Question

the interior part of the bilayer in a cell membrane is_.

a hydrophobic

b hydrophilic

question 61

penicillin is effective against gram - bacteria.

a positive

b negative

question 62

what is an example of a mutation in an allele?

a a base change in the gene coding sequence

b a base change in the genes regulatory regions

c a deletion of a base within the gene

d an insertion of a base within the gene

e all of the above.

Explanation:

• Question 60: Cell membranes are composed of a phospholipid bilayer. Phospholipids have hydrophilic (water - loving) heads and hydrophobic (water - fearing) tails. The interior of the bilayer is made up of the tails, so it is hydrophobic.
• Question 61: Penicillin works by inhibiting the synthesis of the peptidoglycan layer in the bacterial cell wall. Gram - positive bacteria have a thick peptidoglycan layer, making them more susceptible to penicillin.
• Question 62: A mutation in an allele can occur in various ways. A base change in the gene coding sequence (missense, nonsense mutations), a base change in the regulatory regions (can affect gene expression), a deletion of a base (frameshift mutation if not in multiples of 3), and an insertion of a base (also can cause frameshift mutation if not in multiples of 3) are all types of mutations in alleles.

Answer:

• Question 60: A. hydrophobic
• Question 61: A. positive
• Question 62: E. All of the above.