Question 1

Which structural feature of a phospholipid, as shown in the diagram, is responsible for the formation of a kink in one of the hydrophobic tails?

Accepted Answer

Presence of a cis double bond in the fatty acid tail

Question 2

Based on the DNA diagram, which type of chemical bond is responsible for holding the two strands of DNA together?

Accepted Answer

Hydrogen bonds between complementary base pairs

Question 3

In the phospholipid diagram, which component is directly responsible for the molecule's amphipathic nature?

Accepted Answer

Hydrophilic head and hydrophobic tails

Question 4

According to the DNA diagram, what is the directionality of the two strands in a DNA double helix?

Accepted Answer

Antiparallel, with one strand running 5' to 3' and the other 3' to 5'

Question 5

Which part of the phospholipid molecule, as shown in the diagram, interacts with water molecules in an aqueous environment?

Accepted Answer

Hydrophilic head

Question 6

In the DNA diagram, which base pairs are shown to be joined by hydrogen bonds?

Accepted Answer

Adenine with Thymine and Guanine with Cytosine

Question 7

What is the primary function of the kink caused by the cis double bond in the fatty acid tail of a phospholipid?

Accepted Answer

To increase membrane fluidity by preventing tight packing of phospholipids

Question 8

Which chemical group in the phospholipid diagram is most likely to participate in cell signaling?

Accepted Answer

Choline group

Question 9

According to the DNA diagram, which structural feature ensures the stability of the DNA double helix?

Accepted Answer

Sugar-phosphate backbone

Question 10

If a mutation causes the loss of the cis double bond in a phospholipid's fatty acid tail, what is the most likely effect on membrane properties?

Accepted Answer

Membrane becomes less fluid and more tightly packed

Foundations of Biology: Structure, Chemistry, and Cell Organization

Study Guide - Practice Questions