IB HL Biology

7 stem cell characteristics

Retain capacity to divide Produce cell cultures Repair tissue Undifferenciated Specialise in different ways Form organs Medical research

Repolarization

Return of the cell to resting state, caused by reentry of potassium into the cell while sodium exits the cell.

What is a nerve impulse?

Reversal of potential difference across a membrane

What 5 regions of DNA do not code for proteins?

STING - Satellite DNA (tandem repeats), Telomeres (chromosome ends), Introns (non-coding sequences), Non-coding RNA genes, Gene regulatory sequences

Isotonic:

Same solute concentration (no net flow)

What does acetylcholine cause during muscle contraction?

Sarcolemma depolarisation, causing calcium ions to be released from the sarcoplasmic reticulum

4 consumers

Scavengers, omnivore, carnivore and herbivore

fenestrations

Screen out blood cells and large proteins, preventing them from entering Bowman's capsule.

intestinal juice

Secreted by the walls of the small intestine, works with the pancreatic juice to chemically break down food and complete the digestive process.

Epithelium cells

Secretion, absorption, protection. Cells that line the interior and exterior body surfaces

Segregation

Separation of alleles during gamete formation

What is Mendel's Law of Independent Assortment?

Separation of alleles for one gene occurs independently of the separation of alleles for another gene

outer membrane of mitochondria

Serves as a barrier between the cytosol and the inner environment of the mitochondrion.

Example of an Autosomal Codominant disease:

Sickle cell anemia

What are separated during Meiosis II?

Sister chromatids

Okazaki fragments

Small fragments of DNA produced on the lagging strand during DNA replication, joined later by DNA ligase to form a complete strand.

Stomata

Small openings on the underside of a leaf through which oxygen and carbon dioxide can move

What was the first disease eradicated by vaccination?

Smallpox

What does transport in blood depend on?

Solubility

Antiobiotic Resistance

Some bacteria populations contain a few individuals with mutations which give resistance to drugs.

sacroplasmic reticulum

Specialized endoplasmic reticulum in muscle cells; stores and releases calcium ions

Antibodies

Specialized proteins that aid in destroying infectious agents

3 main stages of Anaphase:

Spindle fibres continue to contract Sister chromatids separate and move to opposite sides of the cell Sister chromatids are now regarded as two separate chromosomes

microtubules

Spiral strands of protein molecules that form a tubelike structure

How can ventilation rate be measured?

Spirometry (measures amount / rate of air)

What is the process of removing non-coding regions within genes and what are these regions called?

Splicing and introns

3 steps of gene transfer:

Step 1: DNA Extraction • Gene of interest isolated from organism • Gene is amplified using PCR (along with a plasmid) Step 2: Digestion and Ligation • Plasmid and gene cut with a specific restriction enzyme • Gene is spliced into plasmid vector by DNA ligase Step 3: Transformation and Expression • Recombinant plasmid is inserted into a host cell • Antibiotic selection may be used to select for successful transgenic cells (if plasmid has an antibiotic resistance gene) • Transgenic cells express new protein (for extraction / use)

Steriods

Steroids are a class of lipids that have a basic structure of four linked carbon rings and include cholesterol, vitamin D, and a variety of hormones.

3 types of chemical digestion

Stomach acids, bile and enzymes

Carb and Lipid differences: SODAS

Storage (lipids used for long term storage) Osmotic pressure (lipids easier to store) Digestion (carbohydrates easier to utilise) ATP yield (lipids store more energy per gram) Solubility (lipids insoluble / harder to transport)

Lipid cellular functions: SHIPS

Storage of energy (triglycerides) Hormonal roles (steroids) Insulation (thermal) Protection of organs Structural roles (cholesterol)

Example of a sink in a plant

Storage organs (seed)

Denaturation

Structural change in a protein that results in the loss (usually permanent) of its biological properties

Protein functions SHITME

Structure (collagen, spider silk) Hormonal (insulin, glucagon) Immunity (immunoglobulins) Transport (haemoglobin) Sensation (rhodopsin) Movement (actin, myosin) Enzymatic (Rubisco, catalase)

glomerular filtrate

Substances that filter out of the blood through the thin walls of the glomeruli

What 2 things does the mitochondrial matrix contain?

Suitable enzymes and an appropriate pH for Krebs cycle

5 other necessary elements for life

Sulfur: found in 2 amino acids Calcium: chemical messenger that helps regulate cell processes Phosphorus: ATP and DNA, RNA (phosphate) Iron: needed in cytochromes for electron transport chains, hemoglobin sodium: water balance/homeostasis, pumped into cells for water uptake, nerves

Schwann cells

Supporting cells of the peripheral nervous system responsible for the formation of myelin.

filament

Supports the anther

Synaptic Transmission (10)

Synapse is gap between adjacent neurons Arriving action potential depolarises pre-synaptic membrane Opens voltage-gated calcium channels in membrane Causes influx of calcium ions Causes synaptic vesicles to fuse with the pre-synaptic membrane Vesicles release neurotransmitter into synaptic cleft Neurotransmitter diffuses across synaptic cleft Binds to receptors on post-synaptic membrane Opens channels allowing potassium/sodium ions to diffuse Initiation of action potential in post-synaptic membrane

During Prophase I, homologous pairs of chromosomes form points of connection between non-sister chromatids, what is the name of the process that forms these connection points and what is the resulting complex called?

Synapsis and a bivalent

Rough Endoplasmic Reticulum

System of internal membranes within the cytoplasm. Membranes are rough due to the presence of ribosomes. functions in transport of substances such as proteins within the cytoplasm

binomial system of nomenclature

System of naming a species by the combination of the genus name and a specific epithet.

Helper T cells

T cells that help the immune system by increasing the activity of killer cells and stimulating the suppressor T cells

Bones are connected to muscles by...

Tendons

Benedict's test

Test for reducing sugars

What 5 labels of a seed structure are there?

Testa, cotyledon, radicle, epicotyl and micopyle

Why is carbon important?

Tetravalent (can form 4 covalent bonds), which allows it to produce a variety of stable organic compounds

What did Hershey and Chase conclude?

That the genetic material of the bacteriophage was DNA, not protein

What is the cell cycle?

The Cell cycle is the period between one cell divsion and the next. Interphase is an active period in the life of a cell

Bioaccumulation

The accumulation of a substance, such as a toxic chemical, in various tissues of a living organism

Shoots

The aerial portion of a plant body, consisting of stems, leaves, and flowers.

gross production of energy

The amount of organic matter (biomass) produced by plants, expressed as energy per unit area per unit time period

Biochemical oxygen demand

The amount of oxygen required by aerobic microorganisms to decompose the organic matter in a sample of water. It is used as a measure of the degree of water pollution. Also referred to as biological oxygen demand

Vitalism

The belief that living organisms possess a non physical inner force or energy that gives them the property of life

ester bond

The bond formed when fatty acid molecules are joined to glycerol molecules in condensation reactions.

Edge effect

The changes in population or community structures that occur at the boundary of two habitats

peptide bond

The chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid

Proteomes

The complete complement of proteins that a cell or organism can make

Decarboxylation

The complete loss of a carboxyl group as carbon dioxide

resting potential

The difference in electric charge between the inside and outside of a neuron's cell membrane

electrochemical gradient

The diffusion gradient of an ion, representing a type of potential energy that accounts for both the concentration difference of the ion across a membrane and its tendency to move relative to the membrane potential.

Age structure

The distribution of a population's individuals among various age groups

What is mitosis

The division of a diploid (2 sets of chromosomes) nucleus to form two genetically identical daughter nuclei

ecological niche

The ecological role and space that an organism fills in an ecosystem or the ecological role and space that an organism fills in an ecosystem

End product inhibition/Feedback inhibition

The end product of pathway acts as an inhibitor for an enzyme in the pathway, thus slowing it down.

Habitat:

The environment in which a species lives or the normal location of an organism

G1 phase

The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins.

primary structure

The first level of protein structure; the specific sequence of amino acids making up a polypeptide chain.

follicular phase

The first phase of the ovarian cycle, during which a follicle (an oocyte and its surroudning cells) enlarges and matures. This phase is under the control of FSH from the anterior pituitary, and typically lasts from day 1 to day 14 of the menstrual cycle. The follicle secretes estrogen during this time period.

allopatric speciation

The formation of new species in populations that are geographically isolated from one another.

sympatric speciation

The formation of new species in populations that live in the same geographic area

menstral cycle

The hormone-controlled cycle in the human female, lasting about a month, in which an egg matures and is released from the ovary and the uterus prepares to receive it.

What is 'mass flow' in phloem transport?

The incompressibility of water causes the sap volume to be increased, creating a pressure gradient

carbon fixation

The initial incorporation of carbon into organic compounds.

Mucosa

The innermost layer of the human digestive tract; in some parts of the digestive system, it contains mucus-secreting cells and glands that secrete digestive enzymes

Aorta

The large arterial trunk that carries blood from the heart to be distributed by branch arteries through the body.

descending limb

The limb of the loop of Henle that carries fluid from the cortex towards the medulla of the kidney

Leaching

The loss of water-soluble nutrients from the soil, due to rain and irrigation. Nutrients lost from soils enter aquatic ecosystems

natural gas and oil

The main energy products currently being obtained from the seafloor

Phosphorylation

The metabolic process of introducing a phosphate group into an organic molecule.

receptor-mediated endocytosis

The movement of specific molecules into a cell by the inward budding of membranous vesicles containing proteins with receptor sites specific to the molecules being taken in; enables a cell to acquire bulk quantities of specific substances.

synaptic cleft

The narrow gap that separates the presynaptic neuron from the postsynaptic cell.

peritubular capillaries

The network of tiny blood vessels that surrounds the proximal and distal tubules in the kidney

Leading strand

The new continuous complementary DNA strand synthesized along the template strand in the mandatory 5' to 3' direction.

fundamental niche

The niche species could potentially occupy.

Biodiversity

The number and variety of organisms found within a specified geographic region or ecosystem

Overpopulation

The number of people in an area exceeds the capacity of the environment to support life at a decent standard of living.

Cervix

The opening to the uterus

carbon cycle

The organic circulation of carbon from the atmosphere into organisms and back again

longitudinal muscle

The outer layer of smooth muscle in the wall of the digestive tract. When the longitudinal muscle contracts the tube shortens.

Bronchi

The passages that direct air into the lungs

sex linkage

The presence of a gene on a sex chromosome; (e.g., hemophilia, color-blindness)

nitrification

The process by which ammonia is converted to nitrite (NO2-) and then nitrate (NO3-) by microorganisms

clonal selection

The process by which an antigen selectively binds to and activates only those lymphocytes bearing receptors specific for the antigen. The selected lymphocytes proliferate and differentiate into a clone of effector cells and a clone of memory cells specific for the stimulating antigen.

absorption

The process by which nutrient molecules pass through the wall of the digestive system into the blood

Inheritance

The process by which physical and biological characteristics are transmitted from the parent (or parents) to the offspring

Implantation

The process by which the zygote attaches to the uterine wall

Depolarization

The process during the action potential when sodium is rushing into the cell causing the interior to become more positive.

Captive breeding

The process of breeding animals in controlled environments within well-defined settings, such as wildlife reserves and zoos

Classifcation

The process of grouping things based on their similarities domain, kingdom, phylum, class, order, family, genus, species

Capping

The process of linking a methyl residue to the 5' end of eukaryotic RNAs. The 5' cap protects the mRNA from degradation and is required for translation in the cytoplasm.

selective breeding

The process of selecting a few organisms with desired traits to serve as parents of the next generation

Ultrafiltration

The process where small molecules are forced from the blood out of the capillaries of the glomerulus, under high pressure, into the Bowman's capsule.

oxidative phosphorylation

The production of ATP using energy derived from the redox reactions of an electron transport chain; the third major stage of cellular respiration.

peripheral proteins

The proteins of a membrane that are not embedded in the lipid bilayer; they are appendages loosely bound to the surface of the membrane.

absorption spectrum

The range of a pigment's ability to absorb various wavelengths of light.

Zone of stress

The range of values of an abiotic factor that an organism can survive but are not optimal

nucleoid region

The region in a prokaryotic cell consisting of a concentrated mass of DNA.

synaptic transmission

The relaying of information across the synapse by means of chemical neurotransmitters.

corpus albicans

The scar tissue that replaces the corpus luteum. it is caused by the drop of LH levels in the blood at the end of the 28 day-cycle. as soon as progesterone production ends, the corpus luteum begins to degenerate and is replaced by this.

Genetics

The scientific study of heredity

G2 phase

The second growth phase of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs.

secondary structure

The second level of protein structure; the regular local patterns of coils or folds of a polypeptide chain.

efferent arteriole

The small artery that carries blood away from the capillaries of the glomerulus.

afferent arteriole

The small artery that carries blood toward the capillaries of the glomerulus.

Describe what happens in the S phase

The stage during which DNA is replicated

Style

The stalk of a flower's carpel, with the ovary at the base and the stigma at the top.

stigma

The sticky part of a flower's carpel, which receives pollen grain.

lagging strand

The strand that is synthesized in fragments using individual sections called Okazaki fragments

S phase

The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated.

tertiary structure

The third level of protein structure; the overall, three-dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain.

luteal phase

The third phase of the ovarian cycle, during which a corpus luteum is formed from the remnants of the follicle that has ovulated its oocyte. The corpus luteum secretes progestrone and estrogen during this time period, which typically lasts from day 15 to day 28 of the menstrual cycle. Formation of the corpul luteum is triggered by the same LH surge that triggers ovulation, however in the absence of LH (levels quickly decline after the surge) the corpus luteum begins to degenerate.

Pollination

The transfer of pollen from male reproductive structures to female reproductive structures in plants

guard cells

The two cells that flank the stomatal pore and regulate the opening and closing of the pore.

Phloem

The vascular tissue through which food moves in some plants

What is the Null Hypothesis (H0) (genes)?

There is no association (genes are unlinked)

podocytes

These cells form a porous membrane surrounding the endothelial cells of the glomerulus.

If a plaque ruptures, blood clotting is triggered, and forms a ______

Thrombus

In a chloroplast, granum are made up of stacks of _________ to...

Thylakoids to increase SA available for ETC

Lyme disease

Tick-borne disease caused by the spirochete Borrelia burgdorferi.

What is the refractory period?

Time taken to reach equilibrium

elastic tissue

Tissue containing the protein elastin, which is able to stretch and recoil.

Why is the intermembrenal space of the mitochondria small?

To maximise the electrochemical gradient that results from proton accumulation

Why do eukaryotic cells modify RNA after transcription?

To produce mature mRNA

heritable

Traits that can be passed on to offspring

Genetic modification example (11)

Transfer of genes from one organism to another Maize crops modified Using Bt toxin gene Makes resistant to pests Produce higher crop yield Less land needed Less pesticide needed Beneficial insects may be harmed Gene might spread to other plants Allergic reactions when crop eaten Only favoured countries have technology

Optogenetics

Transgenic technique that combines genetics and light to control targeted cells in living tissue

What do Gibberellins do?

Trigger germination and stem elongation

What causes a tumor?

Tumors are the result of uncontrolled cell division, which can occur in any organ or tissue.

What do nitrifying bacteria do?

Turn ammonia in decaying matter into nitrates

What are meristems?

Undifferentiated cells in plants that are capable of indeterminate growth

What type of movement is peristalsis and what muscles contract to allow it to happen?

Unidirectional and sequential longitudinal muscles

atrioventricular valves

Valves located between the atrial and ventricular chambers on each side of the heart, prevent backflow into the atria when the ventricles are contracting.

Difference between Monocotyledon and Dicotyledon stems.

Vascular bundles in Monocotyledon are more scattered, Dicotyledon's are arranged in a circle

Viruses

Viruses can only reproduce inside host cells, and they damage the cell when they do this

High boiling point

Water has a boiling point of 100°C

Compare the properties of water vs. methane (think thermal properties)

Water has almost 2x the specific heat capacity of methane, water heat of vaporization is almost 3x that of methane, melting and boiling points of methane are lower than water

Density property of water

Water is less dense as a solid than as a liquid, due to H bonding. Crystalline lattice keeps molecules at a distance.

High specific heat capacity

Water requires a lot of energy to change temperature

transient polymorphism

When one allele is gradually replacing another ex: Black and white moth -> industrial pollution

Formation of coal

When peat is compressed under layers of sediment, heat and pressure remove moisture to transform it into coal

Autosomal gene linkage

When the genes are on the same autosome

Falsification of Vitalism

When urea (organic compound in liver) was artificially synthesized by German chemist Friedrich Wöhlerfor the first time, vitalism was deemed false.

Reproductive status

Whether an organism is capable of participating in the process of reproduction

Which sex chromosome is larger?

X

What does Iron do?

Yellow leaves

Do unsaturated Fatty Acids have double bonds and what form are they at room temperature?

Yes and liquid (plan oils)

conjugated protein

a biochemical compound, such as hemoglobin, made up of a protein molecule and a non-protein prosthetic group.

Methylation

a biochemical process that influences behavior by suppressing gene activity and expression

Nuceloside Triphosphates

a building unit for RNA

primary spermatocyte

a cell that divides to form two secondary spermatocytes

What is a mutation?

a change in an organisms genetic code. A mutation/change in the base sequence of a certain genes can result in cancer.

Uninformative Character

a character that fails to help distinguish among the possible trees in a parsimony analysis because its distribution requires the same number of evolutionary changes on all of them

Insecticides

a chemical that kills insects

monoclonal antibodies

a collection of identical antibodies that interact with a single antigen site

innate immune system

a collection of nonspecific barriers and cellular responses that serve as an inborn first and second line of defense against pathogens

Down Syndrome

a condition of intellectual disability and associated physical disorders caused by an extra copy of chromosome 21.

Link reaction

a decarboxylation reaction that occurs in the mitochondrion between glycolysis and the Krebs cycle.

Stargardt's disease

a degenerative eye disease that has been the target of stem cell research.

neurodegenerative disease

a disorder characterised by a progressive decline in the structure, activity and function of brain tissue

R group

a functional group that defines a particular amino acid and gives it special properties.

Regulator genes

a gene determining the production of a protein that regulates or suppresses the activity of one or more structural genes

sickle cell anemia

a genetic disorder that causes abnormal hemoglobin, resulting in some red blood cells assuming an abnormal sickle shape

Polyphyly

a group that does not uniquely share a common ancestor - undesirable classification

Paraphyly

a group with an ancestor and only some of its descendants - undesirable classification

Gene definition:

a heritable factor that consists of a sequence of DNA and influences a specific trait

transition state

a high-energy intermediate state of the reactants during a chemical reaction that must be achieved for the reaction to proceed

dichotomous key

a key for the identification of organisms based on a series of choices between alternative characters

Pentadactyl limb

a limb with five digits, such as a human hand or foot, which is found in many amphibia, reptiles, birds, and animals, which can allow us to deduce that all species in these categories derived from one common ancestor.

plaque rupture

a major cause of coronary thrombi

Body Mass Index (BMI)

a measure of body weight relative to height

Biodiversity Index

a measurement of biodiversity in a given area calculated by dividing the number of species counted by the number of individual organisms counted

transect

a method of sampling at regular positions across an ecosystem to investigate whether the distribution of a plant or animal species is correlated with an abiotic variable

Electron tomography

a method used to generate a three-dimensional image of the inner mitochondrial membrane.

Neurons

a nerve cell; the basic building block of the nervous system

capillary bed

a network of capillaries in a tissue or organ

action potential

a neural impulse; a brief electrical charge that travels down an axon

ganglion cell

a neuron located in the retina that receives visual information from bipolar cells; its axons give rise to the optic nerve

Chernobyl accident

a nuclear power plant accident near Kiev, Ukraine in 1986

bivalents

a pair of homologous chromosomes

What is a Xerophyte?

a plant adapted to reduce water loss (reduce transpiration)

Autoradiography

a procedure that locates radioactive substances in a slice of tissue; the radiation exposes a photographic emulsion or a piece of film that covers the tissue

dialysis

a procedure to remove waste products from the blood of patients whose kidneys no longer function

Mutations

a random error in gene replication that leads to a change

Meristem

a region of plant tissue, found chiefly at the growing tips of roots and shoots and in the cambium, consisting of actively dividing cells forming new tissue.

complete dominance

a relationship in which one allele is completely dominant over another

cross-pollination

a reproductive process in which pollen from one plant is transferred to the stigma of another plant

Biotic index

a scale for showing the quality of an environment by indicating the types of organisms present in it

limestone

a sedimentary rock consisting mainly of calcium that was deposited by the remains of marine animals

Promoter region

a sequence of DNA that initiated transcription of a particular gene and is needed to turn a gene on or off

Anaphylaxis

a severe response to an allergen in which the symptoms develop quickly, and without help, the patient can die within a few minutes.

keystone species

a species that has an unusually large effect on its ecosystem relative to its abundance

chi squared test

a statistical test of the fit between a theoretical frequency distribution and a frequency distribution of observed data for which each observation may fall into one of several classes.

rudimentary organs

a structure that has lost much or all of its ancestral function

Neonicotinoids

a systemic agricultural insecticide resembling nicotine.

gel electrolysis

a technique used to separate macromolecules on the basis of their size and charge with the use of electrical current

bird flu

a type of flu caused by the H5N1 virus

direction selection

a type of natural selection in which one extreme phenotype is favored over all others

hydrophobic interactions

a type of weak chemical interaction caused when molecules that do not mix with water coalesce to exclude water

pulmonary veins

a vein carrying oxygenated blood from the lungs to the left atrium of the heart.

What arrangement are starch's subunits bound and what 2 forms are there?

a-glucose subunits and amylose and amylopectin

Tumours

abnormal proliferation of cells, either benign or malignant.

Overhydration

above normal amounts of water in extracellular spaces

greenhouse gases

absorb infrared radiation and reflect it to earth

protein filaments

actin and myosin

Elongation

addition of amino acids to the polypeptide chain; continues until it reaches a stop codon

Allele definition:

alternate forms of a gene that code for the different variations of a specific trait

polysome

an arrangement of many ribosomes along a molecule of mRNA

Triglycerides

an energy-rich compound made up of a single molecule of glycerol and three molecules of fatty acid.

pelvis of kidney

an expansion of the upper end of the ureter

primary follicle

an immature ovum enclosed by a single layer of cells

MRSA (methicillin-resistant Staphylococcus aureus)

an infection caused by specific bacteria that has become resistant to many antibiotics

parasitism

an organism lives on or in a host to benefit itself and harm but usually not kill the host

hermaphrodite

an organism that has both male and female reproductive organs

Plesiomorphy

ancestral character state

Vertebrates

animals with backbones

Penicillin

antibiotic

Immuglobins

antibodies

heart disease

any disease of the heart muscle or other working parts of the heart

genetic disease

any disorder caused directly by a genetic mechanism

2 types of meristematic tissue

apical and lateral

Respirometer

apparatus for the measurement of respiratory gaseous exchange.

Bioinformatics

application of mathematics and computer science to store, retrieve, and analyze biological data

nurse cells

are found in the seminiferous tubules, form the blood-testis barrier, and coordinate spermatogenesis.

gyres

areas in the ocean where plastic trash accumulates. A large system of rotating ocean currents, there are five major rotating currents in the Earth's oceans

natural cloning

asexual reproduction

communities

assemblages of different populations that live together in a defined area

channel membrane protein

assists movement of certain substances across the membrane by creating an opening

immobilized enzymes

attachment of enzymes to another material or into aggregations so the movement of enzyme is restricted

E. coli

bacteria

ABO blood groups

based on having an A, B, both or no antigens on red blood cells

flex

bend

Single stranded binding proteins

bind to and stabilize single-stranded DNA

renal vein

blood vessel that carries blood away from the kidney and toward the heart

renal artery

blood vessel that carries blood to the kidney

blood system

body system that includes blood and all its component parts

Hydrolisis

bonds between monomers are broken by adding water (digestion)

Amylopectin

branched starch

Nucleases

break down nucleic acids

Catabolism

breakdown of complex molecules into simpler molecules (ex. digestion, respiration)

Sucrase

breaks down sucrose

inspiration

breathing in

Exspiration

breathing out

pedigree charts

can be used to track genetic information over several generations

Oncogens

cancer causing genes

malignant

cancerous

malignant

cancerous; cells migrate to other tissues or organs

carbon compounds

carbohydrates, lipids, nucleic acid, proteins

Artieries

carry blood away from the heart

Islets of Langerhans

cell clusters in the pancreas that form the endocrine part of that organ

cytokinesis

cell division; cytoplasm divides

Lysosome

cell organelle filled with enzymes needed to break down certain materials in the cell

metastasis

cells from a primary tumor migrate to other tissues and form new secondary tumors

mesophyll cells

cells that contain many chloroplasts and host the majority of photosynthesis

anaphase

centromeres split, spindle fibers shorten, sister chromatids are pulled apart

fatty acids

chains of carbon atoms bonded to hydrogen atoms

the edge effect

changes that occur in the ecology of an ecosystem around its edges

base substitution

changes the base of a single DNA nucleotide

emergent properties

characteristics of a whole organism

Photolysis of water

chemical decomposition of water induced by light.

Hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

non-sister chromatids

chromatids belonging to homologous chromosomes

Define the terms chromosome, gene, allele and genome (4)

chromosome: structure formed by DNA and proteins gene: a heritable factor that controls a particular characteristic allele: one specific form of a gene occupying the same gene locus as other alleles of the gene genome: the whole of the genetic info of an organism

chromatin

chromosomes prior to supercoiling

phagocytic leukocytes

circulate blood and goes to body tissue in response to infection

Dipeptidases

cleave the peptide bonds of dipeptides to release free amino acids

coagulation

clotting of blood

Agglutination

clumping of red blood cells

Photosystem

cluster of chlorophyll and proteins found in thylakoids

genetic code

collection of codons of mRNA, each of which directs the incorporation of a particular amino acid into a protein during protein synthesis

ecosystem

community and abiotic environment

Solution

completely homogenous mixture, diffused solute in solvent

surfactants

compounds that lower the surface tension of water

biomagnification

concentration of pollutants in the tissues of organisms. The process, in an ecosystem, in which a higher concentration of a substance in an organism is obtained higher up the food chain

Polyploidy

condition in which an organism has extra sets of chromosomes

Conifernophyta

coniferous trees

joint capsule

connective tissue that encloses the cavity and retains the fluid

lots of algae dies, things decompose it, they take all the oxygen, theres no oxygen for fish, fish die

consequences of eutrophication

High latent heat of vaporization

considerable amounts of heat are needed to evaporate water because hydrogen bonds have to be broken

Unsaturated fat (oils)

contain double bonds between carbons in fatty acid

inner membrance of mitochondria

contains electron transport chain and ATP synthase for oxidative phosphorylation

mitocondrial matrix

contains enzymes and specific pH

nitrogen fixation

conversion of atmospheric nitrogen in ammonia for plants and other organisms to then assimilate.

What do nitrogen fixing bacteria do?

convert atmospheric nitrogen into ammonium compounds

peptide bond

covalent bond formed between amino acids

Peptide bonds

covalent bonds (carboxyl group to amino group)

Disaccharides

covalent bonds between 2 monosaccharides formula=C12H22O11 (because a water molecule is lost in dehydration synthesis) Examples: -sucrose=glucose and fructose (transported by phloem in plants) -maltose=glucose and glucose -lactose=(milk sugar) glucose and galactose

What does DNA ligase do in DNA replication?

covalently joins the Okazaki fragments together

germinal epithelial cells

create spermatogonia from stem cells in the walls of the seminiferous tubes

Bowman's capsule

cup-shaped strucutre of the nephron of a kidney which encloses the glomerulus and which filtration takes place.

coronary thrombosis

damage to the heart muscle caused by a thrombus blocking a coronary artery

ocean acidification

decreasing pH of ocean waters due to absorption of excess atmospheric CO2 from the burning of fossil fuels

sink

delivered for use/storage

Apomorphy

derived trait

Ecological succession

describes the process by which a sequence of increasingly complex communities develop over time

actin strands

develop a Z shaped pattern in skeletal muscles (darker in color)

food web

diagram showing all feeding relationships in a community

Evolutionary Clock

differences in amino acids and DNA sequences accumulate over time, so closer matching species will have a more recent common ancestor.

mutualism

different species living together in a close relationship

Bubonic Plague

disease brought to Europe from the Mongols during the Middle Ages. It killed 1/3 of the population and helps end Feudalism. Rats, fleas.

Pathogens

disease causing agents

Rf value =

distance component travels ÷ distance solvent travels

cytokinesis in plant cells

divide from inside out using a cell plate in middle of cell

Eukaryota

domain of organisms that contain nuclei, includes animals, plants, fungi, and protists

feed conversion ratio

efficiency with which a species uses food (intake of food(g)/net production of biomass(g))

Molecule

elements covalently bonded

embryonic stem cells

embryonic cells, which can develop into any type of body cell

thyroid gland

endocrine gland that surrounds the trachea in the neck

List the purposes of fats

energy storage, organ cushioning, and thermal insulation

activation energy

energy that is needed to get a reaction started

mutagen

environmental factors that cause mutations

lactase

enzyme that breaks down lactose

Rubisco

enzyme that converts inorganic carbon dioxide molecules into organic molecules during the final step of the Calvin cycle

lactose free milk

enzymes are added to break down lactose

cortical reaction

enzymes prevent any other sperm from binding to the egg

Give an example of enzyme inhibition in medicine

ex. Ethanol is used as competitive inhibitor for alcohol dehydrogenate to treat antifreeze poisoning

tumor

excess of cells that are produced when cell division goes unchecked

algal bloom

excessive multiplication of algae A dense spread of algae on the surface of water caused by a rapid population growth

vulva

external female genitalia; includes the labia, hymen, clitoris, and vaginal orifice

type 1 pneumocytes

extremely thin alveolar cells that are adapted to carry out gas exchange

limits of tolerance

extremes of environments at which an animal can survive a.k.a zones of stress

sense organs

eyes, ears, nose, skin, taste buds

decay

fading away of memory over time

diversity increases, plant density increases, organic matter in the soil and soil depth increase as dead things pile up, water speed increases, soil erosion is reduced, nutrient recycling increases

features of primary succession

Resource partitioning leads species to

feed at different times, utilize slightly different prey, develop different physiological adaptations, live in slightly different regions

Detritivores

feed on plant and animal remains and other dead matter

Fillcinophyta

ferns

Zygotes

fertilized eggs

cotyledon

first leaf or first pair of leaves produced by the embryo of a seed plant

proximal convoluted tubule

first section of the renal tubule that the blood flows through; reabsorption of water, ions, and all organic nutrients

Platyhelminthes

flatworms

Peduncle

flower stalk

interstitial fluid

fluid between cells

Stroma

fluid portion of the chloroplast; outside of the thylakoids

What is the secondary structure of a protein?

folding into α-helix or β-pleated sheet

G1 phase

follows mitosis; period of cell growth

disruptive selection

form of natural selection in which a single curve splits into two; occurs when individuals at the upper and lower ends of a distribution curve have higher fitness than individuals near the middle

temporal isolation

form of reproductive isolation in which two populations reproduce at different times

Polypeptides

formed by condensation reaction, multiple amino acids

spermatids

four haploid cells that are formed when a diploid reproductive cell divides meiotically

nephron

functional unit of the kidney

reduction

gain of electrons

Discuss the role of genes and chromosomes in determining individual and shared character features of the members of a species ( 7)

genes - mutation changes genes - genes can have multiple alleles - different alleles of a gene code for different characteristics - e.g. eye colour - alleles may be dom or rec - both alleles influence the char with codominance - all members of a species are genetically similar and share genes - not all genes are expressed in an individual - genes are inherited from parents

oncogenes

genes with the potential to cause cancer

Heamophilia

genetic disorder where the bodies ability to control blood clotting is impaired

Genotype

genetic makeup of an organism

altrical species

give birth to relatively helpless offspring

biotic index

gives an overall assesment of the health of an ecosystem (sum of # of individuals of indicator species x pollution tolerance rating for all indicator species over the total # of indicator species)

Are clustered ecosystems with corridors good or bad?

good

net production of energy

gross production of energy-energy used for respiration, amount of energy converted to biomass The amount of organic matter produced by plants minus what is needed for plant respiration, expressed as energy per unit area per unit time period

Population

group of individuals of the same species that live in the same area

Community

group of organisms living and interacting

Anticodon

group of three bases on a tRNA molecule that are complementary to an mRNA codon

apical meristem

group of undifferentiated cells that divide to produce increased length of stems and roots

gestation

growth process from conception to birth

benign

harmless

Monounsaturated fats

have only one double bond

obesity

having an excess amount of body fat

amphipatic

having both a hydrophilic region and a hydrophobic region

spindle fibers

help pull apart the cell during replication and are made up of microtubules

Saprotrophs

heterotrophs that obtain organic nutrients from detritus by external digestion.

cristea of mitochondria

highly folded to increase SA:V ratio

HCG

human chorionic gonadotropin

Trans fats

hydrogen atoms on opposite sides of the double bond (produced by artificial partial hydrogenation of oils, no bend in fatty acid), solid at room temperature

Cis fats

hydrogen atoms on same side of double bond (typical natural isomer bend in fatty acid), liquid at room temperature

non-polar tails

hydrophobic

Loss of water lowers the _ _ _ _ _ _ _ _ _ _ _ pressure at the sink, maintaining the pressure gradient (and mass flow)

hydrostatic

monozygotic twins

identical twins

oocyte

immature egg

grandular cells

in stomach lining and intestines, produce enzymes

deoxynucleoside triphosphates

individual nucleotides with three phosphate groups

Tuberculosis (TB)

infectious disease caused by Mycobacterium tuberculosis; lungs usually are involved, but any organ in the body may be affected

second line of defense

inflammatory response

Silencers

inhibit transcription

endometrium

inner lining of the uterus

medulla of kidney

inner portion of kidney, composed of collecting tubules that empty into the renal pelvis

Arthropoda

insects

Aphids

insects that penetrate the plant phloem and feed on the dissolved food. They act as plant pathogens and are also vectors that carry pathogenic viruses, bacteria, and fungi into healthy plant tissue

transmembrane proteins

integral proteins that do not extend all the way through the membrane.

A node of Ranvier (myelin sheath gap)

is a bare region of axonal membrane in myelinated axons only.

Food conversion ration

is a measure of an animal's efficiency in converting feed mass into the mass of desired output

Cnidaria

jellyfish

synovial fluid

joint-lubricating fluid secreted by the synovial membrane

Polymers

large compound formed from combinations of many monomers

mature follicle

large, fluid-filled follicle ready to expel secondary oocyte during ovulation

maximum sustainable yeild

largest amount of fish that can be harvested without a decline in stocks

half-life

length of time required for half of the radioactive atoms in a sample to decay

Endemic species are

limited to just one location, such as an island

Steroids

lipids with 4 fused carbon rings Example: Cholesterol -used in cell membranes -precursor for other steroids (sex hormones) -atherosclerosis

seminal vescicles

located behind the bladder and above the prostate gland. The seminal vesicles contribute fluid to the ejaculate.

sieve element cells

long and narrow cells that are connected together to form the sieve tube

List the purposes of lipids

long term storage, more energy/gram (lighter energy storage), insoluble in water so they don't cause problems with osmosis

Oxidation

loss of electrons

What does the small subunit of a ribosome contain?

mRNA binding site

Gene transfer (9)

mRNA coding for factor extracted from human cell mRNA copied to DNA Plasmids used Endonuclease cut DNA Complementary bases on gene link gene to plasmid Sealed using ligase Recombinant plasmid containing gene taken up by bacteria Clone recombinant bacteria Bacteria cultured

Control of gene expression in Eukaryotes (10)

mRNA conveys genetic information from DNA to ribosomes Requires production of specific mRNA through transcription Some genes are only expressed at certain times Cell differentiation involves changes in gene expression Transcription factors can increase/decrease transcription Hormones can affect gene expression Transcription factors may prevent/enhance binding of RNA polymerase Nucleosome limit access of transcription factors to DNA Methylated genes are silenced Introns may contain positive or negative gene regulators

initiation

mRNA is attached to a subunit of the ribosome, the first codon is always AUG

nucleic acids

macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus

Image size =

magnification x real size

biomass litter and soil

main storage compartments of nutrients

DNA amplification by PCR

make large copies of DNA, studied further with a small sample, not to copy entire DNA, selected using a primer which binds by complementary base pairing

companion cells

make up phloem vessels, along with sieve tube elements

testis

male reproductive organ that produces sperm and hormones

pregnancy test

measurement of human chorionic gonadotropin (HCG), a hormone in blood and urine that indicates pregnancy

Integrins

membrane proteins; they transmit signals between the ECM and cytoskeleton

capture-mark-release-recapture, quadrat sampling, echo sounding, age profiling

methods of estimating population size

electron microscope

microscope that forms an image by focusing beams of electrons onto a specimen

inorganic nutrients

minerals and water

fluid mosaic model

model that describes the arrangement and movement of the molecules that make up a cell membrane

RNA splicing

modification of RNA to remove introns and rejoin remaining exons

petals

modified leaves which are usually bright in color to attract pollinators.

Mollusca

mollusks

amino acids

monomers of proteins

Polyunsaturated fats

more than one double bond

Bryophyta

mosses

simple diffusion

movement of a solute from an area of high concentration to an area of low concentration

Ventilation

movement of air in and out of the lungs

translocation

movement of organic compounds from sources to sinks

local current

movement of positive charges parallel to the inner and outer surfaces of the membrane

antagonistic muscles

muscle pairs arranged to work against each other to move a joint

circular muscle

muscle that forms a ring around a body opening

Explain how skeletal muscle contracts

muscles / fibres / myofibrils contain (repeating) units called sarcomeres; muscle / sarcomeres contain actin filaments and myosin filaments; actin fibres are thin and myosin fibres are thick; arriving action potential causes release of Ca2+; from sarcoplasmic / endoplasmic reticulum; Ca2+ binds to troponin; causing troponin and tropomyosin to move (on actin); exposing binding sites on actin / for myosin; ATP binds to myosin heads releasing them / breaking cross bridges; ATP hydrolysed / split into ADP + Pi; ATP / energy causes myosin heads to change shape / swivel / become cocked; myosin heads bind / form cross-bridges to (exposed) actin binding sites; myosin heads swivel / move actin (releasing ADP + Pi); myosin filaments move actin filaments towards centre of sarcomere; sliding of filaments / actin and myosin shortens the sarcomere;

levers

muscles attach to bones to help provide movement

carcinogens

mutagens that cause cancer

symbiotic relationship

mutualism, commensalism, parasitism

cross bridges

myosin head, which connects thick filaments and thin filaments during a contraction

amniocentesis

needle puncture of the amniotic sac to withdraw amniotic fluid for analysis

Rapid Bulking

new plants genetically identical via genetic modification

realized niche

niche a species actually occupies. The part of fundamental niche that an organism occupies as a result of presence of limiting factors in its habitat

uric acid

nitrogenous waste excreted in the urine

Explain how an error in meiosis cam lead to Down Syndrome (8)

non-disjunction chromatids dont separate non-separation of chromatids occurs during A1 due to incorrrect spindle attachment non-separation of chromatids during A2 due to centromeres not dividing occurs during gamete formation less common in sperm than egg formation down syndrome due to extra chromosome 21 gamete receives two chromosomes of the same type trisomy/ total 47 chromosomes

energy is

not recycled

mitosis

nuclear division

free nucleotides

nucleotides that have not been joined together to form a DNA or RNA strand

Mitotic index =

number of cells in mitosis/total number of cells

functions of life

nutrition, metabolism, growth, response, excretion, homeostasis, reproduction

termination

occurs when a stop codon in the mRNA reaches the A site of the ribosome

polygentic inheritance

occurs when more than one gene affects a trait

Acetylation

of DNA and histones causes nucleosomes to loosen and spread apart

Selective absorption

of nutrients released by digestion in small intestine and colon

precocial species

offspring have open eyes, hair and immediatly mobile

recombinants

offspring whose phenotype differs from that of the parents

sebaceous glands

oil glands

Ionic bonds

one atom strips valence electrons from another atom (high electronegativity difference), electron transfer creates ions (charged atoms)

Chloroplast

organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy

G2 phase

organelles replicate; prepare for division

source

organic compounds synthesize

detritivore

organism ingests non living matter saprotroph

consumer

organism that ingests other organic matter

Osmoregulators

organisms that maintain their internal water balance and solute concentration within narrow limits

sister chromatids

original DNA and its attached copy

cortex

outer layer of the kidney

testa

outer seed coat that protects embryo

cortex of ovary

outer, dense. contains follicles with oocytes

Serosa

outermost layer

Epidermis

outermost layer of cells in plants, especially in leaves

Muscle layer

outside the submucosa

Hardy-Weinburg Equation

p^2 + 2pq + q^2 = 1

Mitosis

part of eukaryotic cell division during which the cell nucleus divides

polar head

part of the phospholipid that is attracted to water.

integral proteins

penetrate the hydrophobic interior of the lipid bilayer

Interphase

period of the cell cycle between cell divisions

transitional phase

phase in growth curve during which population growth slows as the carrying capacity is reaches. natality falls, mortality rises Phase of population growth where the population continues to grow, but increasingly slowly as competition increases as availability of resources are reduced

plateau phase

phase in growth curve when something limits population and growth stops The population has reached the carrying capacity and population growth ceases due to limited resources. Mortality and death equal natality and Immigration

exponential phase

phase of unlimited growth of a population in an unlimited environment shown a growth curve (J-shaped curve) during which limiting factor is birth rates so population grows exponentially.

producers

photosynthetic such as plants

root uptake

plant roots absorb water and minerat ions

Xerophytes

plants adapted to arid climates

long-day plants

plants that bloom only when the period of day is longer than a specific period of darkness

short day plants

plants that flower when nights are longer than a critical length

Halophytes

plants that live in highly saline (salty) soil

Sacrolemma

plasma membrane of a muscle fiber

centromere

point at which 2 sister chromatids are attached

Fertilisation in plants

pollen (male gamete) fuses with the ovule (female gamete) inside the ovary to produce a seed

Low biotic index =

polluted

micropyle

pore in outer covering to allow water in

trophic level

position on a food chain

predation

predators feed on prey

Proestrogen

prepares the uterus for fertilization including the thickening of the endometrium.

What is the quaternary structure of a protein?

presence of multiple polypeptide chains

herbivory

primary consumers feed on plants or other producers

Endocytosis

process by which a cell takes material into the cell by infolding of the cell membrane

reabsorption

process whereby renal tubules return materials necessary to the body back into the bloodstream

nutrient cycles

processes that that move nutrients back and forth between the biotic and abiotic environment

interstitial cells

produce testosterone

Ovary

produces eggs, estrogen, and progesterone

anther

produces pollen

lactic acid

product of fermentation in many types of cells, including human muscle cells

apoptosis

programmed cell death

Histones

protein molecules around which DNA is tightly coiled in chromatin

fibrin

protein that forms the basis of a blood clot

histones

proteins associated with DNA

globular proteins

proteins that are water soluble

cyclins

proteins that control the cell cycle

Cyclins

proteins that regulate the timing of the cell cycle in eukaryotic cells

semilunar valves

pulmonary and aortic valves located between the right ventricle and the pulmonary artery and between the left ventricle and the aorta

High heat of vaporization

quantity of heat required to convert 1g from liquid to gas states (Evaporative cooling/sweat)

Fibrillation

rapid, random, and ineffective contractions of the heart

Substrate

reactant of an enzyme-catalyzed reaction

light-dependent reactions

reactions of photosynthesis that use energy from light to produce ATP and NADPH

What does a Spirometer do?

records the volume of gas expelled per breath

species evenness

relative abundance of each species

Exergonic

releases energy

DNA gyrase

relieves DNA supercoiling

What does DNA polymerase I do?

removes RNA primers and replaces them with DNA

Nucleosome

repeating subunit of chromatin fibers, consisting of DNA coiled around histones

kidney transplant

replacement of a diseased kidney with one that is supplied by a compatible donor

benign

restricted to a tissue or organ

Angiospermophytes

roots, leaves, woody or non woody stems anything with flowers, ovules in seeds

symplastic pathway

route through the cytoplasm and plasmodesmata of plant cells by which water and dissolved substances are transported.

What is a Halophyte

salt-tolerant plant

unity of type

same bones approximately same position but appear completely different

seed dispersal

scattering of seeds; can be done by animals, insects, air, or water

Krebs cycle

second stage of cellular respiration, in which pyruvate is broken down into carbon dioxide in a series of energy-extracting reactions

plasma cells

secrete antibodies

alpha cells

secrete glucagon

beta cells

secrete insulin

pineal gland

secretes melatonin

Loop of Henle

section of the nephron tubule that conserves water and minimizes the volume of urine

Annelida

segmented worms

autotropic

self-feeding

intron

sequence of DNA that is not involved in coding for a protein

fibourous proteins

sequence prevents folding and ensures chain of amino acid is elongated

cell cycle

series of events that cells go through as they grow and divide

Light Independent Reactions (Calvin Cycle)

set of reactions in photosynthesis that do not require light; energy from ATP and NADPH is used to build high-energy compounds such as sugar; also called the Calvin cycle

Gametes

sex cells

Symplesiomorphy

shared ancestral trait

Synapomorphy

shared derived character

Covalent bonds

sharing pair of valence electrons, # of electrons required to complete an atom's valence shell determines how many bonds will form

Dextrins

short chains of glucose units resulting from starch breakdown Used to thicken foods

List the purposes of carbohydrates

short terms storage, easier to digest (more rapid energy release), soluble in water (easier to transport in blood etc.), 4 calories/gram

ball and socket joint

shoulder and hip

Karyogram

shows the chromosomes of an organism in homologous pairs of decreasing length.

Homoplacy

similar due to reversal of apomorphy

homoglous structures

similar structures that related species have inherited from a common ancestor

N(N-1)/∑n(n-1)

simpson's reciprocal index of diversity

Saturated fat

single bonds between all carbons in fatty acid (i.e. saturated with hydrogen), solid at room temperature

metaphase

sister chromatids align on equator of cell

genetic equilibrium

situation in which allele frequencies remain constant

Co-dominance

situation in which both alleles of a gene contribute to the phenotype of the organism

First line of defense

skin and mucous membranes

Venules

small veins

radius bone

smaller bone in the forearm (lower arm) on the same side as the thumb

Bronchioles

smallest branches of the bronchi

follicle cells

somatic cells that surround the oocyte and nurse cells during egg development

auxin efflux pumps

specialised membrane proteins that use ATP to move auxins out of cells located closer to the light

lacteals

specialized lymph vessels in the small intestine that absorb fat into the bloodstream

dendritic cells

specialized white blood cells that patrol the body searching for antigens that produce infections

endemic species

species that are native to and found only within a limited area

endemic species

species that occurs naturally in an area

keystone species

species with a disproportionate effect on the structure of an ecological community.

Spermatoza

sperm cells

Porifera

sponges

West Nile Virus

spread to humans by the bite of an infected mosquito

Granum

stack of thylakoids

Interphase

stage in which cell performs task for which it is preprogrammed

Blastocyst

stage of early development in mammals that consists of a hollow ball of cells

high boiling point

strong intermolecular forces

Collagen

structural protein found in the skin and connective tissue

Phospholipids

structure same as fat except 2 fatty acid tails and a phosphate group attached to glycerol

List the purposes of proteins (general)

structure, transport, muscle contraction, defense, cell adhesion, tensile strengthening, DNA packaging, hormones, receptors, catalysis (enzymes), etc.

centrioles

structures from which spindle fibers arise during mitosis; found in animal cells only

antiparallel

subunits run in opposite directions

prophase

supercoiling of chromosomes; nucleolus disappears; nuclear envelope disintegrates

Sertoli cells

support spermatogenesis

pulmonary surfactant

surface active agent: secreted fluid by the alveolar cells: reduces surface tension of pulmonary fluids: contributes to the elasticity of the lung: prevents lung fillage h2o (infants)

Cell size limits

surface area to volume ratio

Anabolism

synthesis of complex molecules from simpler molecules (ex. making DNA, photosynthesis)

autotrophs..., heterotrophs...

synthesise molecules... eat others

What does the large subunit of a ribosome contain?

tRNA -APE binding sites

down regulation

target cells lose receptors in response to the hormone

transient

temporary, fleeting

Homologous

term used to refer to chromosomes that each have a corresponding chromosome from the opposite-sex parent

immunity

the ability of an organism to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells.

Realised niche

the actual conditions and resources in which a species exists due to biotic interactions.

pulmonary artery

the artery carrying blood from the right ventricle of the heart to the lungs for oxygenation.

Vitalism

the belief in a life force outside the jurisdiction of physical and chemical laws

Glycolysis

the breakdown of glucose by enzymes, releasing energy and pyruvate

corpus luteus

the broken-down follicle after the egg is released from the ovary

vasa recta

the capillary system in the kidney that serves the loop of Henle

Genome

the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes

acute myocardial infraction

the condition in which a portion of the myocardium dies as a result of oxygen starvation; often called a heart attack by laypersons

edge effect

the condition in which, at ecosystem boundaries, there is greater species diversity and biological density than there is in the heart of ecological communities.

Monophyly

the condition that a taxon or other group of organisms contains the most recent common ancestor of the group and all of its descendants

intestine

the digestive tube from stomach to anus

chorionic villus sampling

the examination of cells retrieved from the chorionic villi

urinalysis

the examination of urine to determine the presence of abnormal elements

spider silk

the fibrous protein spun by spiders for making webs, drop lines, nest building, and other uses.

intermembrane space of mitochondria

the fluid-filled space between the inner and outer mitochondrial membranes

Glucose

the form of sugar that circulates in the blood and provides the major source of energy for body tissues.

volcanic activity

the formation and eruption of volcanoes

law of independent assortment

the law that states that genes separate independently of one another in meiosis

carrying capacity

the maximum population size that can be supported by the environment due to limited resources.

Testosterone

the most important of the male sex hormones. Both males and females have it, but the additional testosterone in males stimulates the growth of the male sex organs in the fetus and the development of the male sex characteristics during puberty

active transport

the movement of materials through a cell membrane using energy

passive transport

the movement of substances across a cell membrane without the use of energy by the cell

fundamental niche

the niche that a species could potentially occupy The full range of environmental conditions and resources an organism can possibly occupy and use (when limiting factors are absent in its habitat)

species richness

the number of different species in a community

Malpighian tubule system

the organ of excretion in insects and many other arthropods consisting of narrow tubules opening into the anterior part of the hindgut.

Random orientation

the orientation of homologous chromosomes in the spindle axis during metaphase I is random and either maternal or paternal homologue may orient towards a given pole.

Plumule

the part of a plant embryo that will, when mature, become the leaves

puberty

the period of sexual maturation, during which a person becomes capable of reproducing

Ethics

the principles of right and wrong that guide an individual in making decisions

cell respiration

the process in cells in which oxygen is used to release stored energy by breaking down sugar molecules

Combustion

the process of burning something

transpiration rate

the process of givng off or exhaling water vapor through the skin or mucous membranes

gas exchange

the process of obtaining oxygen from the environment and releasing carbon dioxide

end product inhibition

the product of a reaction inhibits the enzyme required for the reaction.

Bioluminescence

the production of light by means of a chemical reaction in an organism

Oogenesis

the production, growth, and maturation of an egg, or ovum

Micropropagation

the propagation of plants by growing plantlets in tissue culture and then planting them out.

Mitotic index

the ratio between the number of cells in mitosis to the total number of cells.

hemolysis

the rupture or destruction of red blood cells.

Carbohydrates

the starches and sugars present in foods

antisense strand

the strand of DNA that runs 3' to 5' and is complementary to the sense strand. It acts as a template strand during transcription.

sense strand

the strand of DNA that runs 5' to 3' and contains the genetic code for a protein.

Epigenetics

the study of environmental influences on gene expression that occur without a DNA change

chromosome number

the sum of all chromosomes in a cell of a given type

rhodospin

the visual pigment found in rods

What is the tertiary structure of a protein?

three-dimensional shape of a polypeptide

Platelets

thrombocytes

Myofibril

tightly packed filament bundles found within skeletal muscle fibers

root hairs

tiny hair-like extensions that increase the surface area of the root allowing it to absorb more water and nutrients

Alveoli

tiny sacs of lung tissue specialized for the movement of gases between air and blood

Sequencing of DNA

to determine the order of nucleotide bases in a DNA molecule.

extend

to reach out

rotate

to spin on an axis

Biomass

total amount of living tissue within a given trophic level

Osmolarity

total concentration of all solute particles in a solution

inward

toward the inside

outward

toward the outside

acquired characteristics

traits altered by an individual organism during its life

Urethra

tube leading from the urinary bladder to the outside of the body

tracheids

tube-shaped cells that carry water and minerals up from the roots

Secondary tumours

tumours become detached and move elsewhere

What do denitrifying bacteria do?

turn NO3 back into N2 gas to be released into the atmosphere

Supercoiling

twisting in the opposite direction to the turns of the double helix during the first stage of mitosis.

Telophase

two nuclei form

quartenary structure

two or more polypeptides interact to form a functional protein

Transfer RNA

type of RNA molecule that transfers amino acids to ribosomes during protein synthesis

Amylose

unbranched starch

yeast

unicellular fungi

Autapomorphy

unique derived trait

O blood type

universal donor; no antigens present, no reaction when typing to either A or B solutions.

stem cells

unspecialized cells that are able to renew themselves for long periods of time by cell division

Atria

upper chambers of the heart

humerus bone

uppermost and largest bone of the arm

nitrogenous wastes

urea, uric acid, ammonia

single nucleotide polymorphism

variation in a DNA sequence occurring when a single nucleotide in a genome is altered

Xylem

vascular tissue that carries water upward from the roots to every part of a plant

amphibians

vertebrates that live in water and on land, smooth skin covers body, lay eggs, cold blooded

Reptiles

vertebrates that live on land, scales cover body, lay eggs, cold blooded

cortical granules

vesicles located just under the plasma membrane of an egg cell that undergo exocytosis during the cortical reaction

blood flow

volume of blood flowing through vessel, organ, or entire circulation in given period

Long Wave emissions

warm surface absorbs short wave radiation and remits long waves

apoplastic route

water and solutes move along the continuum of cell walls and extracellular spaces

eutrophication

water becomes full of nitrates and phosphates The response of aquatic ecosystems to the addition of artificial or natural nutrients through detergents, fertilizers, or sewage. Commonly an intial algal blooms is followed by a decline in dissolved oxygen

Hydrophobic

water hating

hydrophilic

water loving

Metabolism

web of all enzyme-catalyzed reactions in a cell or organism

kidney failure

when kidneys can no longer cleanse the blood and maintain homeostasis

primary succession

when life begins in area where it was completely eradicated or never existed. Ecological succession on entirely new land without any established soil (due events such as s volcanic eruptions or glacier retreat)

covergent evolution

when structures look the same and share a common function but are not derived from a common ancestor

divergent evolution

when two or more species sharing a common ancestor become more different over time

Behavioural isolation

when two populations are capable of interbreeding but have different behaviours such as courtship rituals or feeding.

spatial habitat

where a species lives. The physical environment (i.e., the chemical resources and physical conditions) of an organism or organisms

Chiasmata formation

where crossing over has occurred (2-3 times in 1 pair) criss-crossed regions called chiasmata form that hold the pair together until anaphase 1

Flagella

whiplike tails found in one-celled organisms to aid in movement

Proteins

wide range of functions, each has a complex 3-D shape (conformation), monomers are amino acids (there are 20)

Trachea

windpipe

Chloroplasts and mitochondria arose via endosymbiosis, name 5 similarities between (MADDR):

• Membranes (have a double membrane) • Antibiotics (show susceptibility) • DNA (have naked and circular DNA) • Division (occurs via a fission-like process) • Ribosomes (have 70S ribosomes)

4 Alimentary Canals (directly transfers food)

• Oesophagus - Food tract from mouth to stomach • Stomach - Storage tank with low pH (protein digestion) • Small intestine - Site of nutrient absorption • Large intestine - Absorbs water and dissolved minerals

4 Accessory Organs (supports digestive processes)

• Salivary glands - Moistens food bolus (starch digestion) • Pancreas - Secretes key enzymes into small intestine • Liver - Metabolises absorbed nutrients (produces bile) • Gall bladder - Stores and secretes bile (emulsifies fats)

Small SA:Vol Ratio means 3 things:

⇧ metabolic rate ⇩ material exchange Low survival chances

High specific heat

(Amount of heat absorbed)/(amount of heat lost/change temperature by 1°C) (1 cal)/(g/°C)

What 5 things to antibodies promote when aiding in pathogen destruction?

(PANIC) Phagocyte recrutment, agglutination, neutralisation, inflammation and complement activation

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

Haploid

(genetics) an organism or cell having only one complete set of chromosomes

Diploid

(genetics) an organism or cell having two sets of chromosomes or twice the haploid number

Translation

(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm

Bacteria

(microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission

Capture-Mark-Release-Recapture/Lincoln Index calculation

(number collected in 1st capture × number collected in 2nd capture) ÷ number marked in 2nd capture

Chi squared formula

(observed-expected)^2/expected

Biotic index calculation

(tolerance of individual x tolerance of species)/total number of individuals

Explain the process of translation

* consists of initiation, elongation and termination * mRNA translated in a 5' to 3' direction * binding of ribosome to mRNA * small sub-unit then large * first/ initiator tRNA binds to start codon/ to small subunit of ribosome * AUG is the start codon * second tRNA binds to ribosome * large subunit moves down mRNA after a second tRNA binds * amino acid/ polypeptide on first tRNA is transferred/ bonded to amino acid on second tRNA * peptide bonds between amino acids/ peptidyl transferase * requires GTP * movement of ribosome/ small subunit of ribosome down the mRNA * loss of tRNA and new tRNA binds * reach a stop codon/ termination * polypeptide released * tRNA activating enzymes link correct amino acid to each tRNA * (activated) tRNA has an anticodon and the corresponding amino acid attached

Cillia

*Tiny hairlike extensions* that move together in a sweeping motion

Outline the roles of the different binding sites for tRNA on ribosomes during translation (4)

- A, P and E binding sites are on the large subunit of the ribosome - initiation of translation starts with binding of met-tRNA to the start codon - large subunit binds with start tRNA in the P site - A binding site holds the tRNA with the next amino acid to be added - peptide bonds formed between a a in A site and polypeptide at P site - polypeptide transferred to the tRNA in A site - the tRNA with polypeptide in A site then moves to P site - E binding site exit is where the tRNA from P site without a a leaves the ribosome

Compare competitive inhibition and non-competitive inhibition. (5)

- CI substrate and inhibitor are chemically similar, NCI not - CI inhibitor binds to active site, NCI allosteric site - CI inhibitor doesnt change shape of active site, NCI inhibitor does - CI increase in substrate concentration reduces the inhibition, NCI increase in substrate concentration doesnt - both reduce enzyme activity - bith bind to enzyme - both prevent substrate from binding to active site - e.g . CI succinate dehydrogenase is inhibited by malonate, NCI pyruvate kinase is inhibited by alanine

Describe what happens in Prophase.

- Chromatin condense into two sister chromosomes (from supercoiling) -The Nuclear envelope begins to break down and disintegrate - Microtubules that form the mitotic spindle begin to develop from centromeres in cell -Centrosomes move towards the poles and the spindle fibers form between them. (Logest phase)

Explain how DNA is used to pass on genetic information to offspring accurately but also produce variation in species (8)

- DNA is replicated semi-conservatively - mutations can be a source of variation - mutations in the DNA may not result in changes in the amino acid for which the triplet codes - genetic code is redundant - genes occur as paired alleles which can be different - crossing-over occurs - recombines linked alleles producing new combinations - random orientation of bivalents - large genetic variation in gametes / 2^23 - random recombination of alleles during fertilization - different phenotypes among members of the same population - natural selection may lead to enhanced survival of recombinants

Explain the methods and aims of DNA profiling (8)

- DNA sample obtained - from blood - DNA amplified by PCR - satellite DNA used - DNA cut into fragments - using restriction endonucleases - gel electrophoresis used to separate DNA fragments - where fragments are separated by size - number of repeats varies between individuals - forensic use - DNA obtained from crime scene to compare - paternity testing - to identify biological father - genetic screening - presence of particulat bands correlates with probability of certain allele

Explain how males inherit hemophelia and how females can become carriers for the condition (8)

- H is due to a reccessive allel - X^h is a hemophilia allele - H is sex-linked - allele is on the sex chromosome - sex chromosomes in females are XX and XY in males - Y chromosomes dont have the H allele/ H males are H^hY - males inherit their X chromosome from their mother - males have only one copy so recessive trait - males have a 50% chance of H if mother is carrier - carrier is a heteroxygous for gene / XHXh - dominant allele masks the recessive allele - females inherit one X chromosome from father and one from mother - affected H males have carrier daughters - H allele could be inherited from either parent

Explain the processes involved in the Krebs cycle (8)

- Krebs cycle only occurs in aerobic conditions - the Krebs cycle occurs in the mitochondria - acetyl CoA from link rxion releases an acetyl group - NADH + H+ and CO2 forced with each decarboxylation - decarboxylation involves oxidative decarboxylation and the release of energy - acetyl group is joined to a 4-carbon molecule to form a 6C molecule - 6C molecule to 5C molecule - then converted to original 4C molecule and cycle repeats - one molecule of ATP made during this ste p - reduced NADH and FADH2 and carbon dioxide are end-products of Krebs cycle

Explain how chemical energy for use in the cell is generated by ET and chemiosmosis (8)

- NAD is reduced by gaining 2 H atoms - reduced NAD produced in glycolysis/link rxion/Krebs cycle - reduced NAD delivers electrons to ETC - ETC is in cristae - electrons release energy as they flow along the chain - electrons from ETC accepted by oxygen is the final electron acceptor - proteins in the inner mit. membrane act as proton pumps - protons pumped into intermembrane space - energy from electrons used to pump protons into intermembrane space - ATP synthase in cristae - energy released as protons pass down the gradient/ through ATP synthase - ATP synthase converts ADP to ATP - oxidative phosphorylation is ATP production using energy from oxidising foods

Distinguish between prokaryotic and eukaryotic cells. (6)

- P naked DNA, E protein associated with DNA - P DNA in cytoplasm, E DNA in nucleus - P circular DNA, E linear chromosomes - P has no mitochondria, E mitochondria - P 70s rib, E 80S rib - P no membrane bound organelles, E internal membranes from organelles - P pili present, Eu no pili - P plasmids present, E none - P cell wall present, E cell wall only present in plants - P solid flagella, E flagella flexible/membrane bound

compare the genetic material of eukaryotes and prokaryotes (6)

- Pr DNA circular whereas Eu linear - Pr DNA one chromosome whereas Eu many chromosomes - Pr not associated with proteins whereas E associated - P has plasmids present, E doesnt - P has no introns, E has introns and exons - P DNA found in nucleoid region , E DNA contained in nucleus - P DNA has one replication point, E has many - mitochondrial and chloropast DNA similar to prokaryotic DNA - both use DNA as their genetic material.

Outline the structure of a ribosome (4)

- Ribosome composed of two halves, a large + small subunit. - During translation; ribosomal subunits assemble together like a sandwhich on the strand of mRNA. - Each subunit composed of RNA molecules + Proteins. - three tRNA binding sites - Small subunit binds to mRNA. - The large subunit has binding sites for the tRNA's + also catalyzes peptide bonds between amino acids.

Bony ray-finned fish

- Scales grow from the skin - Gills with a single gill slit - Fins supported by rays - Swim bladder (for buoyancy) - External fertilization

Discuss the ehtical issues of therapeutic cloning in humans (8)

- TC is the creaion of an embryo to supply embryonic stem cells for medical use - transfer of nucles from somatic cell into an anucleated egg - stimulated by shock to begin cell division - stem cells from embryo have greater flexibility - pluripotent cells can give rise to all cells in the body - no danger of rejection of transplant because DNA matches - elimination of pain - would eliminate organ and tissue shortages - no need for immunosuppressive drugs - manipulation of human embryos not ethically acceptable - the process of extracting stem cells involves killing the embryo - many attempts before success is attained

Distinguish between autosomes and sex chromosomes in humans (4)

- X and Y chromosomes determine sex - females XX and males XY - X chromosome is larger than Y chromosome - 22 pairs of autosomes - males and females have same type of autosomes

Outline a technique of gene transfer resulting in genetically modified organisms (5)

- a gene transfer takes a gene from one organism and inserts it into another - using plasmid impregnation - use of reverse transcriptase to obtain gene from mRNA - endonuclease used to excise gene - restriction enzyme used to cut open plasmid - sticky ends used to link gene to plasmid - DNA ligase used to seal nicks - bacterium takes in plasmid - clone the recombinant - e.g. maize crops modified - makes corn resistant to pest - producing higher crop yields - less land needed for crops - less pesticide needed - beneficial insects might be harmed - gene might spread to other plants by cross pollination - allergic reactions in humans - only favoured countries have tech/ increases inequality

Describe how water is carried by the transpiration stream (7)

- active transport of solutes from soil into roots - draws water by osmosis - root hairs provide large surface area for water uptake -transpiration is water loss from plant by evaporation - flow of water through xylem from roots to leaves is he transpiration stream - evaporation from spongy mesophyll cells - replaced by osmosis from xylem - diffusion of water vapour through stomata - water lost replaced from xylem - xylem through cells to air space - water pulled out of xylem creates suction - transpiration pull results - water molecules are cohesive - due to hydrogen bonding - xylem vessels are thin hollow tubes - adhesion between water and xylem due to polarity of water molecules - creates transpiration stream

Describe the action of the heart in pumping blood (5)

- both atria collect blood from veins - SA node sends impulses to muscle fibres initiating contraction - blood is pushed to ventricles by contraction atria - AV valves are open as atria contract - semilunar valves are closed so that ventricles fill with blood - ventricles contract / ventricular systole - AV valves close - blood is pushed through the semilunar valves/ pulmonary artery and aorta - when ventricles relax / diastole, semilunar valves close preventing backflow of blood. simultaneous contraction

Distinguish between aerobic and anaerobic respiration (5)

- cell respiration is the controlled release of energy from organic compounds to form ATP - Ae requires oxygen, An doesnt - Ae in cytoplasm and mitochondrion, An in cytoplasm - Ae Oxygen reduced, An pyruvate reduced - Ae high yield of ATP, An low yield of ATP - Ae high yield of NADH, An low yield - Ae end product co2 and h2o, an end products ethanol and co2 - ae can use fats and proteins, an can only use sugars - Ae involves oxidative phosphorylation/ETC, An doesnt - Ae involves Krebs cycle, An doesnt

Describe the process of blood clotting (4)

- clotting factor released by platelets - cascade of reactions - prothrombin activated to thrombin - thrombin converts soluble fibrinogen to insoluble fibrin - mesh of fibrin seals wound by trapping platelets

Outline the outcomes of the human genome project (4)

- complete human DNA sequenced - identification of all human genes - protein structures/functions - find evidence for evolutionary relationships - find mutations - find genes causing disease - develop new drugs based on base sequence - tailor medication to individual genetic variation - promote international co-operation

Describe the importance of hydrolysis in digestion (6)

- digestion is the breakdown of large molecules into smaller ones - to allow diffusion - so foods can be absorbed into the bloodstream - so food can move from bloodstream into cells - small molecules can be joined to make macromolecules - hydrolysis is aided by enzymes - hydrolysis required water - polysaccharide to disacchardie/mono - polypeptides hydrolised to a.a. - triglycerides hydrolised to fatty acids and glycerol

Explain how circulation of the blood to the lungs and to other systems is separated in humans and what the advantages of this separation are (8)

- double circulation - heart is a double pump - deoxyg blood pumped to lungs and ox tothe rest of the body - ech side of the heart has A and V - LV pumps blood to tissues amd RV pumps blood to the lungs - LA receives blood from the lungs and RA receives blood from tissues - LV pumps blood via the aorta and RV pumps blood via the pulm artery - LA receives lood via the pulm vein and RA receives blood via the vena cava - lungs require low pressur eblood - high pressure required to pump blood to all systems but lungs - pressure of blood returning from lungs not high enough to continue to tissue - ox and deox blood kept separated

Describe the lock and key model and how the induced fit model extends it (6)

- enzymes are globular proteins that are catalysts lock and key model - explains specificity of enzyme-substrate - the substrate has complementary shape to the active site of the enzyme - the active site can be changed by different chemicals /temperature/pH so substrate cannot bind induced-fit model - changes in the active site allow substrate to bind - the substrate induces the active site to change - bonds weakened in the substrate - explain reduction of activation energy

distinguish between fibrous and globular proteins + examples (6)

- fibrous proteins are sheets whereas globular are round - fibrous are insoluble, whereas globular soluble - globular proteins more sensitive to changes in pH/temp/ than fibrous - fibrous proteins have structural roles - globular proteins used for catalysis - fibrous; collagen - globular; insulin

Explain how flowering is controlled in long day and short day plants, including the role of phytochrome (7)

- flowering affected by light - phytochrome - exists in two forms - Pr converted to Pfr in red or day light - sunlight contains more red than far red light so Pfr predominates during the day - gradual reversion of Pfr to Pr occurs in darkness - Pfr is active form - in long-day plants, flowering induced by dark periods shorter than a critical length - enough Pfr remains in long-day plants at end of short nights to stimulate flowering - Pfr acts as promoter of flowering in long-day plants - short-day plants induced to flower by dark periods longer than a critical length - at end of long nights enough Pfr has been converted to Pr to allow flowering to occur - Pfr acts as inhibitor of flowering in short-day plants

Describe the process of peat formation (4)

- formed from dead plant material - formed in waterlogged soils - where saprotrophs not active - so organic matter not fully decomposed - occurs in acidic conditions - occurs in anaerobic conditions - very slow process

outline the structure and function of nucleosomes (4)

- found in euk - consists of DNA wrapped around histone proteins - histones are in group of 8 - are held together by another histone - in linker region - help to supercoil chromosomes - regulate transcription/gene expression

Outline how and where energy is stored in plants (4)

- glucose stored as starch - starch stored in chloroplast - starch stored in seeds - stored as lipids - in seeds - lipids store twice as much energy per gram as starch

Explain anaerobic respiration

- glucose transformed into 2 molecules of pyruvate - smaller amount of ATP produced than in aerobic - oxidation reactions using NAD producing NADH - NAD regenerated by reducing pyruvate - pyruvate to CO2 and ethanol in yeast - pyruvate to lactic acid in humans

Explain how the rate at which the heart beats is controlled (6)

- heart cells can contract on their own (myogenic) - contractions controlled sinoatrial node - sinoatrial node is in the wall of the RA - signal to contract transmitted from across the atria - nerve impulses from medulla to the heart - fone nerve increases rate and another nerve decreases it - epinephrine increase rate

Describe four properties of water that are due to H bonding and polarity (4)

- high s.h.c. requiring large amounts of energy to break the H-bonds - high b.p as .H bonds must be broken to change from liquid to gas - cooling effect of evaporation due to H bonds taking energy from liquid water to break/ high latent hear of evaporation - water molecules on surface resistant to forces because of surface tension - polarity causes water molecules to stick together through cohesion - water molecules stick to other polar molecules through adhesion - good solvent for polar organic molecules

Outline the effects of putting plant tissue in hypertonic solution (4)

- hypertonic solution has a higher solute concentration that the cell - water moves out of the cells by osmosis into the hypertonic solution - water moves from lower solute concentration to higher solute concentration - pressure inside cell drops - volume of cytoplasm drops

Describe the functioning of immunoglobulins (3)

- immunoglobulins function as antibodies - variety of binding sites - specific to antigens on pathogens - constant region aids destruction of path - attracts phag to engulf path - bursting path cells

Describe the codominance of multiple alleles using inheritance of ABO blood groups as an example of them (6)

- in multiple alleles there are more than 2 alleles of a gene - codominant alleles both affect the phenotype - Ia and Ib an i are the three alleles controlling blood groups - in ABO bblood group Ia and Ib are codominant and i is recessive - when A and B are both present, both are expressed - i is recessive to both Ia and Ib - only homozygous ii organisms are blood group O

Outline the relationship between Mendel's law of independent assortment and meiosis (6)

- independent assortment of unlinked genes - genes are inherited independently - unlinked genes are on different chromosomes - presence of one allele does not influence presence of other allele - evidence from dihybrid crosses - all allele combos - from gametes - ration of 9:3;3;1 in double heterozygote cross - 9;3;3;1 ratio shows equal probability of all gametes - orientation of bivalents is random - orientation of one bivalent doesnt affect orientation of others - in metaphase I

Outline the positions and functions of proteins in membranes. (8)

- integral proteins are embedded in the membrane - peripheral proteins are on the surface of the membrane - some integral proteins extend from one side of the membrane to the other - hormone binding sites - e.g. insulin - enzymes - e.g. sucrase - cell adhesion - cell-to-cell communication recognition - contact inhibition - channels for passive transport/facilitated diffusion - carrier proteins for active transport - receptors for neurotransmitters - such as acetylcholine - electron carriers - e.g. ETC of of cellular respiration - pigments

explain the use of karyotyping in human genetics (8)

- karyotype is the number and type of chromosomes in a cell - cells collected by amniocentesis - cells stimulated to divide and reach metaphase - burst cells and spread chromosomes - chromosomes are arranged in pairs - according to size - karyotypes used to identify sex - male is XY and female XX - used to identify chromosome mutations - such as DS due to extra chromosome 21 - used for pre-natal diagnosis of chromosome abnormalities - may lead to a decision about the fetus - prepare for consequences of abnormality in offspring

Discuss the use of lactase in the production of lactose free milk (8)

- lactose is a disaccharide - lactase digests lactose into glucose and galactose - lactase produced naturally by yeast - biotech. companies isolate lactase for use in food processing - lactase can be added to milk to reduce the level of lactose in milk - or lactase can become an immobilized enzyme - lactose intolerant ppl cannot drink milk - glucose and galactose are sweeter than lactose - so less sugar needed in food production from milk - bacteria ferment glucose and galactose more quickly than lactose, so production dairy products is faster - galactose and glucose are more soluble and so improve texture of ice cream

Describe the features of alveoli that adapt them to gas exchange (6)

- large surface area from having many alveoli - single layer of thin cells in wall - surrounded by dense network of capillaries - short distance for gases to diffuse - moist lining of moisture on inside of alveolus - moisture allows gases to dissolve - diffusion of oxygen down concentration gradient

Explain how the distribution of tissues in the leaf of a dycotyledonous plant is adapted to production and distribution of products of photosynthesis (8)

- leaf has a large surface area for absorption of light - upper epidermis allows light to pass - waxy cuticle to prevent water loss - palisade mesophyll contains many chloroplasts - palisade mesophyll close to upper layer to receive more light - spongy mesophyll contains chloroplasts which allow photosynthesis - spongy mesophyll allows gaseous exchange - stoma allow co2 for photosynthesis to diffuse in - stoma allow o2 produced in photosynthesis to diffuse out - xylem brings water - phloem carries away products of photosynthesis - guard cells open and close stoma

Explain how abiotic factors affect the rate of transpiration in a terrestrial plant. (8)

- less transpiration as humidity rises - air spaces inside leaf are saturated with water vapur - smaller concentration gradient with higher atmospheric humidity - more transpiration as temperature rises - faster diffusion - faster evaporation - more transpiration as wind speed increases - water vapour blown away from the leaf - increasing the concentration gradient - more transpiration in the light - light causes stomata to open - low co2 concentration inside leaf in bright light so stomata open wider

explain the control of gene expression in eukaryotes (8)

- mRNA conveys genetic info from DNA to the ribosomes where it guides polypeptide production - gene expression requires the production of specific mRNA - most genes are turned off - some genes are only expressed in certain cells - transcription factors can increase/decrease transcription - chemical environment of a cell can affect gene expression. - transcription factors may prevent or enhance the binding of RNA pol - nucleosomes limit access of transcription factors to DNA - DNA methylation appears to control gene expression - some methylation gene patterns are inherited - introns may contain positive or negative gene regulators

Explain the processes that result in genetic variation in the sperm produced by an adult male (5)

- meiosis - independent assortment as chromosomes move to opposite poles - random orientation in M1 - in M1 - 2^23 possible combinations - crossing over/recombination of linked genes - during P1 - can occur anywhere along a chromosome - random orientation of chromatids - gene mutations may occur

outline three processes required for successful sexual reproduction in plants (3)

- meiosis - pollination - fertilisation happens after pollination - seed dispersal

Outline the control of metabolic pathways (6)

- metabolic pathways can be a sequence of reactions - they can be cycles of reactions - different enzymes control each reaction in the sequence - accumulation of an end-product can inhibit the first enzyme of the sequence - an end product inhibitor joins an allosteric site - attachment to the allosteric site changes shape of active site - preventing the binding of a substrate - until the level of the end-product is reduced - this is an example of negative fb

Distinguish between anabolism, catabolism and metabolism (3)

- metabolism is all enzyme-catalyzed rxions and is anabolism plus catabolism - anabolism is synthesis or larger molecules from smaller monomers - catabolism is breaking down complex molecules into smaller monomers

Describe the origin of eukaryotic cells according to the endosymbiotic theory (4)

- mitochondria and chloroplasts are similar to prok - host cell took in another cell by endo - but did not digest - chl and mit were once independent - DNA loop in chl/mit - binary fission of chl/mit - double membrane around chl/mit - 70S rib in mit/chl

outline the cell cycle (4)

- mitosis is the division of a nucleus to produce two genetically identical daughter nuclei - consists of pmat - cytokinesis occurs after mitosis - interphase is the metabolically active phase between cell divisions the interphase consists of S, G1 and g2 - DNA replicates in the S phase - cell growth/prep for mit/duplication of organelles in G1 and G2

types of carbohydrates found in living organisms (4)

- mono-, di- anf poly- saccharides consist of one, two or many units - mono : glucose - disaccharide: lactose - poly: starch/glycogen/cellulose

Describe the consequences of the potential overproduction of offsprings (5)

- more offspring than the environment can support / carrying capacity reached - increased mortality - competition for resources - such as food shortages - variation between members of population - better adapted are more likely to survive - better adapted reproduce and pass on favourable traits - natural selection leads to evolution

Explain how polar and non-polar amino acids help channel proteins and enzymes carry out their functions (5)

- non-polar amino acids cause channel proteins to embed in a membrane - polar amino acids at either end cause channel proteins to be transmembrane - polar amino acids lining pore allow polar partivles to pass through - polar a.a. on surface of enzyme allow it to dissolve in water - polar and non-polar a a contribute to the specificity of the enzyme - non-polar a a of surface of enzyme allow it to embded in a membrane - polar a a at active site of enzyme attract polar substrates - positively charged a a attracte negatively charged substrate - non-polar a a at active site attract non-polar substrate

Explain the process of DNA replication (8)

- occurs during S phase of interphase - DNA replication is semi-conservative - helicase unwinds double helix - hydrogen bonds between two strands are broken - each strand of parent DNA used as template - deoxynucleoside triphosphate provides energy - synthesis continuous on leading strand and not on lagging - resulting in formation of Okazaki fragments - synthesis occurs in 5' to 3' direction - RNA primer synthesised on parent DNA using RNA primase - DNA pol III adds nucleotides - via complementary base pairing - adenine pairs with thymine and cytosine pairs with guanine - DNA pol I removes the RNA primers and replaces them with DNA - DNA ligase joins Okazaki fragments

Explain how chemiosmosis assists in ATP production during oxidative phosphorylation (9)

- occurs during aerobic respiration - oxidative phosphorylation occurs during the ETC - electrons are passed between carriers - releasing energy - finally join with oxygen to produce water - occurs in cristae of mitochondria - chemiosmosis is the movement of H ions - protons morve against concentration gradient - into the space between the 2 membranes - protons flow back to the matrix - through the ATP synthase - energy is released which produces more ATP

Distinguish between active and passive movements of materials across plasma membranes using named examples (4)

- passive includes diffusion , active includes active transport - passive includes osmosis, active includes exocytosis - passive doesnt require energy, active does - passive is down conc gradient. active is against - passive doesnt need protein pumps, active does - passive includes oxygen across alveoli, active includes glucose absorption in ileum

describe the transport of organic compounds in vascular plants (4)

- phloem transports organic compounds - from sources to where used - through sieve tubes with sieve plates - loading of organic compounds into H+ ions out of sieve tubes by active transport - high solute concentration causes water to enter by osmosis - high pressure causes flow - companion cells help with loading - translocation

Explain the processes by which minerals are absorbed from the soil into roots (8)

- plants absorb minerals in the form of mineral ions - minerals bound to soil particles - minerals dissolve in water - mass flow causes movement of minerals with movement of water through soil - such as nitrate/phosphate/potassium - minerals can be absorbed by facilitated diffusion - diffusion is the movement of ions from high to low concentration - root hair cells provide large surface area for absorption - root hairs have many mitochondria to provide energy for active transport - fungal hyphae help to absorb minerals - minerals absorbed by active transport - as mineral ion concentration is smaller outside the root than inside - active transport requires energy - occurs through carrier proteins - proton pump transports hydrogen ions out of cell

Outline the roles of living organisms in the carbon cycle. (8)

- plants use carbon in photosynthesis - carbon compounds produced from photosynthesis - plants eaten by primary consumers - primary consumers eaten by secondary consumers - carbon compounds digested and absorbed by consumer - co2 released by cell respiration - plants/animals die and decomposed by saprotrophic bacteria - co2 released by cell respiration in bacteria - enzymes released to digest carbon compounds in organic matter - combustion releases co2 - burning fossil fuels releases co2 into atmosphere

Describe the process of endocytosis (5)

- plasma membrane engulfs solid particles of molecules - fluidity of membrane allows endocytosis - plasma membrane invaginates - membrane pinches off and edges fuse - vesicle formed - inside of plasma membrane becomes outside of vesicle membrane - vesicle breaks away from plasma membrane/moves into cytoplasm - active process/ endocytosis requires energy

Outline the processes that occur during the first division of meiosis (6)

- pmat - chromosome number halved - homologous chomosomes form bivalents in p - crossing over btwn non-sister chromatids - nuclear envelope breaks down at end of P/start of M - bivalents move to equater on metaphase plate in M - attachment of spindle fibres to centromeres chromosomes separate in A - nuclear envelope reforms in T

Outline the four levels of protein structure (4)

- primary structure is the sequence of amino acids in a polypeptide chain - secondary structures are regularly repeating structures / b pleated sheet/ alpha helics/ held together by H bonds - tertiary structure is the specific three dimensional structure of the polypeptide (held by H bonds/ hydrophobic interactions/disulfide bridges/interactions between R groups) - quaternary structure links two or more polypeptides and describes non protein groups associated with the polypeptide

Describe what is shown in pyramids of energy (6)

- pyramid of energy shows the flow of energy from one trophic energy to another in a community - units of pyramids of energy are energy per unit time - bar width is proportional to the energy stored in that trophic level - lowest trophic level is the producers - second level is primary consumer/ herbivore - third level of secondary consumer / carnivore - only a small amount of energy of one level passed to the next - bar width decreases proportionally as you go up each level - pyramid shows that there is a limit to the length of food chain

Describe respiration (8)

- pyruvate decarboxylated and reduction of NAD forms NADH + H+ - acetyl group reacts with reduced coenzyme to form acetyl CoA - acetyl CoA enters Krebs cycle - 2CO2 molecules removed as waste - energy rich NADH + H+/ FADH2 formed - for each pyruvate, 3 NADH + H+ and FADH2 formed - 1 ATP formed per pyruvate each turn by substrate-level phosphorylation - reduced NAD and FADH2 eneter electron transport chain - oxidative phosphorylation uses energy released by ETC to synthesise ATP - as electrons move alone ETC, protons move into intermembrane space - creates H+ gradient across membrane - ATP synthesised by flow of H+ back across membrane through ATP synthase - ATP synthesised by chemiosmosis - ETC reduces oxygen forming water

Explain aerobic respiration

- pyruvate fully oxidised - by the link reaction and Krebs cycle - NADH passes electrons to ETC - proton gradient generated - oxygen required as terminal electron acceptor - proton gradient used by ATP synthase to produce ATP

Explain the process of aerobic cell respiration after glycolysis has occurred (8)

- pyruvate produced by glycolysis - pyruvate enters mitochondria - pyruvate loses CO2 in link reaction - and NADH + H+ - with formation of acetyl coA - to take part in Krebs cycle - where 2 CO2 are produced - 1 ATP from ADP + Pi - along with 3 NADH + H+ - NADH + H+ provide electrons circulating in the ETC on the inner mitochondrial membrane - allowing H+ to accumulate in the intermembrane space - and come back to the matric through ATP synthase by chemiosmosi - presence of O2 required as the final electron acceptro for the ETC - producing water with H+

Explain how an impulse passes along the axon of a neuron (8)

- resting potential is -70 mV - sodium potassium pumps maintain resting potential - more sodium ions outside that inside when at resting potential - more potassim ions inside than outside when at r.p. - nerve impulse is an action potential that stimulates depolarisation alon the axon - if neuron is stimulated and threshold potential is reached, sodium ion channels open - sodium ions move in causing depolarisation - potassium ion channels open / K ions diffuse out - K+ moving out causes repolarisation

Describe how human skin colour is determined genetically (5)

- skin colour is example of polygenic inheritance - more than two genes contribute to a person's skin colour - due to the amount of melanin in skin - combination of alleles determines phenotype - allows for range of skin colours - phenotypes dont follow simple Mendelian ratios of dominance and recessiveness - the environment also affects gene expression of skin colour/ UV stimulates melanin production - the more recessive alleles there are, the lighter the skin colour

Describe the characteristics of stem cells that make them potentially useful in Medicine (5)

- stem cells retain the capacity to divide - can be used to produce large numbers of identical cells - can be used to repair damaged cells - undifferentiated - can differentiate into any cell type - can be used to form a variety of differnt tissues - used in medical research - used in treatment of leukemia

State the role of 4 named minerals needed by living organisms (4)

- sulfur: part of a.a. - calcium: strengthening bones - phosphorus - formation of nucleic acids/phospholipids - iron - formation of hemoglobin - sodium - sodium-potassium pump - potassium: sodium-potassium pump - magnesium - part of chlorophyll molecule

Explain the principles of synaptic transmission (8)

- synapse is a gap between adjacent neurons - arriving action potential depolarises pre-synaptic membrane - opens voltage-gated calcium channels in membrane - causes influx of calcium ions - causes synaptic vesicles to fuse with pre-synaptic membrane - vesicles release neurotransmitter into synaptic cleft - neurotransmitter moves across synaptic cleft - neurotransmitter binds to receptors on post-synaptic membrane - open channels allowing sodium ions/potassium ions to diffuse - initiation of action potential/depolarization in post-synaptic membrane - breakdown of neurotransmitter stops effect on post-synaptic membrane

Outline how enzymes catalyse reactions. (7)

- they increase rate of reaction; - remains unused/unchanged at the end of the reaction; - lower activation energy; - activation energy is energy needed to overcome energy barrier that prevents reaction; - annotated graph showing reaction with and without enzyme; - substrate joins with enzyme at active site; - to form enzyme-substrate complex; - active site/enzyme specific for a particular substrate; - when enzyme binds with substrate, it brings reactants closer together to facilitate chemical reactions; - induced fit model / change in enzyme conformation (when enzyme-substrate complex forms); makes the substrate more reactive.

Explain the principles of vaccination (8)

- vaccines contain a weakened form of the pathogen - vaccine introduced to the body by injection - antigens in the vaccine cause antibody production - antigen engulfed by macrophage/phagocyte - each type of lympocyte recognises specific antigen - macrophages activate helper t-cells which activate B-cells - B-cells divide to form memory cells - B-cells divide to form plasma cells/ antibody producing cells - result is immunity - first vaccination causes slow production of antibodies and lower level of antibodies - contact with the disease leads to rapid production and higher level of antibodies - booster shot stimulates memory cells/ more production of antibodies

explain the mechanism of ventilation in the human lungs (8)

- ventilation is movement of air into and out of lungs - air flows from higher to lower pressure until pressures are equal During inspiration - external intercostal muscles contract so ribcage moves up and out - diaphragm contracts so moves down - internal intercostal muscles relax - volume of lungs increases - pressure in lungs decreases During expiration - external intercostal muscles relax so ribcage moves down - recoil of elastic fibres that stretched during inspiration - internal intercostal muscles contract - abdomen muscles contract

Outline, with an example, the process of exocytosis. 5 marks

- vesicles carry materials to plasma membrane - vesicles fuses with membrane - by joining of phospholipid bilayers - aided by the fluidity of the membrane - materials released/expelled from the cell - membrane flattens - e.g. exocytosis of neurotransmitter - hormone secretion - hormones released from one cell have an effect on another

Explain the conditions needed for the germination of a typical seed (5)

- water needed to rehydrate the seed - gibberellin released - gibberellin needed to produce amylase - water needed to allow substances inside seedling to be transported - oxygen needed for cell respiration - warmth needed to speed up metabolism - warmth indicates that it is favourable season for germination - some seeds need a cold period to stimulate germination - some seeds need fire to stimulate germination - some seeds need to pass through gut of animal to stimulate germination

What happens in Cytokines

-Cytokinesis is the process of cytoplasmic division, whereby the cell splits into two identical daughter cells -Cytokinesis occurs concurrently with the final stage of mitosis (telophase) and is different in plant and animal cells

What is the difference of cytokinesis in Animal and Plant cells?

-In animal cells, cytokinesis results when a fiber ring composed of a protein called actin around the center of the cell contracts pinching the cell into two daughter cells, each with one nucleus - In plant cells, the rigid wall requires that a cell plate be synthesized between the two daughter cells.

What are some substances that are transported in blood?

-NaCl: dissolved in plasma (ions) -amino acids: dissolved in plasma (sufficient solubility due to charged regions) -glucose: dissolved in plasma (polar) -oxygen gas: carried by hemoglobin (nonpolar) -fats: transported in lipoprotein complexes (nonpolar) -cholesterol: transported in lipoprotein complexes (nonpolar) HDL and LDL

Describe what happens in Telophase

-Nuclear membrane now begin to form around each set of chromosomes -Chromosomes begin to uncoil to form chromatin again Spindle fibers break down and nuclei reform in each nuclei

Describe what happens in Anaphase

-Pairs of sister chromatids are pulled apart by spindle fibers towards the poles -Chromatids are now considered chromosomes -Chromosomes move to the poles as result of the microtubule being shortened - Cell now has two genetically identical nuclei at each end of the cell (Shortest phase)

Explain the process of transcription

-RNA polymerase - binds to a promoter on the DNA - unwinding the DNA strands - binding nucleoside triphosphates - to the antisense strand of the DNA - as it moves along in a 5' to 3' direction - using complementary base pairing - losing two phosphates to gain the required energy - until a terminator signal is reached - RNA detaches from the template and DNA rewinds - RNA pol detaches from the DNA - many RNA polymerases can follow each other - introns have to be removed in euk to from mature mRNA

Give examples of functions of specific proteins

-Rubisco=carbon fixation during photosynthesis -Insulin=hormone that regulates blood sugar by signaling glucose uptake by cells -Immunoglobulins (antibodies)=specific immunity -Rhodopsin=pigment that absorbs light in rod cells of retina -Collagen=forms strong mesh of fibers in body (skin, blood, vessel walls, ligaments, bones, etc.) -Spider silk=strong fibers for forming webs

Describe what happens in Metaphase

-Spindle Fibers are attached to the centromeres of the chromosomes -Chromosomes move towards the equator of the cell and line up -Other ends of microtubules of the spindle are attached to poles of the cell

anti-histamines

-These drugs are primarily H1 receptor antagonists. They prevent allergic reactions, reduce nausea and may increase sedation. Benadryl (diphenhydramine), Claritin (loratadine), Antivert (meclizine)

What is the purpose of Mitosis

-Tissue repair / replacement - damaged or aged cells replaced with identical healthy ones -Organismal growth - multicellular organisms derive new cells via mitosis -Asexual reproduction - vegetative propagation in plants occurs via mitotic division -Development (of embryos) - zygotes undergo mitosis and differentiate to become embryos

Distinguish between unique and highly repetitive sequences in nuclear DNA (5)

-US occur once in genome and many time in HRS -US has long base sequences and HRS has short sequences -US may be genes, HRS not genes - US may be translated, HRS never translated - US have small differences between individuals, HRS can vary greatly - exons are US, introns may be RS -US are smaller proportion of genome, HRS are higher proportion of genome - satellite DNA is repetitive -repetitive sequences are used for profiling - prokaryotes dont usually contain RS

Explain the role of auxin in phototropism

-auxin is a plant hormone -produced by the tip of the stem -causes transport of hydrogen ions from cytoplasm to cell wall - decrease in pH - makes cell call felxible -auxin makes cells grow -gene expression also altered by auxin to promote cell growth - phototropism is growth towards light -auxin moved to side of stem with least light -causes cells to grow on darker side

Explain the causes of sickle cell anemia (8)

-caused by gene mutation - due to base substitution - changes the code in the DNA - which leads to a change in mRNA - mRNA changes from GAG to GUG - which leads to a change in translation - the tRNA adds the wrong a.a. to the polypeptide chain - glutamic acid replaced by valine - produces abnormal hemoglobin - causing abnormal red blood cells/ sickle shaped -lowers the ability to transport oxygen - sickle cell allele is co-dominant - carriers are more resistant to malaria (Hb^s Hb^a)

Outline the formation of chiasmata during crossing over (5)

-chiasmata formed during P1 of meiosis - pairing of homologous chromosomes/synapsis - chromatids break - non-sister chromatids exchange alleles - X-shaped structure formed - chiasma formed at position where crossing over occured - chiasmata become visible when homologous chromosomes unpair - chiasma holds homologous chromosomes together

How immobilized enzymes are used in industry (some examples, as well)

-easy to separate from product -can reuse enzymes -can have higher enzyme concentrations -increases enzyme stability -ex. Lactase Lactase obtained from cultured kluyveromyces lactis, a yeast that grows in milk a) added to milk b) immobilized on a surface or in beads of porous material (alginate beads)

Outline the process of glycolysis (5)

-occurs in cytoplasm - hexose is phosphorylated using ATP - hexose phosphate is split into two triose phosphates - oxidation by removal of H -conversion of NAD to NADH -net gain of two ATP -pyruvate produced at the end of glycolysis

List the solvent properties of water

-water is a very good solvent, sometimes called the "universal solvent" -substances that are able to dissolve in water are polar or ionic

How many sets of chromosomes are in a haploid cell?

1

How meiosis leads to infinite genetic variety (12)

1 chromosome from mother, 1 from father Homologous chromosomes pair in P1 Crossing over in P1 Recombination of linked genes Many possible points for crossing over Crossing over occurs in random positions 2 chromatids of M1 chromosomes are thus not identical Random orientation of bivalents in M1 A1 chromosomes move to opposite poles Independent assortment of chromosomes 2^23 combinations (without crossing over) 4 genetically different gametes from each meiosis

What is the structure of Fats/Triglycerides?

1 glycerol condensed with 3 fatty acids nonpolar C-H bonds in fatty acid "tails"

Differences between unique and highly repetitive sequences in nuclear DNA. (10)

1 in genome v many times Long base sequence v short (Maybe) genes v no genes (Maybe) translated v never Small difference between individuals v high variety Exons v introns Smaller proportion of genome v higher Satellite DNA is repetitive Repetitive sequences used profiling Prokaryotes don't usually contain repetitive sequences

What are the four parts surrounding a central carbon in an amino acid?

1) amino group (NH2) 2) carboxyl group (-COOH) 3) H atom 4) variable groups (determine the amino acid's properties, ex. polar (hydrophilic), nonpolar (hydrophobic), acid, or base) The only part that varies is the R-group

1 millimetre (mm)

1000 um

1 micrometer (um) =

1000nm

What are the 3 lines of defence from pathogens?

1st line of defense = surface barriers (skin / mucus), 2nd line of defense = innate immunity (non-specific), 3rd line of defense = adaptive immunity (specific)

How many sets of chromosomes are in a diploid cell?

2

Compound

2 or more elements combined in a fixed ratio

Quaternary structure

2 or more polypeptide chains aggregated into 1 macromolecule (ex. collagen (connective tissue), hemoglobin)

Name the 3 side reactions occurring in Glycolysis.

2ATP - 2ADP + 2P, 2NAD+ - 2NADH and 4(ADP +P) - 4ATP

What 3 things does the link reaction produce?

2CO2, 2NADH and 2acetylcoA

What 4 things does the krebs cycle produce per cycle?

2CO2, 3NADH, FADH2 and ATP

Polymers

3 or more covalently bonded monomers (subunits)

How many ATP molecules are made in ETC?

32

Photosynthesis equation

6CO2 + 6H2O ------> C6H12O6 + 6O2

biotic index

A (1-10) scale that gives a measure of the quality of an ecosystem by the presence and abundance of species living in it; Involves levels of tolerance, diversity and abundance of organisms

Enhancers

A DNA sequence that recognizes certain transcription factors that can stimulate transcription of nearby genes.

replication fork

A Y-shaped region on a replicating DNA molecule where new strands are growing.

glomerulus

A ball of capillaries surrounded by Bowman's capsule in the nephron and serving as the site of filtration in the vertebrate kidney.

Ecosystem

A biological community of interacting organisms and their physical environment.

exoskeleton

A body covering, typically made of chitin, that provides support and protection

red-green color blindness

A category of common, sex-linked human disorders involving several genes on the X chromosome; characterized by a malfunction of light-sensitive cells in the eyes; affects mostly males but also homozygous females.

cell membrane

A cell structure that controls which substances can enter or leave the cell.

Eukaryote

A cell that contains a nucleus and membrane bound organelles

What is a diploid cell

A cell that has two sets of chromosomes.

Denature

A change in the shape of a protein (such as an enzyme) that can be caused by changes in temperature or pH (among other things).

Describe what happens in G1

A checkpoint stage before DNA replication during which the cell grows; duplicates organelles e.g. mitochondria and extra cytoplasm including enzymes; synthesises proteins;

Describe what happens in G2

A checkpoint stage before division during which the copied DNA is checked for fidelity (mutations) and final metabolic reactions occur;

Mutagens

A chemical or physical agent that interacts with DNA and causes a mutation.

Urea

A chemical that comes from the breakdown of proteins

Ecosystem:

A community and also its environment (all biotic and abiotic factors)

climax community

A community composed of species that represents the final stage of colonization of a habitat. stable and fully developed community, result of ecological succession

cardiac cycle

A complete heartbeat consisting of contraction and relaxation of both atria and both ventricles

diabetes

A condition in which the body is unable to produce enough insulin, the hormone required for the metabolism of sugar

cartilage

A connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together.

Dihybrid trait

A cross using two traits

Food web

A diagram showing feeding relationships of organisms within an ecosystem or community. It consists of multiple interlinked food chains

Maltase

A digestive enzyme that breaks maltose into glucose.

Malaria

A disease caused by mosquitoes implanting parasites in the blood.

Hypothyroidism

A disorder caused by a thyroid gland that is slower and less productive than normal

phospholipid bilayer

A double layer of phospholipids that makes up plasma and organelle membranes.

ureter

A duct leading from the kidney to the urinary bladder.

Density independent limiting factors

A factor limiting population growth that equally effects small and large populations

Density dependent limiting factors

A factor limiting population growth that increases as the population increases

Biogeographic factor

A factor that effects distribution of species and ecosystems in geographic space and time (e.g. island size, climate)

Thylakoid

A flattened membrane sac inside the chloroplast, used to convert light energy into chemical energy.

coal

A fossil fuel that forms underground from partially decomposed plant material

Methane

A gas produced by bacteria from hydrogen and carbon dioxide

cystic fibrosis

A genetic disorder that is present at birth and affects both the respiratory and digestive systems.

prostate gland

A gland in males that contributes to the seminal fluid.

action spectrum

A graph that profiles the relative effectiveness of different wavelengths of radiation in driving a particular process.

Climograph

A graphical representation of basic climatic parameters (e.g. monthly average temperature and precipitation) at a certain location

complement system

A group of about 30 blood proteins that may amplify the inflammatory response, enhance phagocytosis, or directly lyse extracellular pathogens.

Community:

A group of different populations living together and interacting in a given area

Biome

A group of ecosystems that share similar climates and typical organisms

Population

A group of individuals that belong to the same species and live in the same area

Community

A group of interdependent organisms inhabiting the same region and interacting with each other

species

A group of organisms that are closely related and can mate to produce fertile offspring

Species:

A group of organisms that can interbreed and produce fertile, viable offspring

Tissue

A group of similar cells that perform the same function.

Species

A group of similar organisms that can breed and produce fertile offspring.

Clade

A group of species that includes an ancestral species and all its descendants.

Sigmoidal growth curve

A growth curve having a sigmoid or "S" shape (sigmoid curve)

Tropisms

A growth response of a plant toward or away from a stimulus

Polio

A highly contagious infectious disease of the spinal cord caused by a filterable virus.

Smallpox

A highly contagious viral disease characterized by fever, weakness, and skin eruption with pustules that form scabs; responsible for killing Native Americans.

Melatonin

A hormone manufactured by the pineal gland that produces sleepiness.

Leptin

A hormone produced by adipose (fat) cells that acts as a satiety factor in regulating appetite.

Insulin

A hormone produced by the pancreas or taken as a medication by many diabetics

Oxytocin

A hormone released by the posterior pituitary that stimulates uterine contractions during childbirth and milk ejection during breastfeeding.

Huntington's disease

A human genetic disease caused by a dominant allele; characterized by uncontrollable body movements and degeneration of the nervous system; usually fatal 10 to 20 years after the onset of symptoms.

Simpsons reciprocal index

A index that can be used to measure the biodiversity of an ecosystem

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Cambium

A layer of cells in a plant that produces new phloem and xylem cells.

myelin sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

Submucosa

A layer of the human digestive system that contains nerves, blood vessels, and lymph nodes

Sepal

A leaflike structure that encloses the bud of a flower.

DNA ligase

A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3' end of a new DNA fragment to the 5' end of a growing chain.

solvent

A liquid substance capable of dissolving other substances

Epididymis

A long, coiled duct on the outside of the testis in which sperm mature.

ovum

A mature egg cell

Evenness

A measure of biodiversity based on how even the abundance of each species in a geographic region or ecosystem

Richness

A measure of biodiversity based on the number of different species present in a geographic region or ecosystem

Biomass

A measure of the total dry mass of organisms within a particular region

lateral meristems

A meristem that thickens the roots and shoots of woody plants. The vascular cambium and cork cambium are lateral meristems.

biological control

A method of controlling pests using other living organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms to control the population of the pest species. using a predator parasite or pathogen to kill pests

Phospholipids

A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail.

striated muscle

A muscle that appears banded; also called skeletal muscle.

skeletal muscle

A muscle that is attached to the bones of the skeleton and provides the force that moves the bones.

Vagina

A muscular, elastic passageway that extends from the uterus to the outside of the body

If a thrombus blocks blood flow what happens?

A myocardial infarction and coronary heart disease

Cytoskeleton

A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement

Acetylcholine

A neurotransmitter that enables learning and memory and also triggers muscle contraction

prosthetic group

A non-protein, but organic, molecule that is covalently bound to an enzyme as part of the active site.

G0 phase

A nondividing state occupied by cells that have left the cell cycle, sometimes reversibly.

In prokaryotes, the absence of what allows translation to occur immediately after transcription?

A nuclear membrane

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

The monomer of a nucleic acid is called a nucleotide Each nucleotide consists of three basic components:

A pentose sugar, a phosphate group and a nitrogenous base

Legumes

A plant of the pea family. Most species have symbiotic nitrogen-fixing bacteria in structures called root nodules

Invasive species

A plant or animal species that is not native to a particular eosystem or location and has a tendency to spread causing damage to the environment, human economy and/or human healt

Photoperiodism

A plant's response to seasonal changes in length of night and day

Vaccines

A preparation that prevents a person from contracting a specific disease

in vitro fertilization

A procedure in which gametes are fertilized in a dish in the laboratory, and the resulting zygote is implanted in the uterus for development

DNA profiling

A procedure that analyzes DNA fragments to determine whether they come from a specific individual.

denitrification

A process facilitated by bacteria, in which nitrates (NO3) break down to molecular nitrogen (N2) only occurs in anaerobic conditions.

Chemiosmosis

A process for synthesizing ATP using the energy of an electrochemical gradient and the ATP synthase enzyme.

natural selection

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.

Fluorescence

A process in which phosphorescent material converts radiation into visible light

gradualism

A proposed explanation in evolutionary biology stating that new species arise from the result of slight modifications (mutations and resulting phenotypic changes) over many generations.

Nature reserve

A protected area of importance for wildlife, flora, fauna which is reserved and managed for conservation

Myosin

A protein present in muscle fibers that aids in contraction and makes up the majority of muscle fiber

Antigen

A protein that, when introduced in the blood, triggers the production of an antibody

What type of virus is HIV and what cells does it infect?

A retrovirus and helper T cells

cell wall

A rigid layer of nonliving material that surrounds the cells of plants and some other organisms.

collecting duct

A segment of the nephron that returns water form the filtrate to the bloodstream.

electron transport chain

A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.

metabolic pathway

A series of chemical reactions that either builds a complex molecule or breaks down a complex molecule into simpler compounds.

food chain

A series of steps in which organisms transfer energy by eating and being eaten

Emphysema

A serious disease that destroys lung tissue and causes breathing difficulties.

Dehydration

A serious reduction in the body's water content

estrogen

A sex hormone, secreted in greater amounts by females than by males. In nonhuman female mammals, estrogen levels peak during ovulation, promoting sexual receptivity.

Primer

A short segment of DNA that acts as the starting point for a new strand

nerve impulse

A signal transmitted along a nerve fiber.

sinoatrial node

A small mass of tissue that is made up of Purkinje fibers, ganglion cells, and nerve fibers, that is embedded in the musculature of the right atrium, and that originates the impulses stimulating the heartbeat -- called also S-A node, sinus node.

Ribosome

A small organelle in cells where proteins are made from amino acids

Plasmid

A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome

isotonic solution

A solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution

hypertonic solution

A solution in which the concentration of solutes is greater than that of the cell that resides in the solution

hypotonic solution

A solution in which the concentration of solutes is less than that of the cell that resides in the solution

atrioventricular node

A specialized mass of conducting cells located at the atrioventricular junction in the heart.

alien species

A species living outside its native distributional range or ecosystem introduced by humans.

indicator species

A species presence whose absence can be used as a indicator of environmental conditions

Endangered species

A species which has been categorized by the International Union for Conservation of Nature (IUCN) as likely to become extinct

allosteric site

A specific receptor site on some part of an enzyme molecule remote from the active site.

Starch

A storage polysaccharide in plants consisting entirely of glucose.

placenta

A structure that allows an embryo to be nourished with the mother's blood supply

ovule

A structure that develops within the ovary of a seed plant and contains the female gametophyte.

Cellulose

A substance (made of sugars) that is common in the cell walls of many organisms

non-competitive inhibitor

A substance that reduces the activity of an enzyme by binding to an allosteric site, changing its conformation so that it no longer binds to the substrate.

competitive inhibitor

A substance that reduces the activity of an enzyme by entering the active site in place of the substrate whose structure it mimics.

Golgi apparatus

A system of membranes that modifies and packages proteins for export by the cell

Chromatography

A technique that is used to separate the components of a mixture based on the tendency of each component to travel or be drawn across the surface of another material.

Homeostasis

A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level

Endosymbiosis

A theorized process in which early eukaryotic cells were formed from simpler prokaryotes.

Adaptation

A trait that helps an organism survive and reproduce

Aquaporins

A transport protein in the plasma membrane of a plant or animal cell that specifically facilitates the diffusion of water across the membrane

FSH

A tropic hormone produced by the anterior pituitary gland that targets the gonads. In females, FSH stimulates the ovaries to develop follicles (oogenesis) and secrete estrogen; in males, FSH stimulates spermatogenesis.

penis

A tube-shaped organ that extends from the trunk of the body just above the testes

Phagocytosis

A type of endocytosis in which a cell engulfs large particles or whole cells

Pinocytosis

A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes.

Cholesterol

A type of fat made by the body from saturated fat; a minor part of fat in foods.

determinate growth

A type of growth characteristic of most animals and some plant organs, in which growth stops after a certain size is reached.

indeterminate growth

A type of growth characteristic of plants, in which the organism continues to grow as long as it lives.

phytochrome

A type of light receptor in plants that mostly absorbs red light and regulates many plant responses, such as seed germination and shade avoidance.

Exopeptidases

A type of protease which hydrolyses the peptide bonds on the terminal amino acids of the peptide molecules formed by endopeptidases. They progressively release dipeptides and single amino acids.

Enzyme

A type of protein that speeds up a chemical reaction in a living thing

Lymphocytes

A type of white blood cell that make antibodies to fight off infections

Prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles

acrosome

A vesicle at the tip of a sperm cell that helps the sperm penetrate the egg

HIV

A virus that attacks and destroys the human immune system.

Casparian strip

A water-impermeable ring of wax in the endodermal cells of plants that blocks the passive flow of water and solutes into the stele by way of cell walls.

cell theory

A widely accepted explanation of the relationship between cells and living things

roots

Absorbs water and minerals from the ground. Anchors plant in ground.

4 main stages of krebs cycle

Acetyl CoA is combined with a 4C compound (forms 6C), 6C compound broken down into original 4C (CO2 produced), this involves oxidation reactions (NADH / FADH2 formed), there is also a small yield of ATP (one per cycle)

What is the name of the neurotransmitter that motor neurons release?

Acetylcholine

Muscle contraction (12)

Actin and myosin are proteins involved Release of calcium ions From sarcoplasmic reticulum Calcium reveals binding sites on actin Myosin heads from cross-bridges with binding sites on actin ATP binds to myosin heads Breaking cross-bridge to actin ATP hydrolysed to ADP + phosphate Causing myosin heads to change angle Myosin heads bind to new sites on actin further from centre of sarcomere ADP released Actin filaments slide inwards to centre of sarcomere

domesticated animals

Adapting animals for human use: Milk, meat, wool, and labor

third line of defense

Adaptive (acquired) immunity

In RNA what does Uracil pair with?

Adenine

Purines

Adenine and Guanine

Telophase

After the chromosome seperates, the cell seals off, Final Phase of Mitosis.

pancreatic juice

Alkaline mixture of water, enzymes, zymogens, sodium bicarbonate and other electrolytes

Metabolism

All of the chemical reactions that occur within an organism

Proteome

All proteins produced by a cell, tissue, or organism at any given time Every individual has a unique proteome (exception: identical twins, but become different as they age)

segregation of alleles

Alleles separate and move into different haploid gamete sex cells

What is the name of the site that a non-competitive inhibitor binds to?

Allosteric

Thyroxine

Also called thryoid hormone, thyroxine is produced and secreted by follicle cells in the thyroid gland. it targets all cells in the body and increases overall body metabolism.

Activation Energy

Amount of energy necessary to start a reaction (energy required to break bonds in reactions)

primary production

Amount of light energy converted to chemical energy by autotrophs.

2 glucose monomers

Amylose (linear) and amylopectin (branched)

Monocot

An angiosperm that has only one seed leaf.

Dicot

An angiosperm that has two seed leaves

Wildlife corridor

An area of habitat connecting wildlife populations separated by human activities or structures

Adhesion

An attraction between molecules of different substances

Commensalism

An ecological relationship between species in which one is benefited but the other is little affected

radicle

An embryonic root of a plant.

DNA polymerase

An enzyme that catalyzes the formation of the DNA molecule.

RNA primase

An enzyme that creates an RNA primer for initiation of DNA replication.

DNA helicase

An enzyme that unwinds the DNA double helix during DNA replication

adaptive radiation

An evolutionary pattern in which many species evolve from a single ancestral species

Glycogen

An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.

Opsonization

An immune response in which the binding of antibodies to the surface of a microbe facilitates phagocytosis of the the microbe by a macrophage

allergic reaction

An immunologic hypersensitivity reaction resulting from the unusual sensitivity of a patient to a particular medication; a type of adverse drug event.

Magnification

An increase in the apparent size of an object

global warming

An increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)

Zoonosis

An infectious disease that is transmissible from animals to humans.

What is enzyme inhibition?

An inhibitor stops the substrate from reaching the active site

competition

An interaction between individuals of the same species or different species whereby resources used by one are made unavailable to others. So a species using a resource reduces the amount available to other species using it

Human Genome Project

An international collaborative effort to map and sequence the DNA of the entire human genome.

Hemoglobin

An iron-containing protein in red blood cells that reversibly binds oxygen.

Mitochondria

An organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur.

Osmoconformers

An organism that allows its internal salt concentration to change with the salinity of the surrounding water

clone

An organism that is genetically identical to the organism from which it was produced

Consumers

An organism that obtains energy and nutrients by feeding on other organisms or their remains.

Phenotype

An organism's physical appearance, or visible traits.

pollinators

Animals that carry pollen from one flower to another

Mammals

Animals that have hair and produce milk for their young

Which DNA strand is transcribed into RNA?

Antisense

Autosomes

Any chromosome that is not a sex chromosome

Variation

Any difference between individuals of the same species.

Centromere

Area where the chromatids of a chromosome are attached

Isotopes

Atoms of the same element that have different numbers of neutrons

Vaccination (12)

Attenuated form of pathogen Introduced to body by injection Antigens in vaccine cause antibody production Pathogen engulfed by macrophage Each type of lymphocyte recognises specific antigen Macrophage activate helper T-cells Which activate B-cells B-cells divide to form memory cells B-cells divide to form plasma cells Result is specific immunity Vaccination causes slow production of antibodies and lower level Contact with disease leads to rapid production and higher level

Hydrogen bond

Attraction (weak) between a partially positive H atom of one polar molecule and a partially negative atom (O or N) of another polar molecule Bond between bases pairs in DNA

Cohesion

Attraction between molecules of the same substance

What is apical dominance?

Auxins promote growth in apex but inhibit growth in buds

What happens during action potential?

Axon is depolarised to 35mV Potential difference is reversed temporarily to be net negative outside Influx of Na+ into axon cytoplasm by facilitated diffusion through voltage gated channel (electrochemical gradient) Na+ channels open Self - propagation - localised current creates chain effect

What 3 things happen in resting potential during a nerve impulse?

Axon is polarised at -70mV Net positive charge outside membrane Pumping of sodium and potassium ions in opposite directions via the sodium potassium pump (3Na+ out, 2K+ in)

What is repolarisation and what happens (4)?

Axon returns to resting potential Positive K+ move out of membrane Na+ channels close K+ channels open

What are antibodies produced by?

B lymphocytes

Body Mass Index (BMI)

BMI=(weight in kg)/(height in m^2) metric

nitrifying bacteria

Bacteria that change dissolved ammonia into nitrite compounds or nitrites into nitrate compounds.

Nitrifying bacteria

Bacteria that facilitate part of the process known as nitrification, as part of the nitrogen cycle, e.g. Nitrosomonas convert ammonia to nitrite and Nitrobacter convert nitrite to nitrate

Denitrifying bacteria

Bacteria that facilitate the process known as denitrification, as part of the nitrogen cycle, e.g. Pseudomonas

Sacromere

Basic contracting unit of muscle cell consits of actin and myosin filaments between z-lines in a muscle cell

Mixtrophic

Being both auto- and heterotrophic

distal convoluted tubule

Between the loop of Henle and the collecting duct; Selective reabsorption and secretion occur here, most notably to regulate reabsorption of water and sodium

What type of movement is segmentation and what muscles contract to allow it to happen?

Bidirectional mixing of food in small intestine and non-sequential circular muscles

4 types of animal cloning:

Binary fission, fragmentation, budding and parthenogenesis

What does RNA polymerase do in transcription?

Binds to a promoter and unwinds DNA breaking the H bonds between complementary bases

Leukemia

Blood condition of white cells; malignant (cancerous) condition.

systolic pressure

Blood pressure in the arteries during contraction of the ventricles.

Veins

Blood vessels that carry blood back to the heart

analogous structures

Body parts that share a common function, but not structure

genetic modification

Branch of biotechnology that alters the genes in biological organisms to achieve a medicinal or agricultural purpose

Epidemiology

Branch of medical science concerned with the incidence, distribution, and control of diseases that affect large numbers of people.

Dendrites

Branchlike parts of a neuron that are specialized to receive information.

Digestion

Breakdown of food substances into simpler forms that can be absorbed and used

Cross breeding

Breeding animals from different varieties to produce a breed with traits of both parents

How are amino acids attached in translation?

By tRNA-activating enzymes

cell respiration equation

C6H12O6 + 6O2 ----> 6CO2 + H2O + energy

Monosaccharides

CH2O=empirical formula Examples: glucose- blood sugar fructose- fruit sugar galactose ribose- structural component in RNA Importance: -produced by photosynthesis -used in cellular respiration (to make energy) -summary: energy storage and release -also used to build structures

Name the most frequent elements in life

CHON (Carbon, hydrogen, oxygen, nitrogen, and are main elements found in organic molecules in organisms)

What is the general formula for saturated fats?

COOH-(CH2)n-CH3

How does cancer form?

Cancer is usually caused by genetic abnormalities due to a variety of different sources called carcinogens or due to inheritance or errors in DNA replication

Organic

Carbon compounds found in living organisms, almost all carbon compounds are organic

What is a Carcinogens

Carcinogens are agents that can cause cancer, such as viruses, X-Rays, UV Radiation and many chemical agents

Sperm duct

Carries sperm from testes to urethra

axons

Carry impulses away from the cell body

Enzymes

Catalytic proteins that change the rate of reactions w/o being consumed; they lower activation energy

Sickle-cell anemia (12)

Caused by gene mutation Due to base substitution Changes code on DNA Lead to change in transcription on mRNA DNA changes from CTC to GAG to GTG Leads to change in translation tRNA adds wrong amino acid to polypeptide chain Glutamic acid is replaced by valine Produces abnormal hemoglobin Causes sickle shape of red blood cells Lower O2 carrying capacity Sickle-cell allele is codominant

Meiosis

Cell division that produces reproductive cells in sexually reproducing organisms

Cytokinesis in animal cells

Cell membrane is drawn inward until the cytoplasm is pinched into two nearly equal parts

Vacuoles

Cell organelle that stores materials such as water, salts, proteins, and carbohydrates

basement membrane

Cells at the base of an epithelial layer are attached to this.

type 2 pneumocytes

Cells in the alveolus wall that secrete fluid to keep the inner surface of the alveolus moist and allow gases to dissolve. The fluid also contains a surfactant that prevents the sides of the alveoli from sticking together by reducing surface tension

B cells

Cells manufactured in the bone marrow that create antibodies for isolating and destroying invading bacteria and viruses.

Explain why cells need to supercoil their DNA molecules.

Cells need to super coil because it results in condensed structures called sister chromatids. -Become more organized

3 main stages of Metaphase:

Centrosome spindle fibres attach to the centromere of each chromosome Spindle fibres contract and move the chromosomes towards the cell centre Chromosomes form a line along the equator (middle) of the cell

How do enzymes control metabolic pathways?

Chains and cycle of enzyme, catalyzed reactions; ex. Cellular respiration - glycolysis: a chain, krebs cycle

Evolution

Change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.

Polygenic traits are...

Characteristics controlled by more than two gene loci, bell-shaped distribution pattern and can be influenced by environment

Monogenic traits are...

Characteristics that are controlled by a single gene locus and have a finite pattern of expression

histamine

Chemical stored in mast cells that triggers dilation and increased permeability of capillaries.

3 types of Mechanical Digestion

Chewing, churning and segmentation

What is the point of exchange between non-sister chromatids called?

Chiasmata

Prophase

Chromosomes become visable, nuclear envelop dissolves, spindle forms

3 main stages of Telophase:

Chromosomes decondense (DNA forms chromatin) Nuclear membranes form around the two identical chromosome sets Cytokinesis occurs concurrently

Metaphase

Chromosomes line up in the middle of the cell

7 Prokaryotic and Eukaryotic DNA differences.

Circular v linear 1 chromosome v many Naked DNA v histones Plasmids v no plasmids No introns v introns and exons In nucleoid v in nucleus 1 replication point v many

Blood clotting (5)

Clotting factors released by platelets Series of reactions Prothrombin to thrombin Soluble fibrinogen to insoluble fibrin Mesh of fibrin

Exons

Coding segments of eukaryotic DNA.

List the cohesive properties of water

Cohesion, surface tension

Secondary structure

Coils and foils (due to hydrogen bonds at regular intervals), Alpha helix causes coiling (ex. keratin), pleated sheet is parallel (ex. silk)

specific immune response

Collection of several immunological events in which lymphocytes recognize the presence of a particular antigen and act to eliminate it.

Habitiat

Combined biotic and abiotic factors found in an area where an organism lives

gene pools

Combined genetic information of all the members of a particular population

By what type of cells are organic molecules loaded and unloaded in phloem transport?

Companion cells

apical dominance

Concentration of growth at the tip of a plant shoot, where a terminal bud partially inhibits axillary bud growth.

Ligament

Connects bone to bone

tendon

Connects muscle to bone

endocrine system

Consists of glands that control many of the body's activities by producing hormones.

Photosynthesis

Conversion of light energy from the sun into chemical energy.

What is Chemiosmosis?

Coupling of ATP synthesis with diffusion of H+ down a concentration gradient

Ethical issues of therapeutic cloning (11)

Creation of an embryo to supply embryonic cells to medicine Transfer of nucleus from somatic cell into en-nucleated egg Stimulated by electric shock to begin mitosis Stem cells from embryos have greater flexibility Pluripotent cells can give rise to all cells in the body No rejection of transplant as all DNA would match Elimination of pain for organ recipient Eliminate organ and tissue shortages Destruction of human embryos not ethically acceptable Process of extracting stem cells kills embryo Many attempts before success is attained

What are the 4 types of Cyclins and what is their use?

Cyclin D - causes G0 to move to G1 and G1 to move to S phase Cyclin E - causes the cell to prepare for replication in S phase Cyclin A - activates DNA replication in S phase Cyclin B - causes the mitotic spindle to begin to form and other tasks needed in the preparation of mitosis

What are Cyclins?

Cyclins are a family of regulatory proteins that control the progression of the cell cycle. Cyclins activate cyclin dependent kinases (CDKs), which control cell cycle processes through phosphorylation

Example of Autosomal Recessive disease:

Cystic fibrosis

3 main stages of Cytokinesis:

Cytoplasmic division occurs to divide the cell into two daughter cells Each daughter cell contains one copy of each identical sister chromatid Daughter cells are genetically identical

Pyrimidines

Cytosine and Thymine

nucleosome

DNA and nucleosome around which it coils

mutations

DNA changes caused by environmental factor

What does DNA polymerase III do?

DNA polymerase III covalently joins free nucleotides together

What does DNA primase do?

DNA primase generates a short RNA primer on each strand

6 events in Interphase:

DNA replication (during S phase) Organelle duplication Cell growth Transcription / translation Obtaining nutrients Respiration (cellular)

S phase

DNA replication occurs

The Meselson-Stahl experiment supported the theory that...

DNA replication occurs via a semi-conservative process

DNA profiling (13)

DNA sample obtained From hair/blood DNA amplified Highly repetitive sequence used DNA cut into fragments Using restriction enzymes Gel electrophoresis used to separate DNA fragments Fragments separated by size Pattern of bands is unique to individual Forensic use DNA from crime scene Paternity testing Genetic screening

Genes

DNA segments that serve as the key functional units in hereditary transmission.

3 main stages of Prophase:

DNA supercoils and condenses (forms visible chromosomes) Nuclear membrane dissolves Centrosomes move to poles and begin to produce spindle fibres

Melanistic

Dark varieties of typically light coloured insects

Putrefaction

Decomposition of organic matter by microorganisms

Mortality

Decreases to population size as a result of death (e.g. predation, senescence)

Emigration

Decreases to population size by movement of individuals to external populations

What does increasing methylation do to DNA?

Decreases transcription

What are the 3 repeating steps of PCR?

Denaturation (DNA heated to separate strands), Annealing (primers attach to ends of target sequence) and elongation (heat-tolerant polymerase copies strands)

Myogenic

Describes muscle tissue (heart muscle) that generates its own contractions.

Dihybrid crosses

Determine allele combinations of offspring for two genes that are unlinked (FOIL then cross)

3 Heterotrophs

Detritivores, saprotrophs and consumers

type 2 diabetes

Diabetes of a form that develops especially in adults and most often obese individuals and that is characterized by high blood glucose resulting from impaired insulin utilization coupled with the body's inability to compensate with increased insulin production.

Type 1 diabetes

Diabetes of a form that usually develops during childhood or adolescence and is characterized by a severe deficiency of insulin, leading to high blood glucose levels.

Cladogram

Diagram that shows the evolutionary relationships among a group of organisms

Gersmehl diagrams

Diagrams showing the inter-relationships between nutrient stores and flows in an ecosystem

Alleles

Different forms of a gene

osmosis

Diffusion of water through a selectively permeable membrane

Mitosis v meiosis DISCO PUG

Divisions, independent assortment, synapsis, crossing over, outcome, ploidy, use, genetics

Archea

Domain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan

Antibiotics

Drugs that block the growth and reproduction of bacteria

DNA replication (13)

During S phase of interphase Semi-conservative Separation of strands by Helicase Hydrogen bonds between 2 strands broken Each strand of parent DNA used as template Deoxynucleoside triphosphate provides energy Synthesis continues on leading strand not lagging strand Formation of Okazaki fragments on lagging strand Synthesis occurs in 5' to 3' direction RNA primer synthesised on parents DNA using RNA primase DNA polymerase III adds nucleotides Complementary base pairing Adenine with Thymine and Guanine with Cytosine

What is the difference between a chromosomes and sister Chromatid?

During the cell division, more precisely during the S-phase of interphase, DNA is replicated. The resulting two identical copies of DNA are connected to each other at the centromere. Each copy is called a chromatid. A chromosome, before cell division is formed by one chromatid while it is formed pf two chromatids after cell division.

Germination

Early growth stage of a plant embryo

competitive exclusion principle

Ecological rule that states that no two species can occupy the same exact niche in the same habitat at the same time

Nonpolar covalent bonds

Electrons shared equally

membrane proteins

Embedded proteins that perform specific functions for the cell membrane.

Mesocosms:

Enclosed environments with controlled conditions (e.g. terrariums), they can be used to study sustainability

zooxanthellae

Endosymbiotic algae that inhabit the endoderm of tropical cnidarians such as corals, sea anemones, and jellyfish. They are mutualistic!! Coral provides algae with a protected environment with sufficient light while the algae provides coral with products of photosynthesis

light energy

Energy in the form of moving waves of light

How are pyramids of energy measured?

Energy units per area per time

Lipids

Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.

Induced fit model

Enzyme and substrate fit together, but enzyme conforms to substrate

Substrate

Enzyme reactant

RNA polymerase

Enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription

Non-disjunction

Error in meiosis in which homologous chromosomes fail to separate.

Transpiration

Evaporation of water from the leaves of a plant

Scrotum

External sac that contains the testes

Bottom-up limiting factors

Factors that limit population growth by affecting resources or lower tropic levels (e.g. interspecific competition for resources)

oviduct

Fallopian tube; tube that carries eggs from an ovary to the uterus

Unsaturated

Fat with less than the maximum number of hydrogens in one or more of its fatty acid chains

Energy stores

Fats are the body's chief form of stored energy

Saturated

Fats with the maximum number of hydrogens.

Lipids

Fats, phospholipids, steroids, waxes All lipids are hydrophobic

Uterus

Female organ of reproduction used to house the developing fetus.

Pistil

Female part of the flower

What is the pistil in a plant?

Female parts including stigma, style and ovule

kidney

Filters waste from the blood like urea, water, salt and proteins.

Villi

Fingerlike extensions of the intestinal mucosa that increase the surface area for absorption

Speciation

Formation of new species

Spermatogenesis

Formation of sperm

Macrophages

Found within the lymph nodes, they are phagocytes that destroy bacteria, cancer cells, and other foreign matter in the lymphatic stream.

What is the function, structure, and importance of structure and function together of glycogen?

Function: energy storage in animals (esp. in liver and muscles) Structure: more highly branched alpha glucose F&S: quick release needed, must be branched

What is the function, structure, and importance of structure and function together of starch?

Function: energy storage in plants Structure: chain of alpha glucose with same bond orientation Amylose=unbranched Amylopectin=branched (though less than glycogen) F&S: flat, too big to dissolve

What is the function, structure, and importance of structure and function together of cellulose?

Function: structural material (plant cell walls) Structure: chain of beta glucose with alternating bond orientations, gives strength (to build strong cell walls) F&S: stacked, linear model, stronger, not soluble, good for structure, not digestable

What does an ecological niche describe?

Functional position and role of an organism within its environment

B blood

Galactose

synpase

Gap between neurons

What does Ethylene do?

Gas that stimulates maturation/aging and ripening and leaf loss

greenhouse gases

Gases such as carbon dioxide, methane, nitrous oxide, water vapor, and ozone in the atmosphere which are involved in the greenhouse effect.

memory cells

General term for lymphocytes that are responsible for immunological memory and protective immunity.

How can genes be unlinked?

Genes occur independently provided the genes are on separate chromosomes, unlinked genes segregate independently during meiosis (random assortment of homologous chromosomes)

Name the 4 main steps of Glycolysis.

Glucose (6C), Fructose, 1-6 bisphosphate (6C), 2 x G3P (3C) and 2x pyruvate (3C)

What are the 4 basic stages of glycolysis?

Glucose is phosphorylated by ATP, 6C sugar splits (lysis) into two triose phosphates (3C), 3C sugars are oxidised to form reduced carriers (NADH), ATP is produced (net gain = 2 ATP)

Anaerobic respiration (8)

Glucose to pyruvate Oxidation reactions using NAD to produce reduced NADH Less ATP produced than aerobic NAD regenerate by reducing pyruvate Pyruvate to ethanol + CO2 in yeast fermentation Pyruvate to lactic acid in humans Cytoplasm Only use sugars

Linked genes

Group of genes whose loci are on the same chromosome, function as a single inheritable unit and not follow law of independent assortment

Population

Group of organisms of same species in same area

Population:

Group of organisms of the same species, living in the same area at the same time

Species

Group of organisms that interbreed/produce fertile offspring

Phototropism

Growth of a plant shoot toward or away from light.

Adhesion

H bonds holding molecules to another substance

Cohesion

H bonds holding water molecules together

What do roots pump into the soil to displace minerals?

H+ ions

secondary spermatocytes

Haploid cells resulting from the first meiotic division of spermatogenesis. Secondary spermatocytes are ready to enter meiosis II.

compact bone

Hard, dense bone tissue that is beneath the outer membrane of a bone

Bryophyta

Has no vascularisation (i.e. lacks xylem and phloem) Has no 'true' leaves, roots or stems (are anchored by a root-like structure called a rhizoid) Reproduce by releasing spores from sporangia (reproductive stalks) Examples include mosses and liverworts

Angiospermophyta

Has vascularisation Have leaves, roots and stems (individual species may be highly variable in structure) Reproduce by seeds produced in ovules within flowers (seeds may develop in fruits) Examples include all flowering plants and grasses

Coniferophyta

Has vascularisation Have leaves, roots and stems (stems are woody and leaves are waxy and needle-like) Reproduce by non-motile gametes (seeds) which are found in cones Examples include pine trees and conifers

Filicinophyta

Has vascularisation (i.e xylem and phloem) Have leaves, roots and stems (leaves are pinnate - consisting of large fronds divided into leaflets) Reproduce by releasing spores from clusters called sori on the underside of the leaves Examples include ferns

Platyhelmintha

Have bilateral symmetry Have a mouth but no anus (single entrance body cavity) Have a flattened body shape to increase SA:Vol ratio and may be parasitic Examples include tapeworms and planaria

Annelida

Have bilateral symmetry Have a separate mouth and anus Body composed of ringed segments with specialisation of segments Examples include earthworms and leeches

Chordata

Have bilateral symmetry Have a separate mouth and anus Have a notochord and a hollow, dorsal nerve tube for at least some period of their life cycle Examples include mammals, birds, reptiles, amphibians and fish (also invertebrate sea squirts)

Anthropoda

Have bilateral symmetry Have a separate mouth and anus Have jointed body sections / appendages and have a hard exoskeleton (chitin) Examples include insects, crustaceans, spiders, scorpions and centipedes

Mollusca

Have bilaterial symmetry Have a separate mouth and anus Body composed of a visceral mass, a muscular foot and a mantle (may produce shell) Examples include snails, slugs, octopi, squid and bivalves (e.g. clams)

Cnidaria

Have radial symmetry Have a mouth but no anus (single entrance body cavity) May have tentacles with stinging cells for capturing and disabling prey Examples include jellyfish, sea anemones and coral

What does helicase do?

Helicase separates the DNA strands to form a replication fork (breaks the hydrogen bonds between complementary base pairs)

Hypertonic:

High solute concentration (gains water)

List the thermal properties of water

High specific heat, high heat of vaporization, and high boiling point

pilli

Hollow tubes used to move cells or exchange DNA between bacteria by conjunction.

What are separated during Meiosis I?

Homologous pairs

Example of Autosomal Dominant disease:

Huntington's - nerodegeneration

In aquatic ecosystems, CO2 either remains dissolved or forms...

Hydrogen carbonate ions

What does hyperpolarised mean?

If too many K+ move out.

promoter-proximal elements

In eukaryotes, regulatory sequences in DNA that are close to a promoter and that can bind regulatory transcription factors.

hemolymph

In invertebrates with an open circulatory system, the body fluid that bathes tissues.

Codominance in blood (7)

In multiple alleles there are more than 2 alleles Affect phenotype IA, IB + i control blood groups IA + IB are codominant, i is recessive When A + B are present they give AB A + B can be heterozygous ii organisms = group 0

What does prostaglandin do and where is it produced?

Increases body temperature and in the hypathalamus

What does insulin do?

Increases glucose uptake by cells

Immigration

Increases to population size by movement of individuals from external populations

Natality

Increases to population size through reproduction (i.e. births)

independent assortment

Independent segregation of genes during the formation of gametes

pure breeding

Individuals that are homozygous that will always produce the same offspring when crossed together

Nitrous Oxide

Inhaled anesthetic, less likely to lower blood pressure than other agents, and has the smallest effect on respiration

Noncompetitive inhibition

Inhibitor binds to another part of the enzyme (allosteric site) altering its conformation (shape); ex. heavy metal poisoning (heavy metals bind to allosteric sites on enzymes)

Competitive inhibition

Inhibitor competes for active site, mimics substrate (ex. Penicillin and enzyme for cell wall synthesis in bacteria)

What happens in competitive inhibition?

Inhibitor directly blocks the active site of the enzyme

What does abscisic acid do?

Inhibits plant growth and development and seed dormancy

Translation (13)

Initiation, elongation and termination mRNA binds to small sub-unit of ribosome Ribosome slides along mRNA to start codon Anticodon on tRNA pairs with codon on mRNA Complementary base pairing AUG is start codon 2nd tRNA pairs with next codon Peptide bonds form between amino acids Ribosome moves along mRNA by one codon Movement in 5' to 3' direction tRNA that lost its amino acid detaches Another tRNA moves into A site Stop codon is eventually reached

ulna bone

Inner and larger bone of the forearm, attached to the wrist and located on the side of the little finger.

Cofactors

Inorganic, nonprotein helpers (ex. zinc, iron, copper)

Position and function of proteins in membranes (14)

Integral proteins embedded in phospholipid bilayer Peripheral proteins on surface Some integral proteins extend from one side to the other Hormone binding sites (Insulin) Enzymes (Sucrase) Cell adhesion Cell to cell communication recognition Contact inhibition Channels for passive transports Pumps for active transport Receptors for neurotransmitters Such as acetylcholine Electron carriers e.g. ETC Pigments

What happens during Interphase

Interphase is an active period in the life of a cell during which many metabolic reactions occur such as protein synthesis, DNA replication and an increase in the number of mitochondria and/or chloroplast(plant cells)

Intraspecific interactions

Interplay between members of the same species that affects one or more of them

Interspecific interactions

Interplay between species that affects one or more of them

Peristalsis

Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.

What is the role of type I pneumocytes and how are they adapted?

Involved in gas exchange between alveoli and capillaries and are extremely thin to minimises gas diffusion distances

What 2 things can the many properties of water be attributed to?

Its polarity and hydrogen bonds

Condensation reaction/dehydration synthesis

Joins monomers: one monomer provides a hydroxyl group while the other provides a hydrogen to form a water molecule, which is removed.

hinge joint

Joint between bones (as at the elbow or knee) that permits motion in only one plane

3 examples of cationic minerals

K+, Na+ and Ca2+

Use of karyotyping (10)

Karyotype is number and type of chromosomes in a cell Cells collected from chorionic villus Requires cells in metaphase Chromosomes arranged in pairs according to size Identify gender Male is XY, female is XX Identify chromosome mutations Down syndrome due to extra chromosome 21 Pre-natal diagnosis of chromosome abnormalities May lead to decision to abort fetus

Use of lactase (9)

Lactose is a disaccharide found in milk Lactase digests lactose into glucose + galactose Lactase produced naturally by yeast Lactase added to milk to reduce level of lactose Lactose-intolerant people cannot drink milk Glucose and galactose are sweeter than lactose Less sugar is needed in food production from milk Bacteria ferment glucose and galactose faster than lactose so production of yoghurt is faster Glucose and galactose are more soluble so improve ice cream texture

tricep

Large muscle that covers the entire back of the upper arm and extends the forearm.

cell body

Largest part of a typical neuron; contains the nucleus and much of the cytoplasm

spongy bone

Layer of bone tissue having many small spaces and found just inside the layer of compact bone.

In DNA replication, synthesis is continuous on which strand?

Leading strand

Bones are connected to other bones by...

Ligaments

What are the cell walls of the xylem reinforced with and what 2 types?

Lignin and spiral or annular

What type of molecule is cellulose (component of plant cell wall) and what arrangement are its subunits bound?

Linear polysaccharide and 1-4

Symbiosis

Literally "living together," a close association between two or more species

Taiga characteristics

Litter + slow transfer of energy

threshold potentials

Local potentials that are just large enough to open the voltage-dependent Na+ channels

locus

Location of a gene on a chromosome

Explain the graph of the effects of inhibition on enzyme kinetics

Look at the top graph

Hypotonic:

Low solute concentration (loses water)

Ventricules

Lower chambers of the heart

LH

Luteinizing hormone, ovulation and egg release, maturation of egg, release of testosterone in males.

6 key features of villi:

MRSLIM: Microvilli (⇧ SA:Vol) Rich blood network Single layer epithelium Lacteals (absorb lipids) Intestinal crypts (exocrine) Membrane proteins

Unicellular

Made of a single cell

Multicellular

Made up of more than one cell.

non-cyclic phosphorylation

Makes ATP, NADPH, and O2. Oxygen is released and carries high-energy electrons from the light reaction to the Calvin Cycle.

What does Acetylation do to DNA?

Makes it less tightly packed

What does Methylation do to DNA?

Makes it more tightly packed

Stamen

Male part of the flower

Coral

Marine invertebrates in the class Anthozoa (phylum Cnidaria). They typically live in compact colonies of identical individual polyps. The group includes the important reef builders that secrete calcium carbonate to form a hard skeleton

feed conversion ratio

Mass of feed/mass of desired output

Birds

May or may not fly, with vertebra, lay eggs, have feathers

Surface tension

Measurement of the difficulty to break or stretch the surface of a liquid

mucous membrane

Membrane that secretes mucus that lubricates the surface of organs and keeps them moist.

Law of Segregation

Mendel's law that states that the pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete

principle of dominance

Mendel's second conclusion, which states that some alleles are dominant and others are recessive

Catabolism

Metabolic pathways that break down molecules, releasing energy.

Anabolism

Metabolic pathways that construct molecules, requiring energy.

semi-conservative replication

Method of DNA replication in which parental strands separate, act as templates, and produce molecules of DNA with one parental DNA strand and one new DNA strand

Nitrogen-fixing bacteria

Microorganisms capable of fixing atmospheric nitrogen into compounds that plants and other organisms can assimilate. Bacteria can be free-living in the soil (e.g. Azotobacter) or living mutualistically with plants roots (e.g. Rhizobium)

Capillaries

Microscopic vessel through which exchanges take place between the blood and cells of the body

Explain how mitosis produces two genetically identical nuclei.

Mitosis is divided into four stages; prophase, metaphase, anaphase and telophase. During prophase, the chromosomes become visible under a light microscope as they super coil and therefore they get shorter and more bulky. The nuclear envelope disintegrates and the spindle microtubules grow and extend from each pole to the equator. At metaphase the chromatids move to the equator. The sister chromatids are two DNA molecules formed by DNA replication and are therefore identical. These sister chromatids are then separated in anaphase as the spindle microtubules attaches to centromere and pulls the sister chromatids to opposite poles. As the sister chromatids separate they are called chromosomes. This means that each pole has the same chromosomes (same genetic material). Finally the microtubules break down, the chromosomes uncoil and th

Blood glucose concentration

Monitored and controlled by the pancreas

Difference between Monocotyledon and Dicotyledon roots.

Monocotyledon has a larger stele and the vessels form a circle around the pith with the phloem on the outside

What are the different types of unsaturated fats?

Monounsaturated, polyunsaturated, cis, and trans

abduction

Movement away from the midline of the body

Ventilation

Movement of air into and out of lungs Inspiration: volume of thorax increases, pressure decreases, external intercostal muscles contract, ribcage moves up and out, diaphragm contracts so moves down, internal intercostal muscles relax Opposite for expiration

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

adduction

Movement toward the midline of the body

Polysaccharides

Multiple monosaccharides bonded covalently

Polysome

Multiple ribosomes translate a single mRNA sequence simultaneously

bicep

Muscle that produces the contour of the front and inner side of the upper arm; lifts the forearm and flexes the elbow.

What is a mutagen?

Mutagens are agents that can cause mutations in one's DNA which can lead to cancer. Mutagens and carcinogens are strongly correlated and many mutagens can be carcinogens Mutagens may be physical, chemical or biological in origin:

Heart beat control (7)

Myogenic muscle contration Contractions controlled by sinoatrial node Pacemaker in wall of right atrium Signal to contract transmitted across atria Impulses from medulla Fone nerve increases rate Adrenalin increases rate

A blood

N-acetylegalactosamine

AB blood type

N-acetylegalactosamine and galactose

Electron Transfer Chain (12)

NAD is reduce by gaining 2 H atoms and 2 electrons Reduce NAD is produced in glycolysis Reduced NAD delivers electrons to ETC In inner mitochondrial membrane Electrons release energy as they flow along chain Electrons from ETC accepted by oxygen Electron carriers act as proton pumps Proton gradient across inner mitochondrial membrane Energy from electrons used to pump protons into intermembrenal space ATP synthase in inner mitochondrial membrane Energy released as protons pass down the gradient ATP synthase converts ADP to ATP

seminiferous tubules

Narrow, coiled tubules that produce sperm in the testes.

Milankovich cycles

Natural cycles in the Earths position (changes in orbit, axis tilt and precession) that are used to explain climate changes over the last 400,000 yrs.

stabilizing selection

Natural selection that favors intermediate variants by acting against extreme phenotypes

Do Saturated Fatty Acids have double bonds and what form are they at room temperature?

No and solid (animal fat)

Porifera

No body symmetry (asymmetrical) No mouth or anus (have pores to facilitate the circulation of material) May have silica or calcium carbonate based spicules for structural support Examples include sea sponges

Down Syndrome causes (12)

Non-disjunction Pair of homologous chromosomes fair to separate during A1 One gamete receives 2 chromosomes A1/2 Fertilisation leads to 47 chromosomes Most common form = trisomy 21 Risk increases with mother's age Incorrect spindle attachment Non-separation of chromatids in A2 Centromeres not dividing During gamete formation Gamete receives 2 chromosomes of same type.

Inorganic

Not consisting of or deriving from living matter.

Proteins

Nutrients the body uses to build and maintain its cells and tissues

Secondary succession

Occurs when succession starts on existing soil following a natural or artificial disturbance

Ex situ conservation

Off-site conservation or the conservation of genetic resources outside natural ecosystems

In situ conservation

On-site conservation or the conservation of genetic resources in natural ecosystems

What is a Oncogene?

Oncogenes are mutated forms of proto-oncogenes (which typically control synthesis of proteins involved in cell signaling or cell division). These cells with activated oncogenes cause uncontrolled growth and cell division, prevent the cancer cell from dying and allow them to invade other tissues.

Polar covalent bonds

One atom more electronegative than the other (creates partial charges)

vena cava

One of two large vessels (superior and inferior) that return deoxygenated blood to the right atrium of the heart.

Krebs Cycle (10)

Only occurs in aerobic conditions In mitochondria AcetylcoA from link reaction release acetyl group NADH + H+ and CO2 are formed Decarboxylation Acetyl group joined to a 4-C molecule to form a 6-C molecule To 5-C molecule To 4-C molecule Converted into original 4-C molecule + cycle repeats 1 molecule of ATP made during this step

Law of tolerance - 3 zones

Optimal zone (preferred niche), zone of stress, zone of intolerance

Primary structure

Order of amino acids, each type of protein has a unique primary structure, sequence determines 3D conformation Amino acid substitution: hemoglobin, sickle-cell anemia

Coenzyme

Organic helpers (ex. vitamins)

Formation of peat

Organic matter that is not fully decomposed in anoxic or acidic soils will become peat

Producers

Organisms that make their own food

Tertiary structure

Overall 3D shape of the polypeptide Contortions from R-group bonding -hydrophobic interactions (nonpolar side chains) -disulfide bridges (strong covalent bonds) -hydrogen bonds (between polar side chains) -ionic bonds (charged side chains)

Chiasmata formation (8)

P1 meiosis Synapsis Chromatids break Non-sister chromatids swap x-shaped structure formed Chiasma form a position of crossing over Visible when homologous chromosomes unpair Hold homologous chromosomes together

synapsis

Pairing of homologous chromosomes

cyclic phosphorylation

Part of the light-dependent reactions in photosynthesis where electrons travel on a short-circuit pathway to replenish ATP levels only

carrier membrane protein

Passage of molecule through membrane, combine with substance to selectively move and adjust levels of blood glucose

punctuated equilibrium

Pattern of evolution in which long stable periods are interrupted by brief periods of more rapid change

Peat formation

Peat forms when organic matter is not fully decomposed because of anaerobic conditions in waterlogged soils.

Active phytochrome

Pfr

Anaphase

Phase of mitosis in which the chromosomes separate and move to opposite ends of the cell

2 Autotrophs (producers)

Photosynthesis and chemosynthesis

Example of a source in a plant

Photosynthetic tissue (leaves)

habitat

Place where an organism lives

Role of auxin (11)

Plant hormone Produced by tip of stem Causes transport of hydrogen ions from cytoplasm to cell wall Decrease in pH breaks bonds between cell wall fibres Makes cell walls flexible Auxin makes cells enlarge Gene expression altered to promote cell growth Positive phototropism is growth towards light Shoot tip senses direction of light Auxin moves to darker side Cell on dark side elongate

Auxins

Plant hormones that lead to phototropism by elongating the dark side of the plant

Absorption of minerals from soil into roots (11)

Plants absorb minerals in ionic form Nitrate/phosphate/potassium By facilitated diffusion Movement of ions from high concentration to low concentration Root hair cells provide a large surface area Fungal hyphae help to absorb minerals Can be absorbed by active transport Ion concentration smaller outside root Active transport requires energy Occurs through pump Proton pump transports hydrogen ions out of cell

Insectivorous plants

Plants that derive some or most of their nutrients (but not energy) from trapping and consuming commonly insects (other arthropods, protozoans and animals may also be trapped)

What 2 types of cells do B-cells differentiate into?

Plasma and memory

Macroplastic debris

Plastic particles larger than 1mm that are a marine pollutant

Microplastic debris

Plastic particles smaller than 1mm that are a marine pollutant

Active Site

Pocket or groove on an enzyme that binds to substrate (i.e. the spot on the enzyme where reaction occurs)

What are the 3 key stages in sexual reproduction in plants?

Pollination, fertilisation and seed dispersion

Pollutant

Pollutant is a contaminant that causes adverse change to an ecosystem or environment

Skin colour determination (8)

Polygenic inheritance More than 2 genes contribute Due to amount of melanin Combination of alleles determine phenotype Continuous variation of colour Phenotypes do not follow Medelian ratios Environment affects gene expression More recessive alleles there are, the lighter the colour

What is PCR?

Polymerase chain reaction - artificial method of DNA replication used to rapidly copy sequences

What does magnesium do?

Poor growth + yellow leaves

Top-down limiting factors

Population growth pressures applied by other organisms at higher trophic levels, e.g. predation

What 2 things does the xylem lining contain?

Pores and pits

inactive phytochrome

Pr

Fossils

Preserved remains of once-living organisms

What are the four levels of structure in a protein?

Primary, secondary, tertiary, and quaternary

competitive exclusion principle

Principle stating that no two species competing for the same resource can coexist indefinitely. So only one species can occupy a niche in an ecosystem

Exocytosis

Process by which a cell releases large amounts of material

convergent evolution

Process by which unrelated organisms independently evolve similarities when adapting to similar environments

crossing over

Process in which homologous chromosomes exchange portions of their chromatids during meiosis.

genetic engineering

Process of making changes in the DNA code of living organisms

What 3 main sections does a gene sequence have?

Promoter (transcription initiation site), coding sequence (the region transcribed) and terminator (transcription termination site)

Give examples of protein utilization in industry

Proteins produced by cultured cells in fermenters are used in: -foods -pharmaceuticals -other products (enzymes in cleaning agents etc.)

Aerobic respiration (7)

Pyruvate fully oxidised By link reaction and krebs cycle Reduced NAD passes electrons to ETC H+ gradient generated Oxygen required as terminal electron acceptor Proton gradient used by ATP synthase to produce ATP Mitochondria and cytoplasm Can use fats and proteins

3 main stages of the link reaction

Pyruvate transported from cytosol to mitochondrial matrix, pyruvate oxidised to produce a reduced carrier (NADH), pyruvate decarboxylated to form acetyl CoA (CO2 produced)

Transcription (11)

RNA polymerase Binds to promotor region on DNA Unwinding of DNA strands Binding nucleoside triphosphates To antisense strand of DNA As it moves along in 5' to 3' direction Using complimentary base pairing Losing 2 phosphates to gain required energy Until terminator signal reached (in prokaryotes) RNA detaches from template and DNA rewinds RNA polymerase detaches from DNA

Lollipop experiment

Radioactive carbon-14 is added to a 'lollipop' apparatus containing green algae (Chlorella)

Hemophilia (13)

Recessive trait Sex linked Gene is on X chromosome Sex chromosomes in females are XX and XY in males Y chromosomes do not have the allele Males inherit X chromosome from their mother Allele is not masked for males Males have a 50% chance Carrier is heterozygous for the gene Dominant allele masks recessive allele Females inherit 1 chromosome from mother, one from father Hemophiliac males have carrier daughters Hemophilia allele could be inherited from either parent

When linked genes cross over what is the new combination called?

Recombinant

What does Nitrogen do?

Reduced growth

What does phosphorus do?

Reduces root system

Biome

Regions of similar climate and dominant plant types (i.e. a type of ecosystem)

pancreas

Regulates the level of sugar in the blood

What do nucleosomes help with?

Regulating transcription in eukaryotes

What is diastole?

Relaxation of the heart

Telomeres

Repeated DNA sequences at the ends of eukaryotic chromosomes.

anaerobic respiration

Respiration in the absence of oxygen.

aerobic respiration

Respiration that requires oxygen

What is the role of type II pneumocytes and how are they adapted?

Responsible for the secretion of pulmonary surfactant creating a moist surface that reduces surface tension (prevents sides of alveoli from adhering to each other)