration and return to resting shape when expiration occurs
arrhythmia
an abnormal rhythm of the heart
holoenzyme
an activated precursor enzyme with a cofactor added
Monoclonal antibodies
an antibody produced by a single clone of cells or cell line and consisting of identical antibody molecules.
Wildlife reserves
an area of land that is protected and managed in order to preserve a particular type of habitat and its flora and fauna which are often rare or endangered. Active management is required
Chromatid
an arm of a chromosome that is identical to the other chromosome arm
Multiple sclerosis
an autoimmune neurological condition that destroys the myelin sheath and disrupts muscle movement, balance and vision
Limiting factors (populations)
an environmental resource or constraint that limits population growth
carbonic anhydrase
an enzyme in rbcs that catalyses the formation of carbonic acid (H2CO3) from water and carbon dioxide
thromboplastin in blood clotting
an enzyme that triggers a cascade of reactions resulting in the formation of a thrombus (blood clot)
Botanic gardens
an establishment where plants are grown for scientific study and display to the public where plant species are actively managed to provide them with the best resources to grow
Uncertainty
an estimate attached to a measurement which characterises the range of values within which the true value is asserted to lie eg 29.5±0.1cm
Competition
an example of a biotic factor and is the result of the interactions between organisms for a limited amount of resources, space or mates
Seed bank
an example of a gene bank where seeds are carefully stored by drying and freezing maintaining their viability by slowing down the rate at which they lose their ability to germinate, so that new plants may be grown in the future. Almost all temperate seeds and many tropical seeds can be store this way
atrial fibrilation
an example of arrhythmia, rapid electrical impulses are generated in the atria and they fibrilate >400/min, can affect ventricle contraction
acetylcholine
an excitatory neurotransmitter, controlled by the parasympathetic nervous system
flavin adenine dinucleotide (FAD)
an hydrogen acceptor that transports hydrogen atoms from the Kreb's Cycle to the e.t.c. by redox reactions, accepts 2 hydrogens, oxidises at the second protein of the e.t.c.
Nicotinamide adenine dinucleotide (NAD)
an hydrogen acceptor that transports hydrogen atoms from the glycolysis, link reaction and Kreb's Cycle to the e.t.c. by redox reactions, accepts 1 hydrogen, oxidises at the start of the e.t.c.
dichotomous key
an identification key where the sequence and structure of identification steps is fixed by the author of the key. At each point in the decision process, multiple alternatives are offered, each leading to a result or a further choice
Autoimmune response
an immunological response that is too powerful and damages the organism's cells as a result causing disease
suberin
an inert impermeable waxy substance present in the endodermal cell walls
gamma-aminobutyric acid (GABA)
an inhibitory neurotransmitter found in some brain synapses
Seral stage/sere
an intermediate stage in the ecological succession of an ecosystem advancing towards its climax community. At each seral stage key species can be identified that change the abiotic factors, especially edaphic faors, to make it more suitable for the subsequent existance of other species
Glands
an organ that secretes a specific chemical substances for use in the body or for discharge into the surroundings
Decomposer
an organism that feeds on and breaks down dead plant or animal matter, turning organic compounds into inorganic ones (nutrients) available to photosynthetic producers in the ecosystem
invasive species
an organism that is not native to an area and has a negative effect on the economy, environment or health by competing with the native species for resources
hydrostatic pressure
an osmotic pressure of the blood that enters capillaries due to the compressions of the heart muscles
transfer (t)RNA
another form of RNA, composed of a strand of RNA folded so that an anticodon binds to a codon on mRNA in a ribosome and carries an amino acid corresponding to that codon
Anti-toxins
antibodies can bind to toxins produced by pathogens and neutralise them
Target cells
any cell/tissue that has a specific receptor for a specific hormone that initiates a change in that cell/tissue
Variation
any difference between organisms
diaphragm
arch-shaped muscle at base of lungs responsible for ventilation by contraction and relaxation, changes volume and pressure of lungs ventilating them
The Lake District National Park plants present
arctic alpine plants: purple saxifrage, specialised trees: dwarf juniper, dwarf willow, carnivorous plant: sundew
dark/anisotropic/A bands of myofibrils
areas that appear dark because of the presence of thick myosin filaments
light/isotopic/I bands of myofibrils
areas that appear light because actin and myosin filaments do not overlap
secondary colonisers
arrive as spores or seeds and the humus and eroded rocks means that new species can be supported, pioneer species may also act as a food source for secondary colonisers
Efferent arteriole
arteriole that leads away from glomerulus, it has a smaller cross-sectional area than the afferent arteriole to increase blood pressure in glomerulus
vasoconstriction
arterioles near the surface of the skin constrict, arteriovenous shunt vessel dilates, so very little blood flows through capillaries near skin, so heat is not lost through radiation
two main roles of the pancreas in the human body
as an endocrine gland: to produce hormones and release them into blood and as an exocrine gland: to produce enzymes and release them via the pancriatic duct into the deodenum
Important plant hormones
auxins, giberellins, abscisic acid (ABA), ethene
Immunity
balanced state of having adequate biological defenses to fight infection, disease, or other unwanted biological invasion, while having adequate tolerance to avoid allergy, and autoimmune diseases.
Examples of secondary succession
bare earth after a forest fire, cleared area of vegetation like felled forests
types of mutations
base point mutations and chromosomal mutations
Types of point mutations
base substitution and frameshift mutations
Hydrophyllic/hydrophobic interactions
between R groups of the same polarity in tertiary structure
Ionic bond
between charged part of different amino acid R groups
Mechanism of ADH action
binds to receptor on cell membrane of cells of collecting duct, triggers cAMP that triggers cascade of reactions to move vesicles with aquaporins to cell membrane allowing more water to be reabsorbed
Evidence for evolution provided by comparative biochemistry
biological molecules can be highly conserved over time so closely related species' biological molecules eg DNA can be compared to discover how closely they were related by a common ancestor by the rate of mutation
growth rate =
birth rate + immigration rate - death rate - emigration rate
troponin
blocks the binding sites of myosin heads on actin preventing muscle contraction
examples of positive feedback systems
blood clotting cascade: platelets release factors that attract more platelets, childbirth: child's head presses against cervix, stimulating oxytocin production, which stimulates uterus to contract etc.
internal stimuli/aspects that need to be coordinated
blood glucose concentration, internal temperature, water potential, cell pH
Examples of discontinuous variation
blood group, albinism, round and wrinkled peas
Single closed circulatory system
blood passes through the heart only once on each circuit around the whole of the blood circulation system of the animal
Double closed circulatory system
blood passes twice through the heart, circuits contain oxygenated and deoxygenated blood passing through lungs then around whole body
order of layers filtrate travels through from glomerular capillaries to collecting duct
blood plasma of glomerular capillaries -> capillary endothelium -> basement membrane -> through gaps in podocytes' pedicels -> lumen of Bowman's capsule -> proximal convoluted tubule -> descending loop of Henle -> ascending loop of Henle -> distal convoluted tubule -> collecting duct
mesenteric vein
blood vessel that carries deoxygenated blood from the small intestine, colon and rectum and feeds in to the hepatic portal vein
splenic vein
blood vessel that carries deoxygenated blood from the spleen, stomach and pancreas and feeds in to the hepatic portal vein
hepatic artery
blood vessel that delivers oxygenated blood to the liver
hepatic vein
blood vessel that removes deoxygenated blood from the liver
hepatic portal vein
blood vessel that supplies liver with blood from intestine and is loaded with products of digestion, fed into by the mesenteric vein and splenic vein
Examples of anatomical adaptations
body coverings such as hair, scales, spines, feathers, shells; camouflage to avoid predation, teeth related to diet, mimicry of a dangerous species to avoid predation
detoxification
body creates many toxins as metabolic waste products or by choice by ingesting drugs, liver detoxifies the substances making them harmless eg hydrogen peroxide -> oxygen and water as hepatocytes make enzyme catalase
Examples of a characteristic in animals that is a result of environmental variation and genetic variation
body mass, height
actin-myosin cross-bridges
bonds formed between the actin filaments and the myosin heads
Examples of ex situ conservation methods
botanic gardens, seed banks, captive breeding programmes
brochioles
branches of the bronchi feeding air deeper into lungs no cartilage
outbreeding
breeding of distantly related organisms
Methods of natural cloning in plants
bulbs, runners, rhizomes, stem tubers
quantitative measure of genetic biodiversity
calculating proportion of polymorphic gene loci
Causes of mutations
can be naturally occurring or risk can be increased by exposure to mutagens
facultative anaerobes
can do aerobic respiration when oxygen is around but can switch to anaerobic respiration in the absence of oxygen, eg yeats
obligate aerobes
can only synthesise ATP in the presence of oxygen for example mammals
obligate anaerobes
cannot survive in the presence of oxygen, neatly all are prokaryotes and some fungi
functions of the liver
carbohydrate metabolism, synthesis of plasma proteins, deamination of excess amino acids, transamination, detoxification
main metabolic products in mammals
carbon dioxide from cellular respiration excreted by lungs, bile pigments from breakdown of old rbcs excreted from liver in bile, nitrogenous waste products (urea) formed of the breakdown of excess amino acids excreted in urine
myogenic
cardiac muscles are this because they have their own intrinsic rhythm of ~60bpm
Haemodialysis
carried out by a diaysis machine where blood leaves patients artery and flows into machine, flows through partially permeable dialysis membranes which mimic basement membrane in Bowman's Capsule, urea and excess mineral ions leave by diffusion, countercurrent flow to maintain steep concentration gradients
vein
carry deoxygenated blood away from cells towards the cell, do not have a pulse, large lumen and volume, low blood pressure, contain valves to prevent backflow, run through active muscles so when they contract they make blood flow (movement of thorax in breathing also does this), >1cm
Artery
carry oxygenated blood away from heart, small lumen, lots of elastin fibres, which evens out surges of blood, blood under high pressure, around 2.5-0.4 cm
role of giberellin as a plant hormone
cause stem elongation, trigger the mobilisation of food stores in a germinating seed, stimulate pollen tube growth in fertilisation
role of ethene as a plant hormone
causes fruit ripening, promotes abscission in deciduous trees
serotonin in blood clotting
causes smooth muscles in blood vessel walls contract restricting blood flow to area
Meiosis
cell division that results in 4 genetically different haploid (n) daughter cells
senescent cells
cells with damaged DNA that are no longer viable, meaning they enter the phase of permanent cell arrest (G0)
sclereids
cells with extremely thick cell walls that support phloem vessels
Podocytes
cells with long extensions called pedicels that wrap around glomerular capillaries and act as another sieve to prevent larger components of blood to be filtered through
Electrofusion as an example of genetic engineering in plants
cellulase decomposes cell wall, then fused to form polyploid cell and stimulated with hormones to form cellulose cell wall again
sinusoids
chambers where blood from the hepatic artery and the hepatic portal veins mixes together, they are surrounded by hepatocytes, mixing increases the oxygen content of the blood from the hepatic portal vein supplying cellular respiration in hepatocytes
plant hormones/plant growth factors
chamicals produced by some plant cells that act as chemical messengers and initiate a change in a target cell, travel by diffusion, symplastic /apoplastic pathways and xylem and phloem
repolarisation
change of p.d. of axon from +40mV to -70mV
Polygenic characteristics
characteristics controlled by more than one gene
Monogenic characteristics
characteristics controlled by one gene
Sex-linked genes
characteristics determined by genes carried on the X sex chromosome and can be dominant and recessive
spindle assembly checkpoint
checks for: chromosome attachment to spindle
human chorionic gonadotrophin (hCG)
chemical produced by the developing placenta in an early embryo
Terminator bases
chemically modified DNA nucleotides that will stop DNA polymerase synthesisng DNA at that location with a coloured fluorescent tag added with a different colour for each base
neurotransmitters
chemicals
Perforin
chemicals secreted by cytotoxic T cells that create holes/pores in pathogen or infected (by virus) or cancerous cells, making them more permeable
Opsonins
chemicals that bind to pathogen antigens eg antibodies that mark pathogen so they are more easily recognised by phagocytes
neurotransmitters
chemicals that transmit nervous impulses across the synapse
palisade cells
chloroplast for photosynthesis, rectangular shape can be closely packed, thin cell wall for CO2 diffusion, Large vacoule to maintain turgor, chloroplasts can move in cytoplasm to absorb more light
Recombinant chromatids
chromatids that have different alleles due to crossing over
Prophase
chromatin fibres coil to make chromosomes, nucleolus disappears, nuclear membrane breaks down, protein microtubules form spindle fibreslinking poles moving chromosomes into correct positions, centrioles move to poles of the cell, the spindle fibres attach to centromeresand move them to centre of cell
Metaphase
chromosomes are moved by spindle fibres to create a plane in the centre of the cell
Telophase
chromosomes reach poles, a nuclear envelopes forms around each pole's chromosomes, nucleolus formed as chromosomes uncoil. Cleavage furrow made then Cytokinesis occurs
Telophase I
chromosomes reach poles, a nuclear envelopes forms around each pole's chromosomes, nucleolus formed as chromosomes uncoil. Cleavage furrow made then Cytokinesis occurs
B memory cells
circulate for decades and provide immunological memory they are programmed to remember the specific antibody for a specific antigen and enable the body to make a rapid secondary response when the same antigen is encountered again in the future
T memory cells
circulate in the blood for decades and are part of the immunological memory. The coordinate the swift response to the secondary response to an already encountered pathogen by cloning themselves
decarboxylation and dehydrogenation I of Kreb's Cycle
citric acid is oxidised by loss of H to reduce NADH (dehydrogenation) and carbon dioxide is evolved (decarboxylation), a 5C compound is made
exons
coding regions od DNA
addition of Coenzyme A of link reaction
coenzyme A adds onto the 2C acetyl group to form acetylcoenzyme A (acetyl CoA)
Vitamins are a source of...?
coenzymes
Antarctica brief description
coldest, driest, windiest and emptiest continent, mostly ice sheets, has only summer and winter
leucocytes
collective term for all white blood cells involved in immune responses
The main reasons for the increase in global atmospheric carbon dioxide levels
combustion of fossil fuels releasing trapped carbon dioxide back into the atmosphere, deforestation which means less carbon dioxide is removed from the atmosphere and in many cases cleared forest is burned which contributes even more to global atmospheric carbon dioxide levels
Cell signalling
communication between different cells by the release of chemicals, which have an effect on target cells; can be local at synapse or over larger distances, using hormones
globular proteins
compact, water soluble, and usually roughly spherical in shape
intraspecific competition
competition between individuals that belong to the same species
interspecific competition
competition between individuals that belong to two or more different species
Sterols/steroid alcohols
complex alcohol lipids 4 carbon rings and hydroxyl ending eg cholesterol
tropomyosin molecule
component of actin helically wound around it blocking actin-myosin binding sites
elastic fibres
composed of elastin and can stretch and recoil providing vessel walls with flexibility
cellular compartmentalisation
comprise all of the closed parts within the cytoplasm of a eukaryotic cell, usually surrounded by a single or double lipid layer membrane
arteriole
connect arteries to capillaries, have less elastin and collagen but more smooth muscle and control homeostasis through vasodilation and vasoconstriction, around 30 um
Cell body
contains nucleus surrounded by cytoplasm, lots of mitochondria and ER to produce neurotransmitters
properties of slow-twitch muscles
contract slowly, less powerful contractions, can keep going for longer, gain energy from aerobic respiration, rich in myoglobin so redder in colour, rich supply of blood vessels and mitochondria
properties of fast-twitch muscles
contract very quickly, produce powerful contractions only for a short period, used for short bursts of speed and power, tire easily, gain energy from aerobic respiration, pale due to less myoglobin, contain more and thicker myosin filaments, store creatine phosphate - a molecule that can rapidly generate ATP from ADP in anaerobic conditions
smooth muscle
contracts or relaxes changing the size of the lumen
Mineralocortoids
control blood pressure by maintaining the balance between salt and water concentrationsin the blood and bodily fluids
role of auxins as a plant hormone
control cell elongation, prevent leaf abscission, maintain apical dominance, involved in tropisms, stimulate the release of ethene, involved in fruit ripening
Examples of active management techniques in wildlife reserves
controlled grazing by limiting grazing areas or numbers, restricting human access, controlling poaching by creating defences/issuing fines, feeding animals to ensure they survive to reproductive age, reintroduction of species to locally extinct/decreased numbers areas, culling or removal of invasive species, halting succession
cerebrum
controls coluntary actions, such as learning, memory, personality and conscious thought
cerebellum
controls unconscious functions such as posture, balance and non-voluntary movement
sequence of events of Kreb's Cycle
conversion, formation of citric acid, decarboxylation and dehydrogenation, decarboxylation and dehydrogenation, substrate level phosphorylation, dehydrogenation, dehydrogentaion and regeneration
Cell mediated immunity
coordinated by T helper cells and activated when cells become changed
pre-mRNA
copied from original DNA, mRNA that has introns and exons
fever cause
cytokines stimulate the hypothalamus and increase body temp
Bulbs (example and explanation) as a form of natural plant cloning
daffodil, leaf bases swell with stored food from photosynthesis. Internal buds form which develop into new plants
Detritus
dead and decaying material
Ways in which agriculture affects biodiversity
deforestation to increase available land for crops/animals, removal of hedgerows to increase land area and make mechanisation easier, use of chemical pesticides and herbicides that can impact ecosystems, monoculture crops
Main human influences on biodiversity
deforestation, monoculture agriculture, climate change, pollution (chemical), littering (as the improper disposal of waste and packaging)
dehydrogenation of link reaction
dehydrogenase enzyme catalyse the dehydrogenation of pyruvate. The 2H are picked up the NAD+ that becomes reduced NADH (carries H+ to e.t.c.)
types of chromosomal mutations
deletion, duplication, translocation, inversion
Glomerulus
dense cluster of capillaries at the beginning of the nephron, the first stage of untrafiltration where blood plasma is forced out of the capillaries due to high blood pressure
Tips on a phylogenetic tree
descendant organisms (often a species)
Economic reasons for maintaining biodiversity
desertification reduces crop profits, non-sustainable use of resources means they will run out making industries collapse, species that may be potentially economically important are not discovered, biodiversity promotes tourism
T killer cells
destroy pathogens, virus infected cells or cancerous cells by secreting perforins that increase the permeability of targeted cells by making holes/pores in it
herbaceous dicots
dicots with soft tissues and a relatively short life cycle meaning they die down to the soil level at the end of the growing season
Interspecific variation
differences between organisms of different species
Intraspecific variation
differences between organisms of the same species
Genetic variation
differences in the genome of organisms
vasodilation
dilation of the arterioles near the skin's surface and constriction of the arteriovenous shunt vessels, forcing blood through capillaries near surface of skin, so loss of heat by radiation or conduction (if pressed against surface)
thermotropism
directional response to temperature
hydrotropism
directional response to water
Ways in which deforestation affects biodiversity
directly reduces the number of plants in an area, if only one species is felled it reduces the species' diversity, can disrupt whole ecosystems and reduce numbers of species that depended on the trees as a source of energy/shelter, animals are forced to migrate to other areas
B effector cells
divide to form cloned plasma cells
Reasons why micropropagation is used to produce artificial clones of a desirable plant
doesn't readily produce seeds, doesn't respond well to natural cloning, is very rare, has been GM or selectively bred with difficulty, is required to be pathogen-free by growers eg bananas, potatoes
cystic duct
duct that delivers bile from the gall bladder to the common bile duct
root pressure
due to mineral ions being actively pumped into the xylem fluid, the lower water potential sucks in water by osmosis and so causes a negative pressure that helps roots to absorb water however its not the main pressure
phosphorylation II of glycolysis
each triose phosphate is phosphorylated to triose bisphosphate
Sustainable development
economic development that meets the needs of people today, without limiting the ability of future generations to meet their needs
Pacinian corpuscle structure
end of sensory neurone is found in centre surrounded by layers of connective tissue, seperated by a layer of gel
islets of Langerhans
endocrine tissue of pancreas with Alpha and Beta cells
Ecological efficiency (equation) =
energy or biomass available after/energy or biomass available before x 100
G2 phase (second growth phase)
energy stores are increased, replicated DNA is checked for errors, cell continues to get bigger
roles of synapses
ensure a unidirectional impulse, they can allow an impulse from one neurone to be transmitted to a number of neurones at multiple synapses, a number of neurones may feed into the same synapsewith a single postsynaptic neurone
Sequence of events for link reaction
entering of pyruvate into mitochondrial matrix by active transport, decarboxylation, dehydrogenation, formation of acetylcoenzyme A
adrenylyl cyclase
enzyme present in cell membrane of liver cells that is activated and catalyses the production of the secondary messenger - CAMP that activates enzymes that increase glycogenolysis
Vmax
enzymes can only increase the rate of reaction up to this certain point: the maximum initial velocity or rate of the enzyme-catalysed reaction
intracellular enzymes
enzymes used inside cells to catalyse internal reactions
reducing the effect of hair or feathers
erector pili muscles (hair erector muscles relax) so hair and feathers lie flat on skin so do not trap insulating layer of air
raising body hair and feathers
erector pili muscles in the skin contract, pulling up hairs and feathers creating an insulating layer of air because air is a good insulator
type of neurotransmitters
excitatory and inhibitory
Expiratory reserve volume
extra amount of air you can force out of lungs over and above the normal tidal volume of inhalation
Ectopic heartbeat
extra heartbeats that are out of the normal rhythm
tissue fluid
extracellular fluid which bathes the cells of most tissues, arriving via blood capillaries and being removed via the lymphatic vessels.
Density dependent factors (as factors affecting population size)
factors that have an effect on a whole population based on its size eg lack of resources, overcrowding
Density independent factors (as factors affecting population size)
factors that have an effect on a whole population regardless of its size eg natural disasters: volcanoes, fires, earthquakes, storms
Lipids
fats and oils; biological molecules made of the elements C, H and O
lactate fermentation (in mammals) - description
fermentation that occurs in animal cells and produces lactate/lactic acid
Examples of tertiary colonisers
ferns, grasses
ultrafiltration
filtration of blood plasma out of capillaries into tissue fluid due to hydrostatic pressure
Proximal convoluted tubule
first, coiled region of tubuleafter the Bowman's capsule, found in the cortex of the kidney, actively reabsorbs substances from the filtrate eg all glucose
angiosperms
flowering plants
tracheole fluid
fluid that lines the ends of the tracheoles which limits the penetration of air for diffusion
Examples of limiting factors (for a population)
food availability, space, competition between organisms for resources, build up of toxic by-products of metabolism, disease, predation,
Methods of natural cloning in vertibrates
formation of monozygotic twins (identical twins), some female amphibians and reptiles will produce offspring when no males are available, however they are often males so are not true clones yet all genetic is conserved
Fibrous proteins
formed from long, insoluble molecules due to lots of amino acids with hydrophobic R-goups
role and location of smooth/involuntary muscles
found in the walls of hollow vessels, responsible for peristalsis and mechanical digestion
role and location of cardiac muscles
found only in the heart, are myogenic, responsible for contraction of cardiac vessels
platelets
fragments of large cells called megakaryocytes found in red bone marrow
strength of stimulus is proportional to
frequency of action potential impulses transmitted
Cleavage furrow
furrow creates as animal cell divide when cytoskeleton pulls in membrane
Nodes of Ranvier
gaps of around 2-3μm between Schwann cells, allowing an electrical impulse to 'jump' along an axon quicker
transcriptional (as a way in which genes are regulated)
genes can be turned on or off
polymorphic genes
genes that have more than one allele for example humans have polymorphic immunoglobulin genes that determine blood types
monomorphic genes
genes that only have one allele which ensures that basic structures of individuals within a species remains constant
Techniques that are included under synthetic biology
genetic engineering, industrial uses of, or parts of biological systems eg immobilised enzymes, the synthesis of new genes to replace faulty genes, the synthesis of an entire new organism
why does fetal Hb have a higher affinity for oxygen than adult hemoglobin?
gets blood from mother through placenta/uterus and passes close to deoxygenated blood, pO2 in placenta is low, maintains a steep diffusion gradient
conjugated proteins
globular proteins that contain a prosthetic group
phosphorylation I of glycolysis
glucose is biphosphorylated by 2 ATP molecules to hexose bisphosphate
Net production (equation) =
gross production - respiratory losses
phototropins
group of photoreceptors primarily responsible for triggering phototropisms
vascular bundles
groupings of xylem and phloem in the vascular system of plants
producers
harness high energy radiation from the sun in photosynthesis to produce organic molecules in an endothermic reaction. Also respire and create heat
fetal Hb
has a higher % saturation of Hb with O2 at same pO2 than mother meaning fetal hb has a higher affinity to O2
hypertonic solution
has a higher concentration (lower water potential) than the inside of the cell. Water leaves the cell, causing shrinking and shriveling.
hypotonic solution
has a lower concentration (higher water potential) than the inside of the cell. Water enters the cell and it swells and bursts.
structure of the liver
has many lobes, made of simple cells that are uniform in apperance
isotonic solution
has the same concentration (water potential) as the inside of the cell. Water leaves and enters the cell at equal rates.
Characteristics of Bacteria as a domain of (Woese's) Three Domain System of classification
have 70s ribosomes, RNA polymerase containd 5 proteins
Characteristics of Archae as a domain of (Woese's) Three Domain System of classification
have 70s ribosomes, RNA polymerase contains 8-10 proteins and is very similar to eukaryotic ribosome
Characteristics of Eukarya as a domain of (Woese's) Three Domain System of classification
have 80s ribosomes, RNA poymerase contains 12 proteins
Adaptations of cells lining proximal convoluted tubule
have microvilli, increasing SA for reabsorption. Have lots of mitochondria to provide ATP for active transport
cilliated cell
have rhythmically moving cilia that move mucus
anti-inflammatory
having the effect of retarding or inhibiting inflammation
anti-coagulant
having the effect of retarding or inhibiting the coagulation of the blood.
possible uses of stem cells
heart disease, type 1 diabetes, Parkinson's disease, Alzheimer's disease, macular degeneration, birth defects, spinal injuries
carbohydrate metabolism
hepatocytes involved in the homeostatic control of blood glucose concentration, convert gucose to glycogen under the influence of insulin and convert glycogen into glucose under the influence of glucagon
lysis of glycolysis
hexose bisphosphate breaks into two molecules of triose phosphate
Evidence for evolution provided by comparative anatomy
homologous structures as evidence for divergent evolution from a common ancestor where the superficial anatomy is the same but with a different set of adaptive features which shows the 2 species changed genetically over time
erythropoietin
hormone produced by the kidneys that stimulates the formation of rbc's
external stimuli/aspects that need to be coordinated
humidity, external temperature, light intensity, new or sudden sound
Types of migration
immigration, emigration
Disadvantages of using immobilised enzymes
immobilisation process may reduce efficiency, higher initial cost of materials but do not need to be replaced frequently, higher initial cost of bioreactor, more technical issues due to higher complexity of process
Natural passive immunity
immunity gained by the antibodies that circulate in the mother's blood and to the baby through the placenta and those found in colostrum, which gives immunity to pathogens in mother's immediate environment
Natural active immunity
immunity gained by the specific immune system where memory cells have antibodies on their surface specific and complementary to antigens of pathogens already encountered
Natural immunity
immunity that is present without prior immunization.
bivalent
in Prophase I when homologous pair of chromosomes pair up in the nuclues
The Hardy-Weinberg principle
in a stable population with no disturbing factors, the allele frequencies will remain constant from one generation to the next and there will be no evolution
Peritoneal dialysis
in body, uses natural dialysis membrane in lining of abdomen - peritoneum, catheter inserted into abdomen and urea and excess mineral ions can leave through membrane and into dialysis fluid
Plasmolysis
in plant cells when the surrounding area has a lower water potential, so water leaves the cell and the protoplast is pulled away from the cell wall
2 main categories of conservatio
in situ conservation and ex situ conservation
Environmental factors causing chlorosis in plants
in the absence of light plants will turn off their chlorophyll production to conserve resources, mineral deficiencies of iron and magnesium, viral infections that affect the metabolism of cells
Precursor enzymes
inactive enzymes that need to undergo a change in their tertiary structure, particularly active site to be activated
zymogen/proenzyme
inactive precursor enzymes that need a biochemical change eg pH or temperature to change it's active site tertiary structure
how is glomerular filtrate measured?
indirectly by a blood test that measures creatinine levels which help to give an estimated glomerular filtrate rate (eGMR)
Carriers
individuals that are heterozygous for a recessive condition so carry the faulty alleles but they are healthy bacause of the healthy dominant allele
the most common natural auxin
indoleactic acid (IAA)
transverse (T) tubules
inner foldings of the sarcolemna that help to spread nervous impulses throughout the sarcoplasm
types of frameshift mutations
insertion and deletion
Beta pleated sheets
interactions between the amino acid repeating structure form hydrogen bonds and make the flat, sheet-like structures (R groups not involved
Alpha helices
interactions between the amino acid repeating structure form hydrogen bonds and make the structure coil (R groups not involved)
2 main types of competition
interspecific compeition and intraspecific competition
sodium potassium pump
intrinsic transport protein in neurones actively pumps 2Na+ out of axon and 3K+ into axon, important in creation of resting potential, always active, energy comes from hydrolysis of ATP
Units for energy in a tropic level and why are they used in this way?
kJm^-2yr^-1 ( to allow for seasonal changes in photosynthetic production and consumer feeding patterns throughout year)
Units of biomass
kgm^-2 for an area of land and kgm^-3 for a volume of water or air of variable depth
Causes of kidney failure
kidney infection that damages or destroys podocytes or tubules, raised blood pressure can damage epithelial cells and basement membrane of Bowman's capsule, genetic conditions such as polycystic kidney disease where fluid-filled cysts can put pressure on structures and damage them
Vaccines can contain:
killed or inactive bacteria or viruses, attenuated strains of bacteria and viruses, toxin molecules altered and detoxified, isolated antigens from pathogen, genetically engineered antigens
haemoglobin structure
large, globular conjugated protein made of four polypeptide chains, each with an iron-containing haem group
xylem
largely non-living tissue that transports water and mineral ions, and support. The direction of flow of mineral ions is from roots to shoots and leaves.
liver
largest internal organ has major role in homeostasis, has a rich blood supply
Pelvis
latin for basin is the central chamber where the urine collects before passing down the ureter
leaf abscission
leaf fall from deciduous trees
Examples of continuous vartiation
leaf surface area, animal body mass, skin colour
β cells
less numerous, smaller in size , synthesise and release insulin
Management techniques used in many environmentally sensitive areas
limiting the areas tourists can visit, controlling the movement of livestock, introducing anti-poaching measures, replanting of forests and native plants, limiting hunting through quotas and seasonal bans
venule
link capillaries to veins, have very thin walls mostly of collagen, around 1mm
oils
lipids that are generally liquid at RTP
Fats
lipids that are generally solid at RTP
Common features of a circulatory system
liquid transport medium, vessels that carry the medium, a pumping mechanism
hepatocytes
liver cells; have large nuclei, prominent Golgi apparatus and lots of mitochondria, secrete bile from brakdwn of blood
Biotic limiting factors (definition and examples)
living limiting factors eg predation, disease, competition
phloem
living tissue that transports food in the form of organic solutes around the plant from the leaves where they are made by photosynthesis. Supplies cells with sugar for respiration and amino acids for protein synthesis. Flow of material can go up and down
myofibrils
long cylindrical organelles made of protein, specialised for contraction, that make up the muscle fibres. They are lined up in parallel and made of actin and myosin
Pedicels
long extensions of podocytes that wrap around capillaries of glomerulus and act as a third sieve
Fatty acids
long lipid chains with a carboxyl (-COOH) group at one end
sieve tube elements
long, hollow main transport vessel of phloem in between sieve plates
euchromatin
loosely wound DNA present during interphase
symptoms of complete kidney failure
loss of electrolyte balance K, Cl and Na cannot be excreted so osmotic balances kill tissues, build up of toxic urea, high blood pressure, weakened bones as the Ca/P balance lost, pain and stiffness in joints, anaemia kidneys produce erythropoietin
Reasons why organisms born in captivity may not be suitable for release in to the wild
loss of resistance to local or wild diseases, captive animals may not have learnt behaviours through copying or experience due to domestication, genetic incompatibility of captive organisms may mean they cannot interbreed, if habitat is too small it cannot support any more individuals leading to competition and fighting for territory
Chlorosis (as an example of a characteristic in plants that is a result of environmental variation and genetic variation)
loss of the normal green coloration of leaves of plants, caused by iron deficiency in lime-rich soils, disease, or lack of light.
post-transcriptional (as a way in which genes are regulated)
mRNA can be modified which regulates translation and the types of proteins produced
chromatin remodelling (as an example of transcriptional gene regulation)
mRNA cannot be synthesised during cell division because condensed into heterochromatin so that RNA polymerase cannot access the genes but can be accesed during interphase when DNA as euchromatin, also prevents energy-consuming proteins synthesis occurring during cell division
Isolation of the desired gene in genetic engineering if the locus of the gene is not known
mRNA extracted from a somatic cell that produces the desired product. mRNA treated with reverse transcriptase to make complementary DNA, cDNA
structure of actin
made of 2 actin filaments (made of actin subunits) spiralled around with tropomyosin and troponin blocking actin-myosin binding sites for myosin heads
structure of myosin
made of an hinged head (allowing it to move back and forwards) with a binding site for actin and ATP and a tail
muscle fibres
made of bundles of myofibrils make up skeletal muscles
Triglycerides
made of glycerol and three fatty acids in a triple condensation reaction connected by ester bonds
quarternary structure of proteins
made of many polypeptide chains (units) and inorganic prosthetic groups
Adenosine triphosphate (ATP)
made of the purine nitrogenous base adenine, pentose sugar ribose and three phosphate groups
thermoregulation
maintainance of a constant core body temperature to maintain optimum enzyme activity
role of abcsisic acid (ABA) as a plant hormone
maintains dormancy of seeds and buds, stimulates cold protective responses like antifreeze production, stimulates stomatal closing
Benefits of in situ conservation
maintains the genetic diversity of species and evolutionary adaptations that enable a species to adapt to changing environmental conditions such as climate or pest populations, preserves interdependent species in ecosystem, generally cheaper
histamines in inflammatory response
make the blood vessels dilate, causing localised heat and redness, which helps prevent pathogens from reproducing. Make blood vessels walls more leaky and blood plasma leaks out causing swelling.
role and location of skeletal muscles
make up most of body bulk and are responsible for movement of the body, commonly connected to bones by tendons and make them move
spermatazoa
male gamete, flagellum for movement, mitochondria for ATP/energy prod for movement, acrosome with digestive enzymes breaks down ovum
Antarctica animals present
mammals in surrounding seas: whales, seas, (Emperor) penguins, wingless midge only invertibrate
The Galapagos Islands plants present
mangroves in coasts - salt-tolerant, cacti in arid zones - drought-tolerant, cloud forests in humid zones with many mosses
Bioremediation using natural organisms
many microorganisms naturally beak down organic material producing carbon dioxide and water. Naturally occurring microorganisms can be supported (by adding specific nutrients to the surroundings) can neutralise many organic contaminants eg crude oil spills
Rhizomes (example and explanation) as a form of natural plant cloning
marram grass. Specialised horizontal stem running underground, often swollen with food. Buds develop, forming vertical shoots that develop independently
Inspiratory reserve volume
maximum volume of air you can breathe in over and above normal inhalation
Sampling bias
may affect reliability of a selection process accidentally or deliberately
main types of sensory receptors
mechanoreceptors, chemoreceptors, thermoreceptors, photoreceptors
Ways in which continued global warming will affect biodiversity
melting of polar ice caps could lead to the extinction of plant and animal species found there due to loss of habitat, rising sea levels will reduce the available terrestrial habitats and salt water will flow further up rivers decreasing fresh water habitats, higher temps and less rain will result in the death of some species, leading to xerophytes becoming more dominant, disrupting ecosystems, change in insect life cycles and populations changing pollination affecting plants and spreading tropical diseases towards poles
Roles of lipids
membrane formation, hormone production, thermal insulation, bouyancy, electrical insulation of electrical impulse, waterproofing, cushioning to protect vital organs, chemical energy store,
capillary
microscopic blood vessels that link arterioles and blood vessels, that form beds/networks, lumen small enough for one rbc around 10um, most have large gaps between endothelium cells so that substances can be easily exchanged, only one cell thick
Phospholipid
modified triglycerides containing the elements C, H, O and P, made of glycerol ester bonded to two fatty acids tails and an inorganic phosphate ion head. Head is hydrophillic and tails are hydrophobic
amino acid
monomers for the production of proteins, they all have a similar structure but different R groups
hexose monosaccharides
monosaccharides with a 6 atom ringed structure
pentose monosaccharide
monosaccharides with a 6 atom ringed structure
α cells
more numerous, larger in size, synthesise and secrete glucagon
Examples of secondary colonisers
mosses, hardy plants
Factors affecting genetic biodiversity
mutations in the DNA of an organism, creating new alleles and interbreeding between different populations - gene flow
silent mutations
mutations that cause a change in the codon but it still codes for the same amino acid because it is degenerate or if it occurs in a non-coding region
factors affecting action potential travel speed
myelination, axon diameter (bigger diameter means less resistance to ions in axon and bigger surface area for Na+ influx), temperature
The results of a muscle contraction
myosin filaments pulll the actin filaments inwards towards the centre of the sarcomere and the light band becomes narrower, the Z-lines move closer together, shortening the sarcomere, the H-zone become narrower
nasties
nastic movements
presynaptic neurone
nerone along which the impulse has arrived to the synapse from
Ways of controlling heart rate
nervous (by chemoreceptors and baroreceptors), hormonal (adrenaline and noradrenaline)
area of production of ADH
neurones in the hypothalamus
myelinated neurones
neurones who's axons are covered in a myelin sheath, insulating them and increasing the speed of their electrical impulse transmission
Effects of different mutations
neutral, damaging/harmful, beneficial
neutral (as an effect of a mutation)
no effect on the phenotype of an organism because normally functioning proteins are still synthesised
Extinct
no organisms of the species exist anywhere in the world
introns
non-coding regions of DNA
nastic movements
non-directional plant responses
chemonasty
non-directional response to chemicals
photonasty
non-directional response to light
thermonasty
non-directional response to temperature
thigmonasty
non-directional response to touch
hydronasty
non-directional response to water
Abiotic limiting factors (definition and examples)
non-living limiting factors eg temperature, pH, light, water availability, oxygen availability, humidity
types of effects of mutations
nonsense, missense, silent
breathing rate
number of breaths taken per minute
proportion of polymorphic gene loci (equation)=
number of polymorphic gene loci/total number of loci x100%
Recombination frequency (equation) =
number of recombinant offspring/total number of offspring x 100
saltatory conduction
occurs in myelinated neurones where Na+ ions can only enter at the Nodes of Ranvier, loacalised circuits are set up so the action potential can 'jump' from one node to the next, which is more energy efficient than repoolarisation of whole axon
Evidence for evolution provided by paleontology
oldest rocks contain simplest organisms and recent rocks have more complex organisms, the sequence in which organisms are found matches their ecological links (animals need plants so come after them in time), comparative anatomy of fossils can show common ancestors and divergent evolution to today's organisms, fossils can show relationship between living and extinct species
Cascade effect (of adrenaline action)
one molecule of adrenaline creates 2 cAMP molecules and each activates 4 enzymes so 8 in total, each stage has more activation that the one before
Allele
one of the possible forms of a gene
monocotyledonous plants
one of the two main groups of flowering plants that have 1 embryonic leaves (cotyledons)
dicotyledonous plants (dicots)
one of the two main groups of flowering plants that have 2 embryonic leaves (cotyledons)
Antarctica plants present
only grow in sheltered ice-free areas: lichen, mosses, algae
How are organisms classified?
organisms are separated into the 3 domains, then down the taxonomical hierarchy where the number of organisms in each group decreases but their similarities increase
Why is coordination needed?
organisms need to coordinate the functions and of different cells and systems to operate effectively
Extinct in the wild
organisms of the species only exist in captivity
Saprotrophs
organisms that obtain energy by saprobiotic nutrition - from dead or waste waste organic material
Detritivores
organisms that speed up decomposition by feeding on detritus, breaking it down into smaller pieces of organic material, which increases the surface area for the decomposers to work on by internal digestion
perennating organs
organs in plants that contain stored food from photosynthesis and can remain dormant in soil. Are a means of asexual reproduction, natural cloning and survival in adverse conditions
cotyledons
organs that act as food stores for the developing embryo plant and form the first leaves when the seed germinates
Factors affecting enzyme action
pH, temperature
sympathetic nervous/motor system, SMS
part of the ANS, regulates the body's 'flight or fight' responses as well as homeostasis (neurotransmitter noradrenaline)
parasympathetic nervous/motor system, PSNS
part of the ANS, responsible for the body's relaxing responses like 'feed and breed' and 'rest and digest'
somatic/voluntary nervous system, SoNS
part of the PNS that is under conscious control eg voluntary skeletal muscular movements (neurotransmitter acetylcholine)
autonomic nervous system, ANS
part of the PNS that works constantly under subconscious control (involuntary) eg life-sustaining mechanisms like breathing
Examples of uses of immobilised enzymes
penicillin acylase used to make semi-synthetic penicillin from natural penicillin making it more effective, glucose isomerase used to make sweeter fructose from glucose, lactase to make lactose free milk, blucoamylase used to break down starch to glucose (syrup), nitrile hydratase used to plastics from acrylamide
Prosthetic group
permanent non-protein component binded to the polypeptide chain by Hydrogen bonds eg Fe(II) in heam
ascending limb of Loop of Henle role in countercurrent multiplier effect
permeable to NaCl, impermeable to water, NaCl moves out by diffusion down electrochemical gradient into medulla, at end filtrate is isotonic
collecting duct role in countercurrent multiplier effect
permeable to water as controlled by ADH as water potential of medulla is very concentrated so water moves out due to osmosis and leaves very concentrated urine
descending limb of Loop of Henle role in countercurrent multiplier effect
permeable to water, impermeable to NaCl, isotonic to blood, water moves out by osmosis then back into capillaries
Uses of SCNT
pharming by SNCT a cow can be GM to produce human proteins in its milk
damaging/harmful (as an effect of a mutation)
phenotype of the organism is affected in a negative way because proteins are no longer synthesised or synthesised proteins are non-functional
photosynthetic pigments
pigments that absorb light, release excited electrons, used in light-dependent stage of photosythesis, found in photosystems
metaphase plane/plate (equator)
plane created by chromosomes being moved to centre by spindle fibres in metaphase
hydrophytes
plants adapted to living in in water (fully or partially submerged) or soil permanently saturated with water
xerophytes
plants adapted to very low (soil-)water availability eg cacti, succulents, conifers and marram grass
perennial plants
plants that live longer than 2 years
hyperaccumulates
plants which can take up large amounts of metals from the ground
sieve plates
plates formed at the walls of adjoining cells in phloem with pores to allow phloem contents to flow through
Nodes on a phylogenetic tree
points of divergent evolution from a common ancestor
Examples of physiological adaptations
poison production to kill prey or protect themselves from predation, antibiotic production to kill competing bacteria, water holding like cacti
order of nervous impulse transmission
polarised, depolarisation, repolarisation, hyperpolarisation, polarised
Snowdonia National Park and The Lake District National Park problems caused by human activities
popular tourist destination: footpath and soil erosion, trampling, litter, disruption of wildlife
Stem tubers (example and explanation) as a form of natural plant cloning
potato. Tip of an underground stem becomes swollen with stored food to form a tuber or storage organ. Buds on the storage organ develop producing new shoots
The aims of sustainability are to:
preserve the environment, ensure resources are available for future generations, allow humans in all societies to live comfortably, enable LEDC's to develop by exploiting their natural resources , create a more even balance in the consumption of these resources between MEDC's and LEDC's
turgor pressure/hydrostatic pressure
pressure caused by water being confined to a small space as in plant cell that aids support and root cell expansion
Penecillin production production info
process uses relatively small fermenters because its very hard to maintain high levels of oxygen in large bioreactors, mixture continuously stirred to keep it oxygenated, grown in rich nutrient medium, buffer added to nutrient medium maintaining pH at ~6.5, temp constant at ~25-27'C
bioprocesses
processes utilising biotechnology
Schwann cells
produce layers of membrane by growing around the axon many times
Plasma cells
produce speciifc antibodies to an antigen and release them in to circulation
Arguments against micropropagation
produces a monoculture, so all plants are susceptible to same diseases or changes in environment, relatively expensive process, needs skilled workers, explants and plantlets vulnerable to (fungal) infections, if initial sample has viral infection so do all clones, large numbers of plants may be lost during the process
assimilates
products of photosynthesis that are transported by translocation
the magnitude of the force that is exerted by a muscle is
proportional to the number of motor units stimulated
meninges
protective membranes around the brain
symptoms caused by infected kidneys or if they are affected by high blood pressure
protein in urine - lack of filtration if podocytes and b.m. damages, blood in urine
Results of a mutation
protein synthesis can be disrupted if mutation within a gene/coding region
post-translational (as a way in which genes are regulated)
proteins can be modified after synthesis which changes their function
G1 phase (first growth phase)
proteins produced to make organelles, organelles replicate, cell gets bigger
channel protein
provide a hydrophyllic channel that facilitates passive processes (diffusion) of polar molecules or ions down a concentration gradient.
Collagen
provides structural support to maintain the shape and volume of the vessel
Open circulatory system
pump blood into a hemocoel with the blood diffusing back to the circulatory system between cells
lactate fermentation explanation
pyruvate accepts H from reduced NAD, catalysed by lactate dehydrogenase to produce lactate
alcoholic fermentation (in yeast and many plants) - description
pyruvate is converted to ethanol by yeast and in many waterlogged plant roots
alcoholic fermentation (in yeast and many plants) - explanation
pyruvate is decarboxylated by pyruvate decarboxylase and CO2 is released to make ethanal which is hydrogenated by accepting H from reduced NAD oxidising it
shivering
rapid, involuntary contraction and relaxation of the large voluntary muscle in the body, heat from the metabolic exothermic reactions raises core body temp
pancreatic acini
raspberry-shaped clusters of exocrine cells in pancreas that secrete enzymes into branches of the pancreatic duct
Osmoreceptors
receptor cells in the hypothalamus that are sensitive to the concentration of inorganic ions in the blood (do so by detecting a change in their volume) and are linked to the release of ADH
positive feedback
receptor detects change, processed and an effector reinforces the change to cause an exponential response to an initial stimulus
neurotransmitter receptors
receptor molecules which the neurotransmitter binds to in the postsynaptic membrane
negative feedback system
receptors detect change, processed and an effector counteracts the detected change
hypothalamus
regulatory centre for temperature and water balance
goblet cell
release mucus to catch pathogens and dust
decarboxylation
removal of a carbon from a compound usually in the form of CO2
dephosphorylation
removal of a phosphate group
dehydrogenation
removal of hydrogen from a molecule
excretion
removal of metabolic (from bodily chemical reactions) waste products from the body, passes through a membrane so was 'inside' the body
Kidney gross structure components
renal artery, renal vein, cortex, medulla, pelvis, ureter
Thymine in mRNA
replaced with Uracil and binds to Adenine
Kupffer cells
resident macrophages of the liver, ingest foreign particles and pathogens
Humoral immunity
response of B cells to pathogens outside of cells eg bacteria and fungi
excitatory neurotransmitters
result in the depolarisation of the postsynaptic neurone, by triggering the threshold voltage and releasing an action potential, eg acetylcholine
inhibitory neurotransmtter
result in the hyperpolarisation of the postsynaptic membrane, preventing an action potential being triggered eg gamma-aminobutyric acid
Ascending loop of Henle
runs back up from the medulla to the cortex
Descending loop of Henle
runs down from the cortex to the medulla to a hairpin bend at the bottom
Bioremediation using GM organisms
scientists are trying to develop Gm bacteria that can break down or accumulate contaminants which they would not naturally do eg bacteria have been GM to remove mercury contamination from water
duplication (as a type of chromosomal mutation)
sections of a chromosome get copied
Factors decreasing genetic biodiversity
selective breeding/artificial selection, captive breeding programmes, rare historically selectively bred breeds of domestic animals, artificial clones (cuttings), natural selection, genetic bottlenecking, founder effect, genetic drift
dendrons
short extensions that come from cell body, divide into smaller extensions called dendrites. Responsible for transmitting electrical impulses towards the cell body
Most populations have this type of growth curve
sigmoid growth curve
axons
singular, elongated nerve fibres that transmit impulse away from cell body, cylindrical, very narrow cytoplasm surrounded by plasma membrane
actin-myosin binding sites
sites on actin molecules where myosin heads form actin-myosin cross-bridges with the actin filament
Ways of measuring populations
size, density, growth rate
types of muscles
skeletal, cardiac, involuntary/smooth muscles
current uses of stem cells
skin grafting as burn treatment, drugs trialed are done so on cultures of stem cells before human or animal testing, developmental biology e.g. embryology etc.
Types of muscle fibres
slow-twitch and fast twitch muscle fibres
spiracles
small opening on insects' located on abdomen and thorax for gaseous exchange
alveoli
small pockets that are the respiratory functional units of the lungs with a rich blood supply, only single epithelial cell thick, covered in lung surfactant
lymph node
small swellings in the lymphatic system where lymph is filtered and lymphocytes are formed.
dendrites
smaller extensions that divide from dendrons. Responsible for transmitting electrical impulses towards the cell body
neurones
specialised nerve cells that transmit electrical impulses from around the body
Aerenchyma
specialised parenchyma cells that take part in apoptosis to produce air spaces
phagocytes
specialised white blood cells that engulf and destroy pathogens
voltage gated ion channels, VGIC's
specific ion channel proteins that only change shape when a threshold voltage is reached
Pacinian corpuscle function and location
specific sensory receptors that detect mechanical pressure, located deep in skin, feet and are responsible for joint proprioception
Anaphase
spindles attach to CENTROMERE, CENTROMERE splits, sister chromatids pulled to opposite poles as spindles shorten, CENTROMERE leading, detachement of spindle fibres
Natural plant cloning/propagation methods used in horticulture
splitting bulbs, removing young runners, cutting up rhizomes, taking cuttings from short sections of stems
Haematopoietic cells
stem cells in the bone marrow that can differentiate into all the blood cells
guard cells (pairs)
stomata for CO2 to enter plant for photosynthesis, close when they have low water level to prevent excess transpiration
pituitary gland
stores and releases hormones that regulate many bodily functions
Runners (example and explanation) as a form of natural plant cloning
strawberry, spider plant, Lateral stem grows away from parent and develops roosts when the runner touches the ground. Runner stem eventually withers leaving new independent individual
analagous structures
structures in different organisms that have adapted to perform the same function but are superficially different and have a different genetic origin
photoreceptors
structures or pigments that are sensitive to specific wavelengths of light (mostly blue)
Surfactents (surface active agents)
substances that reduce the surface tension of a liquid, sit at surface or boundary between water and oil, the hydrophobic end points to oil or out of water, hydrophillic end points to water. Used in pulmonary surfactent .
the symplast route of translocation
sucrose moves from mesophyll cells to companion cells by diffusion through plasmodesmata and into phloem by diffusion. Largely passive. Water moves in due to osmosis and creates a pressure that moves assimilates through phloem by mass flow
the apoplast route of translocation
sucrose travels through apoplast route by diffusion. In companion cells sucrose is actively transported into the cytoplasm by proton pumps and H+ ions acting as co-transporters for sucrose via co-transporter protein. Sucrose moves into phloem through plasmodesmata from phloem by diffusion
Stem cuttings (example and explanation) as a form of propagation
sugar cane, banana, tea and coffee bushes, pelargoniums, cacti. short sections of stems are taken and planted either directly into the ground or in pots. Rooting powder added to base of cutting to decrease time needed for rooting
total lung capacity
sum of the vital capacity and residual volume
T regulatory cells
suppress the immune system acting to control and regulate it. They stop the immune response once the pathogen has been eliminated and make sure the the body recognises self antigens. INTERLEUKINS are important in this control
Examples of behavioural adaptations
survival behaviours to increase chance of survival, courtship increases chance of reproduction, seasonal behaviours allow organisms to cope with seasonal changes: migration to more favourable environments, hibernation a period of inactivity to conserve energy, innate/instinct behaviour inherited through genes, learned behaviour from experience or observation
decreased sweating
sweat production will stop entirely so no heat energy is lost through evaporation, however some evaporation occurs from lung surfactant
increased sweating
sweat spreads out across the surface of the skin, due to water's high specific heat capacity and latent heat of vaporisation a lot of energy is needed to increase its temperature and make it evaporate meaning excess heat can be easily released this way
Ψ
symbol (psy) used to denote the water potential of a substance, which is always negative except for pure water (0kPa), measured in kPa.
cholinergic synapses
synapses that use the neurotransmitter acetylcholine, common in the CNS of vertebrates and at neuromuscular junctions
Kreb's Cycle
takes place in the mitochondrial matrix and each cycle results in the breakdown of an acetyl group
dehydrogenation and formation of ATP of glycolysis
the 2 phosphate groups of each triose bisphosphate are used to produce 2 molecules of ATP by substrate level phosphorylation. Hydrogen is also taken from the triose bisphosphate which is accepted by NAD+ to form reduced NADH which transports the H to the e.t.c.
Decarboxylation of link reaction
the 3C compound pyruvate gets decarboxylated and CO2 is released
dehydrogenation and regenaration of Kreb's Cycle
the 4C compound is dehydrogenated again by the reduction of NAD to reduced NADH, oxaloacetate is regenerated
dehydrogenation I of Kreb's Cycle
the 4C compound is dehydrogenated by the reduction of FAD to FADH2
decarboxylation and dehydrogenation II of Kreb's Cycle
the 5C compound is dehydrogenated by reducing NAD and decarboxylated by evolution of CO2, a 4C compound is made
Turgor/turgidity
the ability of the cell wall of a plant cell to exert pressure on the water and experience from the water on it
egestion
the act or process of voiding or discharging undigested food as faeces, it does not cross any membranes but stays 'outside' the body
Glycolysis
the anaerobic process that occurs in the cytoplasm of cells and involves the breakdown of glucose into pyruvate, creating ATP and reduced NAD too.
template strand
the antisense strand acts as a template strand during transcription, so that the complementary mRNA strand forms a direct copy of the base sequences as the sense strand
Biotechnology
the application of biological organisms or enzymes to the synthesis, breakdown, or transformation of materials in the service of people
Biotechnology
the application of biological organisms or enzymes to the synthesis, breakdown, or transformation of materials in the service of people on an industrial scale
Afferent arteriole
the arteriole that leads to the glomerulus, it has a greater cross-sectional area than the efferent arteriole to increase blood pressure in glomerulus
anterior pituitary gland
the back part of the pituitaryland
Exocrine system
the bodily system made up of exocrine glands that are made of epithelial cells that secrete chemicals into ducts
Peptide bond
the bond between two amino acids formed in a condensation reaction -CON-
skull
the bone capsule that houses the brain
apoplast
the cell walls and intracellular spaces between plant cells
tropisms
the change in an organism (plant) in response to a certain stimulus
action potential
the change in electrical potential associated with the passage of an impulse along the membrane of a muscle cell or nerve cell.
Decomposition
the chemical process in which a compound is broken down into smaller molecules, or into its constituent elements
Precision
the closeness of agreement between independent measurements obtained under the same conditions and depends only on the spread of measurements/distribution of random errors and does not relate to the true/accepted value
ecosystem
the community and its abiotic environment
central nervous system, CNS
the complex of nerve tissues that controls the activities of the body. In vertebrates it comprises the brain and spinal cord.
electrochemical gradient
the concentration gradient of ions influenced by their concentration and net/relative charges in different areas
symplast
the continuous cytoplasm of the living plant cells that is connected through the plasmodesmata
transamination
the conversion of one amino acid into another (important if diet doesn't contain required balance of amino acids)
Bowman's capsule
the cup-shaped structure that contains the glomerulus and it collects filtrate and passes it to the proximal convoluted tubule
Cortex
the dark outer layer of the kidneys, has a very dense capillary network carrying blood from renal artery to the nephrons, it is where blood filtration takes place
Biodata
the data obtained from various quantitative biological tests
Reliability
the degree to which an assessment tool produces stable and consistent results.
genetic engineering
the deliberate modification of the characteristics of an organism by manipulating its genetic material.
Synthetic biology
the design and construction of novel artificial biological pathways, organisms or devices, or the redesign of existing natural biological systems.
DNA profile
the developed product from the process of DNA profiling - a unique pattern of bars
Zonation
the distribution of organisms into specific zones according to such parameters as altitude or depth, each characterized by its dominant species.
Mitosis
the division of a diploid into two genetically identical cells, genetically identical also to parent
Clonal expansion
the division of activated B cells to become plasma cells and B memory cells
respiratory losses
the energy lost at each trophic level due to the nature of respiratory reactions
Nitrogenase
the enzyme present in nitrogen fixing bacteria that uses atmospheric nitrogen and hydrogen as substrates to produce ammonia
root hair cells
the exchange surface in plants where water is taken into the body of the plant from the soil
extrasystole
the extra heartbeat of an ectopic heartbeat followed by a pause
Plagioclimax
the final seral stage of an ecological ecosystem that is stopped artificially
Primary community
the first seral stage of an primary ecological succession characterised by the colonisation of a bare area by pioneering species/colonisers
Oxidative decarboxylation/link reaction
the first step of aerobic respiration that links glycolysis and Kreb's Cycle. Occurs in mitochondrial matrix
Locus of a gene
the fixed location of a gene on a chromosome
apoplastic pathway
the flow of water from root hair cells to the xylem through the apoplast due to cohesive forces in the water pulling it along
symplastic pathway
the flow of water through the symplast from root hair cells to xylem because of the change in water potential between adjacent cells moving water along by osmosis
tissue fluid
the fluid that fills the space between cells is called tissue fluid and has same composition as blood plasma but without rbc's and plasma proteins
substrate level phosphorylation
the formation of ATP without the involvement of an electron transport chain
posterioir pituitary gland
the front part of the piruitary gland where ADH is stored and then released from
Nephron
the function unit of the kidney
synaptic cleft
the gap, which seperates the axon of one neurone and the dendrite of the next, appr. 20-30 nm
pCO2 (partial pressure of carbon dioxide)
the hypothetical pressure of CO2 if it alone occupied the volume of the mixture at the same temperature
pO2 (partial pressure of oxygen)
the hypothetical pressure of O2 if it alone occupied the volume of the mixture at the same temperature
bidirectional/multidirection
the idea that translocation of assimilates in phloem can go up or down
Secondary immune response
the immune response to a secondary exposure of a pathogen with antigen already encountered, so memory cells can differentiate quickly into plasma cells and fight off the infection much quicker by producing the same specific antibodies as it did the previous time
Artificial active immunity
the immune system of the body is stimulated to make it's own antibodies to a safe form of an antigen (a vaccine), which is injected into the bloodstream (vaccination)
Primary immune response
the initial production of antibodies by plasma cells specific to a new pathogen's antibodies and takes days or even weeks
synapse
the junction between two neurones or a neurone and an effector
endodermis
the layer of cells surrounding the vascular plant tissues (xylem and phloem)
Basement membrane
the layer of collagen fibres and other proteins inside Bowman's capsule that filtrate needs to go through, acts as a sieve
H-zone
the lighter coloured region found in the centre of each dark band.. Myosin fibres are only present here and it shortens when the sarcomere contracts
Medulla
the lighter inner part of the kidney, contains the tubules of the nephrons that form the pyramids and the collecting ducts
Z-line
the line at the centre of each light band
depurination
the loss of a purine base; adenine or guanine
depyrimidation
the loss of a pyrimidine base; cytosine or thymine
homeostasis
the maintenance of a relatively constant internal environment
Conservation
the maintenance of biodiversity through human action or management which includes maintaining diversity between species, maintaining diversity within a species and the maintenance of habitats
Osmoregulation
the maintenance of constant osmotic pressure in the fluids of an organism by the control of water and salt concentrations.
Explant
the material removed from the plant during micropropagation eg meristem tissue from shoot tips or axial buds
systolic blood pressure (top number)
the maximum arterial pressure during contraction of the left ventricle of the heart
Forced expiratory volume
the maximum forced volume of air breathed out in 1s
Carrying capacity, k
the maximum population size that an environment can support
Biotic potential
the maximum possible growth rate of a population
oxidative phosphorylation
the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing energy which is used to reform ATP
activation energy
the minimum amount of energy need for a biological reaction to start
Second messenger model (of adrenaline action)
the model used to describe the action of adrenaline because it is non-steroid so cannot pass through cell membrane so relies on cAMP being created
mass flow
the movement of fluids down a pressure or temperature gradient
Emigration (as a factor affecting population size)
the movement of individual organisms away from a particular area decreasing their population size in that area
Immigration (as a factor affecting population size)
the movement of individual organisms into a particular area increasing the population size in that area
erector pili muscles
the muscles that when contracted make body hairs erect
Succession
the natural process in which early colonising species are replaced over time until a stable mature population is established
Innate/non-specific immunity
the natural resistances with which a person is born
Diffusion
the net movement of particles from a region of their higher concentration to a region of their lower cncentration
postsynaptic neurone
the neurone that recieves the neurotransmitter
abundance of organisms in an ecosystem
the number of individuals of a species present in an area at any given time
population (ecology)
the number of individuals of the same species in a given area at a given time
Saprobiotic nutrition
the obtainment of energy by an organism from dead or waste organic material
sense strand
the one of two DNA strands that contains the code for the protein to be synthesised, running from 5' to 3'
heamocoel
the open cavity in an open circulatory system, under a lower pressure
Cell cycle
the ordered sequence of events that take place in a cell resulting in it's division into genetically identical daughter cells.
humus
the organic component of soil, formed by the decomposition of leaves and other plant material by soil microorganisms.
Chance
the organisms selected may, by chance, not be representative of the whole population, effects can be minimised using a large sample size
antisense strand
the other strand from 3' to 5' that is a complementary copy of the sense strand and doesn't code for a protein
electrical balance of a cell
the overall charge of a cell created due to a higher conc. of +ve or -ve ions in or outside it
systole
the phase of the heartbeat when the heart muscle contracts and pumps blood from the chambers into the arteries.
diastole
the phase of the heartbeat when the heart muscle relaxes and allows the chambers to fill with blood.
sarcolemna
the plasma membrane that encloses muscle fibres
primary structure of proteins
the polypeptides chains made by condensation reaction of amino acid addition
locus of a gene
the position of a gene on a chromosome
Conservation
the preservation and careful management of the environment and of natural resources
diastolic blood pressure (bottom number)
the pressure in the arteries when the heart rests between beats
blood pressure
the pressure of the blood in the circulatory system
Ecological succcession
the process by which a biological community changes over time
bioleaching
the process by which hyperaccumulates take up metals from the ground
Positive/Darwinian selection
the process by which new advantageous genetic variants sweep a population
Respiration
the process by which organic molecules, such as glucose are broken down into smaller inorganic molecules like CO2 and H2O. The chemical energy stored in the bonds is used to make adenosine triphophate
co-transport
the process in which two substances are simultaneously transported across a membrane by one protein or protein complex that doesn't need ATP (facilitated diffusion) in this case H+ co-transports sucrose into companion cells
Cell Differentiation
the process of a less specialised cell become more specialised with a reduced potency
Hybridisation
the process of an animal or plant breeding with an individual of another species or variety.
Expiration/exhalation
the process of breathing out/expelling air from the lungs, a passive process
Captive breeding programmes
the process of breeding animals outside of their natural environment in restricted conditions in farms, zoos or other closed facilities. The choice of individual animals that are to be part of a captive breeding population, and the mating partners within that population, are controlled by humans.
Ultrafiltration
the process of filtration of blood in the kidneys to remove nitrgoenous waste and for osmoregulation
phosphorylation
the process of reattaching a phosphate group to an ADP molecule, a condensation reaction
Reclamation
the process of restoring ecosystems that have been damaged or destroyed
Chemiosmosis
the process of synthesis of ATP in both photosynthesis and respiration due to diffusion of protons from an area of their higher concentration to an area of their lower concentration passing through ATPase phosphorylating ADP
Inspiration/inhalation
the process of taking in air into the lungs for gas exchange
ornithine cycle
the process whereby ammonia produced in the deamination of proteins is converted into urea bby a set of enzyme-controlled reactions
genetic biodiversity is directly proportional to
the proportion of polymorphic gene loci
Preservation
the protection of an area by restricting or banning human interference, so that the ecosystem is kept in its original state. Commonly used to preserve ecologically, archaeologically, or paleontologically sensitive resources that can be easily damaged or destroyed by disturbances. Visitation is not allowed in preserved areas only by those who manage or monitor it.
mitotic spindles
the protein microtubules made by centrioles that attach to and control chromosmes
Surface area to volume ratio
the ratio of surface area to volume
selective reabsorption
the reabsorbtion of certain chemicals from glomerular filtrate by active transport, such as glucose, salt
haemoglobin
the red pigment that carries oxygen and gives them their colour
deamination of excess amino acids
the removal of an amine group from a molecule, body has no way of storing protein so rather than wasting it it removes the amino group forming ammonia then urea whilst remainder of amino acids is used in cellular respiration or converted into lipids for storage
sarcomere
the repeated functional subunit of a myofibril that is measured from one Z-line to the next
Pharmacogenetics
the science of combining drug actions with personal genetic material
Distal convoluted tubule
the second twisted tubule in the cortex after the loop of Henle where fine-tuning of the water balance of the body, pH and ion balance of the blood
Clonal selection
the selection of a specific complementary B cell that clones itself
vascular system
the series of transport vessels running through a plant
Cellular respiration
the set of catabolic metabolic reactions that take place in the cells of organisms to convert biochemical energy into ATP
Calvin cycle
the set of chemical reaction of carbon fixation and production of organic molecules by chloroplasts in the light-independent stage of photosynthesis
sarcoplasm
the shared cytoplasm of muscle fibres
Resolution
the smallest change in the quantity being measured that can be detected by an instrument
Proteomics
the study and amino acid sequencing of an organism's entire protein complement
synaptic knob
the swollen end of the presynaptic neurone that contains many mitochondria and endoplasmic reticulum for the synthesis of neurotransmitter
Autosomal/genetic linkage
the tendency of genes that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction which affects the typical phenotypic ratios of offspring
homeostasis
the tendency towards a relatively stable equilibrium between interdependent elements maintained by physiological processes.
The sliding filament model of muscle contraction
the theory that muscles contract due to the sliding of actin over myosin
myosin
the thicker protein filament of myofibrils that consists of long rod-shaped fibres with bulbous heads that project to one side
actin
the thinner protein filament of myofibrils made of 2 helical strands twisted round each other
Gross production
the total energy going into a trophic level that produces biomass eg producers, primary consumers
phagosome
the transport vesicle that encompasses the pathogen when it is engulfed by a phagocyte
haemolymph
the unpigmented blood of insects. Doesn't carry O2 or CO2, but transports food and nitrogenous waste products
Bioremediation
the use of microorganisms to break down pollutants and contaminants in the soil and water
Single-cell protein, SCP
the use of microorganisms to directly produce edible protein
indirect food production by biotechnology
the use of microorganisms to help produce foods by their actions on it eg. bread, cheese, wine
direct food production by biotechnology
the use of microorganisms to produce food from the microorganisms eg. Quorn
Recessive allele
the version of a gene that is only expressed if two copies of the allele (homologous recessive)
Dominant allele
the version of a gene that will always be expressed if present in an organism
ventilation rate
the volume of air inhaled in one minute
glomerular filtration rate
the volume of blood that is filtered through the kidneys per unit time
glomerular filtration rate (GMR)
the volume of filtrate filtered through the glomerulus per unit time
Ψs
the water potential due to a dissolved solute
Ψw
the water potential of a solution, taking into account Ψp+Ψs
features of all sensory receptors
they are specific to one type of stimulus and act as a transducer - they convert the stimulus energy into a nerve impulse
parenchyma cells (xylem)
thick-walled cells that pack around xylem vessels, storing food and tannin deposits
ventilation rate =
tidal volume x breathing rate
heterochromatin
tightly wound DNA which causes them to be visible during cell division
sinks
tissues in a plant that need assimilates eg for respiration, storage or protein synthesis for example roots, meristematic tissues, storage organs, fruits, seeds
Sources
tissues in a plant that produce assimilates eg green leaves, green stems, storage organs, food stores in germinating seeds
The Galapagos Islands problems caused by human activities
tourism, pollution of oceans - oil spills, sewage, habitat destruction, more roads/houses built, introduction of livestock causing interspecific competition with native species
ways in which genes are regulated categorised by the level at which they operate
transcriptional, post-transcriptional, translational, post-translational
translational (as a way in which genes are regulated)
translation can be stopped or started
intrinsic/integral protein
transmembrane proteins that are embedded through both layers. They have hydrophobic R-group amino acids on the outside, which interact with the hydrophobic core.
relay neurones
transmit electrical impulses from a sensory neurone to a motor neurone, found in CNS. Have many short dendrons and axons
sensory neurones
transmit electrical impulses from a sensory receptor cell to a relay neurone, motor neurone or brain. Have one dendron and one axon and cell body on side
motor neurones
transmit electrical impulses from relay neurone to an effector, such as a muscle or gland and have one long axon and many dendrites
translocation
transport of assimilates from source to sink through phloem
Phloem tissue
transport of organic nutrients like sucrose from leaves to rest of plant, composed of columns of sieve tubes, separated by perforated walls called sieve plates
role/function of blood
transport: O2 to and CO2 from respiring cells, digested food from small intestine, N waste from cells to excretory organs, hormones, food molecules from storage to active cells, platelets to damaged areas, cells and antibodies involved in immune response
Xylem tissue
transports water and minerals throughout plants, strengthened by hydrophobic lignin, also provides structural support for plants
renal dialysis
treatment for kidney failure where the function of the kidneys is carried out artificially
trachea in insects
tubes that carry air to the muscles of insects, has chitin lining which keep them open
Sister group on a phylogenetic tree
two descendants from the same node
Homologous pair of chromosomes
two of the same chromosomes one paternal one maternal
Collecting duct
urine passes down the collecting duct through the medulla to the pelvis, more fine-tuning of the water balance happens because the permeability of the walls is sensitive to ADH
medulla oblongata
used in autonomic control eg controls heart rate and breathing rate
Use of recombination frequency
used to map the genes on a chromosome for a number of characteristics coded for by genes on the same chromosome where 1% relates to a distance of one map unit on a chromosome
response to decreased core body temperature in endotherms
vasoconstriction, decreased sweating, raising body hair or feathers to increase insulating effect, shivering
response to increased core body temperature in endotherms
vasodilation, increased sweating, reducing the insulating effect of hair of feathers
hairpin bend of Loop of Henle role in countercurrent multiplier effect
very concentrated filtrate as lots of water left in descending limb, filtrate is hypertonic to blood
cytokinesis in plant cells
vesicles begin to assemble in metaphase plate until their membranes fuse together, then a cell wall forms inbetween.
synaptic vesicles
vesicles containing neurotransmitter that fuse with the presynaptic membrane and release their contents into the synaptic cleft
bile canaliculi
vessels in between hepatocytes in to which they secrete bile, which drains in to the bile ductules and then to the gall bladder
bile ductules
vessels that drain bile from the bile caniculi into the gall bladder
Examples of when primary succession occurs
volcanic eruptions, deposition of lava creating exposed igneous rock when it cools, when sand is blown by the wind or deposited by the sea to create new sand dunes, silt and mud are deposited at river estuaries, glaciers retreat depositing rubble and exposing rock
Vital capacity
volume of air that can be breathed in when the strongest possible exhalation is followed by the deepest possible inhalation
Tidal volume
volume of air that moves into and out of the lungs with each resting breathe
Principles of thermoregulation in endotherms: the most important ways in which they warm up and cool down
warm up by internal exothermic metabolic reactions, cool down by energy-requiring physiological responses
adhesion
water is attracted to other materials means it can be transported through xylem for example.
Ψp
water pressure due to the hydrostatic pressure caused by the pressure exerted by the walls of a closed container on the liquid
The Lake District National Park animals present
water voles, red squirrels, bats, golden eagle, toads, red deer
chlorine shift
when -ve hydrogen carbonate ions leave the cell, -ve chlorine ions enter the cell to balance the electrical balance of the cell
Oxyhaemoglobin
when Hb binds reversibly (loosely) with oxygen Hb(O2)4/HbO8 is formed
deletion (as a type of point mutation)
when a base is deleted so the whole code shifts down one base
insertion (as a type of point mutation)
when a base is inserted so the whole code shifts up one base
Cell Specialisation
when a cell becomes comitted to a specific activity
Pandemic
when a communicable disease spreads rapidly across a number of countries and continents
Epidemic
when a communicable disease spreads rapidly to a lot of people at a local or national level
resting potential/polarised definition
when a neurone is not transmitting an impulse, the p.d. across the membrane is the resting potential, the outside is more positive than axon cytoplasm so it is polarised
spatial summation
when a number of presynaptic neurones connect to one postsynaptic neurone, so when each release neurotransmitter the amount builds up and triggers an action potential in only one neurone
MHC/antigen complex
when a pathogen's antigen is bonded to a phagocyte's MHC and is displayed on the phagocyte's cell surface membrane
Water stress
when a plant loses more water through transpiration that it can uptake through it's roots in dry conditions
renaturation
when a protein denatured due to a change in pH resumes its normal shape when the optimum pH is restored
deletion (as a type of chromosomal mutation)
when a section of a chromosome breaks off and is lost within the cell
temporal summation
when a single presynaptic neurone releases neurtotransmitter due to a high frequency of incoming action potentials, so amount of neurotransmitter builds up to sufficient amount to trigger action potential in postsynaptic neurone
Homozygous dominant
when an organism contains 2 alleles of the dominant phenotype
Homozygous recessive
when an organism contains 2 alleles of the recessive phenotype
Heterozygous
when an organism contains two different alleles for a characteristic, one dominant and one recessive so the dominant phenotype is expressed
phloem loading
when assimilates are transported into phloem by active transport through either the symplastic or apoplastic routes
phloem unloading
when assimilates passively move out of phloem by diffusion in tissues with their lower concentration
carbominohaemoglobin
when carbon dioxide combines with the amino acids in the polypeptide chains these molecules are formed
crossing over
when chromatids break and reform when forming bivalents in Prophase I of meiosis
Stage 1 of an intraspecific competition graph
when is plentiful in a habitat all organisms have enough resources to survive and reproduce so the population size increases
bulk transport
when large molecules that cannot be moved in or out of a cell through active transport so do so by exocytosis or endocytosis.
phagolysosome
when lysosomes bind with the phagosome they release the enzymes that break down the pathogen in this structure
Mitotic phase
when mitosis and cytokinesis occur (only after interphase)
base substitution (as a type of point mutation)
when one base is substituted with another
positive cooperativity
when one molecule of O2 binds to the Hb it changes shape and makes it easier for the next O2 molecules to bind
how is an impulse started
when stimulus is detected by a sensory receptor the energy of the stimulus temporarily reverses the charge on the axon membrane to +40mV
Autoimmune diseases
when the body's own immune system recognises body cells as foreign/non-self and attacks them
G0 phase
when the cell leaves the cell cycle from G1 temporarily or permanently (because of cell differentiation, DNA damage so it cannot divide)
Cytokinesis
when the cytoplasm divides and two genetically identical daughter cells are produced
hyperpolarisation
when the p.d. is repolarised too much and goes lower than -70mV
beneficial (as an effect of a mutation)
when the phenotype of an organism is positively affected by a new and useful protein being synthesised
summation
when the release of one amount of neurotransmitter by a presynaptic neurone is not over the threshold and not enough to trigger an action potential so the amount of neurotransmitter needs to build up sufficiently
Cytolysis/haemolysis
when too much water enters an animal cell causing it to burst.
Co-dominance
when two different alleles of a gene are equally dominant so both are expressed in the phenotype of the organism
transpiration stream
when water evaporates from the freely-permeable cellulose cell walls of the mesophyll cells in the leaves into air spaces . The water moves out to the external air through the stomata down the diffusion gradient
transpiration pull
when water is drawn up the xylem in a continuous stream to replace the water lost by evaporation because of adhesion and cohesion of water that exhibit capillary action
Crenation
when water leaves an animal cell causing it to shrink and shrivel.
guttation
when xylem sap is forced out of special pores at night when transpiration is low and evidence of root pressure
neuromuscular junctions
where a motor neurone and a muscle cell (effector)
kidney transplant
where a new kidney from a donor is inserted in the groin area, needs to be correct 'tissue match' and immunosuppressent drugs need to be taken for rest of life
Distribution of organisms in an ecosystem
where individual organisms are found within an ecosystem
Nuetrophils
white blood cell, multi-lobed nucleus easier to small gaps to get to infections, granular cytoplasm has many lysosomes - proteins to break down pathogens
Lymphocytes
white blood cells
B lymphocytes
white blood cells synthesised in the bone marrow from haematopoietic cells
T lymphocytes
white blood cells that take part in the specific immune system and are made in the thymus gland. They secrete chemicals to kill cancerous or virus infected cells
Examples of in situ conservation methods
wildlife reserves, marine conservation zones
arborescent dicots
woody dicots that have hard, lignified tissues and a long life cycle