Metabolism
If ΔG is negative, this is what type of reaction?
Exergonic (spontaneous)
Name the two types of fermentation that can occur after glycolysis in the absence of oxygen.
Lactic acid fermentation and alcohol fermentation
Is photosynthesis anabolic or catabolic?
Anabolic
Why does polymerase chain reaction (PCR) use a special polymerase (Taq polymerase)?
Taq polymerase comes from thermus aquaticus bacteria that are found in geysers (really high temperatures). This is used because Taq polymerase (as opposed to most other polymerases) can withstand the first step of denaturation at high temperature (~95 degrees C) to separate the DNA strands into single stranded DNA. It is also important not to cool the DNA down to a temperature at which the DNA strands would reattach to each other, so the optimal temperature of ~70 degrees C at which Taq polymerase works is ideal.
What cell lines do mitosis and meiosis occur in respectively?
Mitosis- somatic cells
Meiosis- germ line cells
Name an environmental condition that could denature an enzyme.
pH, temperature
Name the 4 steps of cellular respiration.
Bonus for 2x the points: which step does not produce any ATP?
Glycolysis, pyruvate oxidation, citric acid cycle ( AKA Krebs cycle or TCA cycle), oxidative phosphorylation
Bonus: Pyruvate oxidation
Where do the light and dark reactions occur in the chloroplast?
Light reactions- thylakoids
Dark reactions/Calvin cycle- stroma
Name one way in which DNA replication accuracy is maintained.
Proofreading by the polymerase itself, or mismatch repair that uses nuclease, polymerase, and ligase to repair damaged DNA (ex: thymine dimer from UV damage)
List the phases of Mitosis in order.
Interphase, prophase, metaphase, anaphase, telophase, cytokinesis
What is the main effect of adding an enzyme to a chemical reaction?
They lower the activation energy
What is the main carbon molecule produced by glycolysis?
Pyruvate (2)
Name two molecules that are regenerated during during the Calvin cycle?
Bonus- 100 pts: what is the main output of the calvin cycle?
RuBP, ADP, NADP+
Bonus: G3P
Why does DNA polymerase have a more difficult time replicating on the lagging strand? What does it do to remedy this?
DNA polymerase is only able to add dNTPs complimentary to the template strand in the 5' to 3' direction. Therefore, as helices unwinds the DNA, the lagging strand will need primase to add RNA primers to the newly exposed DNA and will move in short increments as the DNA unwinds. These short segments of DNA with their primers are called Okazaki Fragments.
In what phase of meiosis does recombination occur?
Prophase I
Name 2 molecules that allow cells to undergo energy coupling and overcome a positive ΔG (endergonic reaction).
ATP, FADH, GTP, NADH, NADPH, etc. (AKA either phosphate donors or electron carriers)
What is the main purpose of the citric acid cycle?
To generate A LOT of reducing power in the form of NADH and FADH2 in order to use them during oxidative phosphorylation to produce ATP
More specifically, this occurs every time a CO2 molecule is released (energy released) from the larger carbon molecule (6C to 5C to 4C) and then after rearrangements of the 4C molecule, releasing further energy
Acetyl (2C from pyruvate oxidation AcetylCoA) added to a 4 carbon molecule to make the initial 6C molecule
During the light reactions, where do the electrons for the electron transport chain come from?
H2O (gets oxidized to O2)
In the Hershey-Chase experiment, explain why/how radioactive sulfur and phosphorus were used?
Bacteriophages grown in radioactive sulfur (stains protein) injected their "genetic material" into bacteria, and once it was centrifuged, the bacterial pellet had no color. Phages grown in radioactive phosphorus (stains nucleic acids) injected their genetic material into bacteria, and the bacterial pellet was bright blue. Therefore, the genetic material was confirmed to be nucleic acids.
List the phases of the cell cycle and briefly describe each step in a few words.
Interphase- G1- growth, metabolism, S- DNA synthesis (replication before cell division), G2- growth, metabolism
Mitotic Phase (M)- Mitosis- duplicated chromosomes divide into two cells, cytokinesis (cells actually divide via cleavage furrow in animals and cell plate in plants)
List 3 ways an enzyme can be regulated.
Feedback inhibition, competitive inhibitor, noncompetitive (allosteric) inhibitor, gene expression, localization to part of the cell, activator
During oxidative phosphorylation, what does the electron transport chain power?
proton pumps (pumps protons across the inner membrane of the mitochondria to create an electrochemical gradient or proton motive force to power ATP synthase)
What is the purpose of Rubisco in the calvin cycle?
It catalyzes the covalent addition of CO2 to RuBP to make an unstable 6 carbon sugar molecule that will split into two 3 carbon molecules
In the Meselson-Stahl experiment where bacteria were cultured in 15N medium followed by 14N medium and then centrifuged to separate the DNA, what results seen in the centrifuge after the first and second replication indicated that the semiconservative model is correct?
Describe the difference between the law of segregation and the law of independent assortment.
The law of segregation states that every individual possesses two alleles and only one allele is passed on to the offspring. The law of independent assortment states that the inheritance of one pair of genes is independent of inheritance of another pair.