Question 1

Which of the following best describes the difference between the sugars found in DNA and RNA?

Accepted Answer

DNA contains deoxyribose, which has an H at the 2' carbon; RNA contains ribose, which has an OH group at the 2' carbon.

Question 2

Which nitrogenous base is found only in RNA and not in DNA?

Accepted Answer

Uracil

Question 3

What type of bond links adjacent nucleotides in a nucleic acid polymer?

Accepted Answer

Phosphodiester bond

Question 4

In a double-stranded DNA molecule, which base pairs with guanine, and how many hydrogen bonds are formed between them?

Accepted Answer

Cytosine; 3 hydrogen bonds

Question 5

Which of the following statements about the structure of DNA is correct?

Accepted Answer

The two strands are antiparallel, one running 5' to 3' and the other 3' to 5'.

Question 6

Which of the following is a function of the plasma membrane in cells?

Accepted Answer

It separates the intracellular and extracellular environments.

Question 7

A cell is observed to have a large number of mitochondria. Which of the following is the most likely function of this cell?

Accepted Answer

Rapid contraction requiring high energy

Question 8

Which organelle is primarily responsible for the synthesis of lipids and detoxification of poisons?

Accepted Answer

Smooth endoplasmic reticulum

Question 9

The endosymbiotic theory explains the origin of which organelle(s) in eukaryotic cells?

Accepted Answer

Mitochondria and chloroplasts

Question 10

Which of the following best explains why cells are generally small in size?

Accepted Answer

Smaller cells have a higher surface area to volume ratio, facilitating efficient diffusion of materials.

Question 11

A muscle cell requires rapid contraction and high energy. Which organelle would you expect to be especially abundant in this cell?

Accepted Answer

Mitochondria

Question 12

Which of the following is NOT a function of membrane proteins?

Accepted Answer

Synthesis of DNA

Question 13

Which of the following molecules can most easily pass through the hydrophobic core of a cell membrane?

Accepted Answer

Small nonpolar molecules

Question 14

If a cell has a high concentration of calcium ions inside, what effect does this have on the diffusion of calcium ions across the plasma membrane?

Accepted Answer

Calcium ions will diffuse out of the cell.

Question 15

Which equation correctly represents the surface area to volume ratio for a spherical cell of radius $$r$$?

Accepted Answer

$$\frac{4\pi r^2$}{\frac{4}{3}\pi r^3$}$$

Question 16

Which process is responsible for the movement of glucose into cells via the Glut4 protein?

Accepted Answer

Facilitated diffusion

Question 17

Which of the following statements about the fluid mosaic model of cell membranes is correct?

Accepted Answer

Membrane proteins and lipids can move laterally within the layer.

Question 18

Which organelle is responsible for packaging and distributing proteins and lipids throughout the cell?

Accepted Answer

Golgi apparatus

Question 19

Which of the following is a real-world example of endosymbiosis in eukaryotic cells?

Accepted Answer

A eukaryotic cell containing mitochondria that originated from an ancestral aerobic bacterium

Question 20

Which of the following best describes the role of lysosomes in cells?

Accepted Answer

They break down macromolecules, bacteria, and damaged organelles.

Nucleic Acids: Structure, Function, and Types

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