Question

You will know if the ant population has reached the carrying capacity (K) of the 2 acre plot when __________.

a) ants are no longer born

b) ants no longer die

c) the ant birth rate equals the death rate

d) there is no longer room for ants to tunnel

e) the birds start eating the ants

As a 4-year old child, your BIOL 1114 instructor contracted mumps, a viral disease. Although he is now middle-aged, he is immune to this disease. Which one of the following is the best hypothesis to explain this observation?

a) The mumps virus can no longer invade his body.

b) He possesses memory cells specific to the mumps virus due to his previous infection.

c) He started to produce more macrophages at age 40 than he did as a child.

d) His DNA mutated as a result of the previous infection with mumps virus.

e) Those morning cups of expresso coffee jump-started his immune system.

The evolution of antibiotic resistance in bacteria is due to which one or more of the following?

a) The antibiotic causes mutations in the bacteria.

b) Natural selection works on the bacteria population.

c) Chance mutations occur in the DNA of the bacteria.

d) Natural selection causes mutations in the bacteria.

e) Both (b) and (c).

Which one or more of the following involve cellular secretion and exocytosis?

a) Your immune system’s B cells fighting off a strep bacterial infection.

b) Neuron communication with muscles in your hand.

c) Macrophages engulfing a TB bacterium by phagocytosis.

d) Both (a) and (b).

e) Both (b) and (c).

If you were handed a sample of DNA and told that it contained 30% guanine (G), which one or more of the following analyses would youadditionally need to do in order to tell someone the exact % composition of ALL the DNA bases?

a) % T

b) % C

c) % A

d) both (a) and (b)

e) No more analysis is necessary.

Answer 1

1) Population growth depends on population size, birth rate, and death rate. In fact, availability of resources determines the growth rate over a period of time. However, most of the population does not grow forever, they eventually run out of resources required. literally, as the growth rate of population decreases the number of individual increases is referred to as logistic growth rate. The carrying capacity (k) of a population is the maximum number of individual environment can support. It is represented by -

dN/dt = rN(K-N/K), where r is the per capita growth which involves the number of birth and death in a population.

Hence, the answer would be c) the ant birth rate equals the death rate

2) Since BIOL 1114 instructor contracted mumps, a viral disease during his childhood, so the first encounter with the antigen would have created memory cells which act instantly with the second encounter with the same antigen and make the individual immune to it.

Hence, the right answer is b) He possesses memory cells specific to the mumps virus due to his previous infection.