Biology Answers

Describe three hypotheses proposed to account for the decline in cell numbers during the

death phase of a growth curve

Write down an algorithm for MSA. You have three protein Sequences, for

example SEQ 1:MAKYPW, SEQ 2:MKYTW and SEQ 3:MKYVW. Point Out

conserved region by aligning theses sequences.

A colorimeter is an instrument used for chemical analysis by comparing a liquid’s color with standard colors. In an experiment, a scientist used two colorimeters and noted the readings. The first colorimeter showed consistent readings that were five points lower than the actual reading. The second colorimeter provided readings that were the same as the actual reading. Which two statements are implications of these readings?

Destroying the Trojan horse. Penicillin is hydrolyzed and thereby rendered inactive by penicillinase (also known as ?-lactamase), an enzyme present in some resistant bacteria. The mass of this enzyme in Staphylococcus aureus is 29.6 kd. The amount of penicillin hydrolyzed in 1 minute in a 10-ml solution containing 10-9 g of purified penicillinase was measured as a function of the concentration of penicillin. Assume that the concentration of penicillin does not change appreciably during the assay. (How do you use the Michaelis-Menten equation without Vmax or Km?)

5. replicate the ff. segments of DNA 5' ATCGGCGTTCAC 3' 3' TAGCCGATGCAA 5' a. show the direction of replication of the new strands and explain b. explain how this is semiconservative replication. are the new strands identical to the original segment of DNA? 20 pts

Production of recombinant proteins in microbial bioreactors

Write a letter to a friend who is thinking of going on a questionable “fad” diet. Convince them that this is a very bad idea.

define all the cell organelles with their discovery.

a) Based on the class consensus model of natural selection what will happen to the

snail popluation over 20 generations on the island, assuming the conditions on the

island do not change?

To demonstrate your answer create a representation that shows what happens to the

banded and unbanded snails in the current population, at the first generation, at the

10th generation and the 20th generatio

The Ras protein functions as a molecular switch that is set to its “on” state by other proteins that cause it to release its bound GDP and bind GTP. A GTPase-activating protein helps reset the switch to the “off” state by inducing Ras to hydrolyze its bound GTP to GDP much more rapidly than it would without this encouragement. Thus, Ras Works like a light switch that one person turns on and another turns off. You are studying a mutant cell that lacks the GTPase-activating protein. What abnormalities would you expect to find in the way in which Ras activity responds to extracellular signals?