#1: Gene Transcription and Translation

Write a brief statement hypothesizing as to why mRNA is so unstable in most bacteria (t1/2 of about 1 minute), when the same half-life is more like 1 hour in higher organisms?

6. Aminoacyl-tRNA synthetases catalyses _____ 1. DNA replication 2. transcriptional termination 3. the attachment of amino acids to the tRNA molecules. 4. the binding of mRNA to the 30S subunit. 5. the removal of the polypeptide from tRNA in the P site and transferal to the amino acid at the A site 7. If the strand “5'-TACGCCT-3'” is a template strand, what would the mRNA strand look like? 1. 5'-AGGCGUA-3' 2. 3'-AUGCGGA-5' 3. 3'-ATGCGGA-5' 4. 5'-AGGCGTA-3' 5. 5'-UGGCGTU-3' 8. A repressor is a______. 1. regulatory protein that increases the rate of transcription 2. regulatory protein that binds to DNA and inhibits transcription 3. form of positive control. 4. small effector molecule that causes transcription to increase 5. enzyme that converts lactose to allolactose 9. Complete the following statement: When there is lactose in the medium and no glucose, the cAMP concentration is _____. 1. low 2. medium 3. high 4. inhibited by negative feedback 5. negatively regulated 10. Antisense RNA________ 1. carries a codon during translation 2. is a strand of RNA, complementary to a specific mRNA strand. 3. cleaves RNA into fragments 4. functions in the translation of proteins 5. are sequences that increase gene expression

1) Describe the five basic mechanisms of antibiotic action against bacterial cells. Give examples of drugs that are used in each category.

2) In many instances, resistance builds to antibiotics over time. Describe at least seven ways this resistance develops

Each of the following bacterial lifestyles exposes the bacteria to an environment that requires special evolutionary adaptations to survive. In each case, explain what adaptations were required for the bacteria to live in that environment, and describe how the adaptations allow survival.

A. Thermophiles

B. Microaerophiles

C. Alkalophiles

D. Halophiles

in badgers, fur color is inherited through simple autosomal inheritance, and black fur is dominant to white fur. A black badger is crossed with a white badger. In a cete of four kits, all of the kits are black. You have asked to draw a conclusion about the black badger. What is the best conclusion you can draw from this data? a. The black badger is definitely homozygous. b. the black badger is probably homozygous. c. the black badger is definitely heterozygous. d. the black badger is probably heterozygous. e. the genotype of the black badger cannot be inferred with this information.

Describe the role of specific proteins involved in the muscle contraction process.

Penicillin is an antibiotic that inhibits peptidoglycan synthesis. Based on your results and knowledge of cell envelope differences, would penicillin be more effective against S. aureus (purple) or E. coli (red)? Explain your rationale.

Describe the role of specific proteins involved in the muscle contraction process.

Describe the role of specific proteins involved in the muscle contraction process.

A corn breeder has a plant that is dominant for 4 traits that are known to assort independently (i.e. it’s phenotype is A_ B_ C_ D_). This plant has desirable properties, so the breeder wishes to determine its exact genotype. The breeder performs a test cross and obtains the following results in the F1 generation.

The glutamate side chain has a pKa of 4.4. Calculate the percentage of Glu that is unprotonated at a pH of 4.7.

You hypothesize that a group of tolerogenic cells is located in the fetal pancreas.

a. What method would you use to identify their location within the tissue?

b. What method would you use to quantify their abundance in the whole fetal pancreas based on their surface expression of protein A and Protein B and the absence of protein C?

Protein Code: 1CJY which is HUMAN CYTOSOLIC PHOSPHOLIPASE A2.

Please go in depth about what the structural features are of the protein? (primary, secondary, tertiary, quaternary)

a. You start a culture of stem cells and you use a protocol to differentiate them into beta cells. To make sure they are truly beta cells.
First you want to check whether the insulin gene is expressed at higher levels in the differentiated vs. the undifferentiated cells. What methods that we studies would you use and describe the step by step procedure.

b. Then you want to demonstrate that they secrete insulin when you place glucose in their culture media. What methods that we studies would you use and describe the step by step procedure.

c. Finally, you want to show that inside differentiated cells insulin is located within secretory vesicles and quantify in which percentage of the cells. What methods that we studies would you use and describe the step by step procedure.

Explain how can changing one base in a segment of DNA can make a protein incapable of carrying out its biological role.