Question 1

Which of the following best describes the Central Dogma of Molecular Biology?

Accepted Answer

DNA is transcribed into RNA, which is then translated into protein.

Question 2

Which type of RNA carries amino acids to the ribosome during protein synthesis?

Accepted Answer

tRNA

Question 3

A mutation changes the DNA sequence from $$	ext{TAC} to$$ $$	ext{TAT}. $$What is the most likely effect on the resulting protein?

Accepted Answer

It may result in a silent mutation if the codon still codes for the same amino acid.

Question 4

Which of the following best explains why the plasma membrane is described as 'selectively permeable'?

Accepted Answer

It regulates the movement of certain molecules in and out of the cell based on size, charge, and solubility.

Question 5

During translation, which molecule acts as the template for assembling amino acids into a polypeptide?

Accepted Answer

mRNA

Question 6

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

Accepted Answer

Storing genetic information

Question 7

A scientist stains a cell with methylene blue. Which cellular components will be most visible under the microscope?

Accepted Answer

DNA and RNA

Question 8

Which of the following best describes the tertiary structure of a protein?

Accepted Answer

The folding of the polypeptide chain into a 3-dimensional shape stabilized by interactions between side chains

Question 9

If a cell's surface area increases by a factor of 4, by what factor does its volume increase?

Accepted Answer

$$8 ($$since volume increases with the cube of the linear dimension, while surface area increases with the square)

Question 10

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

Accepted Answer

DNA is a double helix composed of deoxyribose, phosphate, and nitrogenous bases.

Question 11

Which process occurs in the nucleus and involves the synthesis of RNA from a DNA template?

Accepted Answer

Transcription

Question 12

A cell is observed to have a large number of ribosomes attached to its endoplasmic reticulum. What is the most likely function of this cell?

Accepted Answer

Protein synthesis for export

Question 13

Which of the following best describes the role of the Golgi apparatus in the cell?

Accepted Answer

It modifies, sorts, and packages proteins for secretion or delivery to other organelles.

Question 14

Which of the following is a correct pairing of a nitrogenous base in DNA?

Accepted Answer

Guanine pairs with cytosine

Question 15

A patient has a genetic disorder caused by a mutation in the gene coding for a membrane protein. Which cellular process is most likely affected?

Accepted Answer

Transport of molecules across the plasma membrane

Question 16

Which formula correctly represents the relationship between surface area ($$A) $$and volume ($$V) $$for a spherical cell of radius $$r$$?

Accepted Answer

$$A = 4 \pi r^2$, V$$ = \frac{4}{3} \pi $$r^3$$

Question 17

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

Accepted Answer

Smaller cells have a higher surface area-to-volume ratio, allowing efficient exchange of materials.

Question 18

Which of the following is a function of carbohydrates in the cell membrane?

Accepted Answer

Providing structural support and cell recognition

Question 19

Which statement about the hydrophobic and hydrophilic regions of the plasma membrane is correct?

Accepted Answer

Hydrophobic regions are oriented toward the interior of the membrane, while hydrophilic regions face the aqueous environments.

Question 20

A cell is exposed to a toxin that disrupts the formation of peptide bonds. Which level of protein structure will be most directly affected?

Accepted Answer

Primary structure

Molecular Biology Foundations: DNA, RNA, Protein Structure, and the Eukaryotic Cell

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