BIOL 121 EXAM 1 PURDUE
Homo sapiens
homo - genus sapins - name of species
Prophase 1
homologous chromosomes pair and form tetrad protein complex forms that holds tetrad pairs together crossing over -chromatids exchange genetic info
Anaphase 1
homologous pairs separate each cell gets 1 kind of chromosome
Nucleic Acid Function
information storage and transfer synthesis of proteins transfer chem energy (ATP) RNA enzyme/regulator -microRNA
Mitosis Steps
interphase, prophase, metaphase, anaphase, telophase, cytokinesis IPMAT
Capturing Light
light - photons(packets of energy) E ~ 1/wavelength energy is absorbed and passed to rxn center
2 Stages of Photosynthesis
light reactions and dark reactions
Steroids
lipids characterized by a carbon skeleton consisting of four fused carbon rings. Testosterone
Secondary Protein Structure
localized twisting or folding alpha helices and beta pleated sheets
Cholesterol
made in liver and degraded in liver LDL (Low Density Lipoprotein) - delivery trucks, bad, dilivery cholesterol directly to the cells HDL (High Density Lipoprotein) - good, garbage trucks, moving excess cholesterol to the liver, which turns it into bile
Poikilothermic
maintaining the body at the same temperature as the environment "Cold blooded" animals
Saturated Fatty Acids
max number of H atoms possible pack tightly + cholesterol = heart disease
Telophase
membrane returns cytokinesis - cytoplasm divides get two identical cells
Lipid Function
membrane structure energy storage structural basis for animal hormones & vitamins
Light Reaction
need light and it produces oxygen as a by product 2H2O + light -> O2 + 4[H+] + 4e-
Amniocentesis
needle puncture of the amniotic sac to withdraw amniotic fluid for analysis
Telophase 1
new haploid nuclei(still have 2 chromatids) 1/2 # of chromosomes
Dark Reaction (Calvin cycle)
no light needed CO2 reduced to sugars CO2 + 4[H+] + 4e- -> CH2O + H2O
Glucose
oxidized in small steps to release ATP. ATP/Redox reaction; transfer of electrons
Protein Structure Levels
primary, secondary, tertiary, quaternary
Enzyme
protein that acts as a biological catalyst reacting in small amounts lower Ea (energy of activation) DOES NOT affect the free energy change in G
Meiosis
reduction division process, occurring only in reproductive cells, in which one diploid (2n) cell produces four haploid (n) cells that are not genetically identical
Interphase 1
replicate DNA
Monosaccharides
ribose, glucose, glyceraldehyde simple sugars
C4 Plants
separation of fixation of CO2 & making sugar CO2 + PEP gives oxaloacetate PEP has high affinity for CO2 When temperature is high and light is intense, stomata is closed. CO2 concentration drops, and oxygen concentration increases (photosynthesis). O2 outcompetes CO2 for RuBP. O2+ RuBP -> photorespiration (wasteful process, no ATP)
Primary Protein Structure
sequence of amino acids in a polypeptide chain -inherited
Carbohydrate function
source of energy stored energy structural components
Prophase 2
spindle apparatus forms
Polysaccharides
starch and multiple sugars easily broken down by enzymes
Carbohydrates
starches and sugars
Protein Function
support - collagen, virus coats, tendons transport - hemoglobin movement - actin, myosin defense - antibodies enzymatic - regulate chem rxns (speed them up)
Metaphase 1
tetrads line up on equatorial plate spindle fibers attach
Phospholipids
two fatty acids + phosphate group + glycerol membrane function
Prokaryote
unicellular Asexual reproduction none/few organelles circular chromosome single membrane bacteria and archaea
How do crossing-over and independent assortment increase the genetic variability of a species? At what stage during meiosis do each of these processes occur?
(Prophase I) Crossing-over is the exchange of genetic material between non-sister chromatids of homologous chromosomes. It results in new combinations of genes on each chromosome. (Anaphase I) When cells divide during meiosis, homologous chromosomes are randomly distributed during anaphase I, separating and segregating independently of each other. This is called independent assortment. It results in gametes that have unique combinations of chromosomes. All of these mechanisms working together result in an amazing amount of potential variation. Each human couple, for example, has the potential to produce more than 64 trillion genetically unique children.
ATP
(adenosine triphosphate) main energy source that cells use for most of their work ATP + water = Pi + 7.3 kcal/mol
Anaphase
- chromatids separate (new chromosomes) - move to opposite ends
Levels of Asexual Genetic Variability
- little to no variation (mutations cause small changes in DNA) 2. Conjugation - transfer DNA segments 3. Transformation -have ability to absorb DNA from surroundings 4. Transduction -viruses that attack bacteria carry DNA bck/frth
Metaphase
- spindle fibers attach to centromere - 2 chromatids line up on equatorial plane
Levels of Sexual Genetic Variability
-mutate at a low rate 1. Independent Assortment of chromosomes -2^n combos (n = haploid #) 2. Crossing over 3. random fertilization
CAM plants
-separation of process in time -open stomates at night for carbon fixation to make C4 compounds - close stomates during day to conserve water Desert plants, pineapples
Prophase
-spindle apparatus forms -nuclear membrane disappears
Characteristics of Abnormal Cell Division
1. Activation of oncogenes doesnt work 2. Tumor Suppressor Genes dont work 3. HeLa Cells - limitless reproductive potential 4. Tumor angiogenesis - capacity to supply blood 5. Metastasis - can migrate to other organs
Dark Reaction (Calvin Cycle Steps)
1. Fixation of C - 6CO2 + 6RuDP -> 12PGA (catalyzed by rubisco) 2. Reduction - 12ATP + 12NADPre -PGA -> PGAL (2 PGAL = 1 glucose) 3. Regenerate RuBP - 6 RuMP + 6 ATP -> 6 RuBP - costs: 18 ATP & 12 NADPre
Cell Cycle
1. Gap 1 -single unreplicated chromosome -period of synthesis and growth -regulatory molecules -is cell ready to divide? -if not - Gnought (common in nerve cells) 2. Synthesis Phase -replicate genetic material -2 chromatids 3. Gap 2 -make proteins 4. Mitosis
Light Reaction Steps
1. P680 gets a photon of light 2. e- go to primary e- acceptor (pheophytin). [Electron into pheophytin.] 3. Split water to replace electrons (byproduct of O2) 4. e- go down PSII, generate ATP (another light rxn) 5. e- fill "e- hole" in P700 after getting photon 6. e- passed down PSI 7. e- reduce NADox -> NADre
How do we know which molecules to use?
1. Universally distributed 2. Functionally similar 3. Homologous parts 4. Changes at a rate commensurate with evolutional distance --Broader the distance between two things, the slower the rate of change needed
What estimates have been made for the number of species on Earth, and how accurate are they?
1.9 million species have been identified, but total diversity of about 8.7 million species is estimated.
How many species?
1.9 million species. Total diversity of 8.7 million species. (1/2 live on about 6% of rain forests.
Diploid
2 sets of chromosomes
Binary Fission
A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size
Action Spectrum
A graph that profiles the relative effectiveness of different wavelengths used in photosynthesis
Fragmentation
A means of asexual reproduction whereby a single parent breaks into parts that regenerate into whole new individuals.
Respiration
ATP synthesis C6H12O6 + 6O2 -> 12H2O + 6CO2 + energy 4 steps -glycolysis -oxidation (loss of e-) of pyruvic acid to acetyl CoA -Krebs Citric Acid Cycle -Respiratory Electron Transport Chain
Nondisjunction
An error in meiosis or mitosis in which members of a pair of homologous chromosomes or a pair of sister chromatids fail to separate properly from each other.
Haploid
An organism or cell having only one complete set of chromosomes.
Budding
Asexual reproduction in which a part of the parent organism pinches off and forms a new organism
Parthenogenesis
Asexual reproduction in which females produce offspring from unfertilized eggs.
After arriving at a 5 kingdom classification scheme, for what reasons did biologists propose the 6 kingdom and then the 3 domain classifications schemes? Which kingdoms contain unicellular organisms, and which multicellular?
Before 1969 - life was classified into two kingdoms: Plant Kingdom and Animal Kingdom. In 1990 Carl Woese: finding evidence for a group of unknown prokaryotic organisms that can live in extreme environments - 3rd Domain of life (Archaea) NOW: Bacteria, Archaea, and Eukarya. From 1969-1990 - Life was classified into 5 Kingdoms based on anatomy, morphology, embryology, and cell structure.
Asexual Reproduction types
Binary Fission, Budding, Fragmentation, Vegetative Reproduction, Parthenogenesis
Lipids
C, H, O fats, oils, waxes
Proteins
C, H, O, N - ALWAYS! Sometimes P, S, Mg, Fe Polymer using 20 amino acids, Count the number of amino acids that are different or similar. Tape measurer of evolution Species that share more traits are similar
Nucleic Acids
C,H,O,N,P - ALWAYS! polymers of nucleotides nitrogen base, pentose sugar, phosphate group
Meiosis
Cell division that produces reproductive cells in sexually reproducing organism
Interphase
Cell grows, performs its normal functions, and prepares for division replicates chromosomes "sister chromatids G1, S, and G2
Metaphase 2
Chromosomes line up at the equator.
History of Photosynthesis
Correct Assumptions: -C incr due to CO2 -N in plants is from soil -plants require light & chlorophyll to incr dry weigh -plants give O2 in day & CO2 in dark -plants respirate 24/7, photo synth in light -splitting of H2O Incorrect Assumptions -CO2 split to give oxygen
DNA and RNA
DNA -deoxyribose -A-T, G-C -double helix RNA -ribose -A-Uracil, G-C -single helix
Systematics
Evolutionary and genetic relationships between organisms.
Final Energy Totals
Glycolysis: 2 ATP + 2 NADre(1.5 ATP ea) = 5 ATP Pyruvate > Acetyl CoA: 2 NADre + 2.5 ATP = 5 ATP Kreb's: 2 ATP + 6 NADre + 2 FADre = 20 = 30 ATP = 7.3 Kcal = 219 Kcal
How are the different methods of nutrition represented among the various kingdoms? Domains?
Heterotrophic vs Autotrophic vs Both
Respiratory Electron Transport Chain
High energy electrons from NADre and FADre to a large protein complex. Oxygen = final electron acceptor. Energy is used to create a chemioosmotic gradient. NAD/FAD transfer e-/hydrogen to O2 NADre = 2.5 ATP FADre = 1.5 ATP
Meiosis Steps
Interphase 1, Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, Interkinesis, Prophase 2, Metaphase 2, Anaphase 2, Telophase 2
Tree of Life
Kingdom/Phylum/Class/Order/Family/Genus/Species
Fermentation includes glycolysis and steps to regenerate NADox. Where does fermentation occur in the cell? How does fermentation differ between fungi and animals?
Lactic acid fermentation occurs in bacteria, fungi, and animal muscle cells. It's a pretty simple follow-up to glycolysis: the pyruvate molecules are reduced to lactate, while NADH is oxidized to NAD+. In this way, NAD+ is replenished and cycles back through glycolysis. Alcohol fermentation is pretty similar to lactic acid fermentation. Instead of the pyruvate being reduced to lactate, it's reduced to ethanol and lets off two molecules of CO2 along the way. Two kinds of organisms can do alcohol fermentation: bacteria and yeast (yeast, by the way, are fungi). Fermentation reactions occur in the cytoplasm of both prokaryotic and eukaryotic cells. In the absence of oxygen, pyruvate does not enter the mitochondria in eukaryotic cells.
Why are macromolecules described as polymers? What are polymers composed of?
Most large biological molecules are polymers, long chains made up of repeating molecular subunits, or building blocks, called monomers. If you think of a monomer as being like a bead, then you can think of a polymer as being like a necklace, a series of beads strung together. Because of their polymeric nature and their large (sometimes huge!) size, they are classified as macromolecules, big (macro-) molecules made through the joining of smaller subunits. Carbohydrates, nucleic acids, and proteins are often found as long polymers in nature.
Glycolysis
NO OXYGEN NEEDED! anaerobic breakdown of glucose to pyruvic acid all organisms happens in cytosol Using 2 ATP and producing 4 ATP = NET of 2 ATP and 2 NADre-(1.5 ATP ea)
Redox Reaction
Oxidation - loss of electrons Reduction - gain of electrons OIL RIG
Interkinesis
Period of time between meiosis I and meiosis II during which no DNA replication takes place.
Describe the cell walls of organisms in the Plantae, Fungi and Animalia kingdoms.
Plantae: Plant cell walls prevent enlargement of the plant cell and play important roles in the absorption, secretion and transport of substances within the plant. They consist mainly of intertwined cellulose microfibrils. This cellulose framework is penetrated by an arrangement of non-cellulose molecules. Other substances present in some plant cell walls include lignin, a strong rigid molecule that provides support, and suberin cutin waxes, fatty substances on the outside of plants that prevent water evaporation and plant dehydration. Fungi: fungal cell walls contain chitin rather than cellulose. Chitin is a tough, semitransparent and complex molecule made up of repeating units of a sugar called acetylglucosamine. It is better known as the substance that makes up the hard outer coating of crayfish, crabs, lobsters and some insects. Animalia: Animal cells lack a cell wall entirely
Homeothermic
Refers to an organism's ability to maintain a constant body temperature despite variations in environmental temperature. "warm-blooded" animals
Photorespiration
RuBP + O2 instead of RuBP + CO2 produces CO2 and no ATP
How does the light absorption by PS II contribute to the splitting of water? How does the splitting of water contribute to ATP production?
The light-dependent reactions begin in photosystem II. Light energy splits water and extracts electrons in photosystem II (PSII); then electrons are moved from PSII to cytochrome b6f to photosystem I (PSI) and reduce in energy. In non-cyclic photophosphorylation, cytochrome b6f uses the energy of electrons from PSII to pump hydrogen ions from the lumen to the stroma; this energy allows ATP synthase to attach a third phosphate group to ADP, which forms ATP. In cyclic photophosphorylation, cytochrome b6f uses the energy of electrons from both PSII and PSI to create more ATP and to stop the production of NADPH, maintaining the right proportions of NADPH and ATP.
Phosphorylation
The metabolic process of introducing a phosphate group into an organic molecule. produces ATP for transport (regeneration) ADP + Pi + energy -> ATP + H2O
What form of chemical bond characterizes each level of protein structure? What role does a protein structure play in its function?
The primary structure of a protein consists of amino acids chained to each other. Amino acids are joined by peptide bonds. (A peptide bond is a type of covalent bond between the carboxyl group of one amino acid and the amino group of another amino acid.) The secondary structure describes the three-dimensional folding or coiling of a chain of amino acids. This three-dimensional shape is held in place by hydrogen bonds. (A hydrogen bond is a dipole-dipole interaction between a hydrogen atom and an electronegative atom, such as nitrogen or oxygen.)
Absorption Spectrum
The range of a pigment's ability to absorb various wavelengths of light.
Taxonomy
The scientific study of how living things are classified. according to a scheme
Compare sexual and asexual reproduction in Chlamydomonas. What prompts sexual reproduction?
Under favorable conditions of growth, Chlamydomonas reproduces asexually; only when the conditions are unfavorable does it reproduce sexually.
What does lactic acid have to do with muscle fatigue? Is this an aerobic process?
When the body taps into anaerobic metabolism, it uses the body's supply of stored sugars, known as glycogen, without the need for oxygen. One of the byproducts of burning glycogen — a process known as glycolysis — is lactic acid. Research has also determined that lactic acid, also known as lactate, is actually an important fuel source for muscles and that the accumulation of lactate does not inhibit the ability of skeletal muscles to contract. Lactic acid is a byproduct of anaerobic metabolism, in which the body produces energy without using oxygen.
Vegetative Reproduction
a form of asexual reproduction in which offspring grow from a part of a parent plant
Krebs Citric Acid Cycle
acetyl CoA + oxaloacetate -> citric acid goes through twice b/c 2 acetyl CoA Net: 4 CO2, 2 ATP, 6 NADre, 2 FADre
Tertiary Protein Structure
additional folding interaction between R groups
Asexual
all genes from single parent exact copies
Hermaphrodite
an organism that has both male and female reproductive organs can mate with others as well as itself - sessile organisms
Fermentation(glycolysis)
anaerobic (alternative) process by which ATP is produced by glycolysis Uses up 2 NADre made in glycolysis
Eukaryote
asexual/sexual reproduction mitosis and meiosis inner & outer membrane organelles no circular chromosome -nucleus: genetic material -mitochondria: power house
Quaternary Protein Structure
association of several polypeptide chains
Telophase 2
cells divide four (1n) daughter cells form membrane forms
Anaphase 2
centromere divides sister chromatids separate
Unsaturated Fatty Acids
double bonds crooked structure liquid
Disaccharide
double sugar sucrose
C3 Plants
efficient at photosynthesis in cool wet climates
Mitosis
eukaryotic cell division
Triglycerides
glycerol + 3 fatty acids Saturated: max # of hydrogen (saturated with H) Unsaturated: min # of hydrogen; double bonds