Question 1 essay writing-just one page

part A

Nitric oxide is involved in firefly flashing. Studying this could provide information to help us understand the action of nitric oxide in other systems. What processes are regulated in humans by nitric oxide? Look online and find a few. Give some examples.

part B

In what way would understanding python digestion mechanisms help humans?

   Read the paper on python digestive physiology (python digestion paper 1 on Blackboard)
• Write a page IN YOUR OWN WORDS about what changes after meals and how understanding it better could help us (and why).

Prediction the phenotype of lambda phage-infected bacteria conferred by the mutations described in the following. Explain your reasoning.

a. A mutation creating a protease-resistant λ CII protein.

b. A mutation of λ O_R2 that will prevent protein binding.

c. A mutation that inactivates the λ N gene.

d. A mutation in the gene encoding the λ CI protein.

Bacteriophage Lambda phage have the ability to survive either as a lysogen w/in a bacterial host or by lytic growth. Lytic growth involves replication of the viral DNA manyfold, assembly of bacteriophage particles, and cell lysis to release the new infectious bacteriophage particles. The bacteriophage particles can each package one entire viral genome of ~50Kb but not much more DNA than that. Use your knowledge of the regulation of the lambda gene expression to design a lambda cloning vector. The cloning vector should be replicated manyfold, and assemble into infectious viral particles that are released by lysis of the host bacterial cell. Hint: think about what genes are necessary for lysogenic growth and dispensable for lytic growth. These are the genes that you can replace with your DNA of interest.

Each year, many people get a flu shot to protect themselves from the flu. Why give flu shots rather than "booster" injections? Why is last year’s flu shot ineffective against this year’s flu? As a class, discuss which of the following methods would be the best type of vaccination for fending off the flu, and explain your reasoning: A. IM (intramuscular) Injection B. Nasal Spray C. ID (intradermal) injection

Gene X encodes a repressor that represses gene Y, which also encodes a repressor. Both X and Y negatively regulate their own promoters. (a) At time t=0, X begins to be produced at rate β, starting from an initial concentration of X=0. What are the dynamics of X and Y? What are the response times of X and Y? Assume logic input functions, with repression thresholds Kxx, Kxy for the action of X on its own promoter and on the Y promoter and Kyy for the action of Y on its own promoter. (b) At time t=0, production of X stops after a long period of production, and X concentration decays from an initial steady-state level. What are the dynamics of X and Y? What are the response times of X and Y?

Gyrate atrophy is a degeneration of the retina that begins in late adolescence as night blindness and progresses to blindness. The cause is mutation in the gene that encodes a mitochondrial enzyme, ornithine aminotransferase (OAT), on chromosome 10. This autosomal recessive inborn error of metabolism causes build up in body fluids of ornithine, which derives from the amino acid arginine, found in dietary protein. Researchers sequenced the OAT gene for five patients with the following results:

Patient A: A change in codon 209 of UAU to UAA

Patient B: A change in codon 299 of UAC to UAG

Patient C: A change in codon 426 of CGA to UGA

Patient D: A 2 base deletion at codons 64 and 65 that results in a UGA codon at position 79

Patient E: Exon 6, including 1,071 bases, is entirely deleted.

1. Another patient, F, has the mutations seen in patients A and B. How is this possible?

Organisms use different sources of carbon and energy. Archaeans do NOT use glycolysis and do NOT always use the pentose phosphate pathway, but use variations on these pathways for similar purposes. What is the best classification of this type of catabolism?

Choose the best answer.

A. Chemolithotrophs

B. Chemoorganotrophs

C. Photoheterotrophs

D. Photoautotrophs

What features did the cells you observed have in common? How were they different? - Bacillus Megaterium - Mixed Diatoms - Anaboena - Micrococcus Luteus - Hydra - Saccharomyces - Paramecium

Describe one experimental method used to identify regulatory elements and their domains of regulation (e.g. which tissues are they activated in)

The K+ concentration inside a nerve cell is found to be 20x higher outside the cell than inside the cell, while the Na+ concentration is 20x higher inside versus outside. A. If the membrane potential Em (Ein-Eout) is -77.6 mV, identify the ion that must be transported actively versus the ion that is near equilibrium (assuming ideal conditions). B. The NA+ -K+ -ATPase (or sodium-potassium pump), moves three sodium ions from inside to outside, and two potassium ions from outside to inside while simultaneously hydrolyzing ATP to ADP + Pi. If ATP/ADP is 40 and [Pi] is 25mM, estimate the change in potential (∆µ kJ/mol) for the sodium transport, potassium transport and ATP to ADP + Pi separately (assuming ideal conditions). C. A researcher proposes that perhaps a single ATP hydrolysis is sufficient for two rounds of Na+ /K+ exchange (i.e., move 6 Na+ atoms out and 4 K+ atoms in). Is the hydrolysis of a single ATP sufficient to account for the active transport of ions for a single cycle? For two? Assume ideal conditions & Justify your answer. D. Now imagine we are in non-ideal conditions, and the ionic strength on the inside of the cell is much higher than outside the cell. Considering only the sodium export, will this export be more or less favored when compared to the ideal scenario (Justify your answer)

a) The discovery of ribozymes led to the theory that the evolution of life on Earth began with an “RNA world.” Describe how the current cellular roles of RNA support this theory.

b) Draw a diagram of the transcription and translation of the trp operon under high tryptophan conditions. In addition to the trp operon, show RNA polymerase; the 5` UTR RNA with regions 1, 2, 3, 4, and the string of uracils; and a ribosome.

In a high elevation lake in Peru lives a population of guppies. There are 75 guppies in this lake, 60 of which have blue tails, while the remaining 15 have yellow tails. Tail color in guppies is controlled by a single gene. Which of the following statements about this population of guppies is true?

Beech Bark Disease is a (mostly) fungal disease that was first observed in the US in NYC in the 1950's and is spreading south. It kills mature trees in as little as 5 years. As it spreads through the UGA Botanical Garden, the size of the beech population is reduced by 98%, leaving only the 2% of individuals that exhibit some resistance to the fungus. Over time the population increases to its original size. All of the individuals in the new population exhibit resistance to the fungus, but are more susceptible to root rot disease.

This story is an example of: (Mark all that apply or are described directly)