Question 1

Which of the following best describes the role of carbon in biological molecules?

Accepted Answer

Carbon serves as a skeleton for molecular shape, allowing functional groups to attach and confer chemical reactivity.

Question 2

Which statement about water's properties is most accurate in explaining its role as an efficient solvent in biological systems?

Accepted Answer

Water's ability to form hydrogen bonds with polar molecules enables it to dissolve a wide variety of substances.

Question 3

Amino acids are the monomers of which type of biological macromolecule, and what is the covalent bond that links them together?

Accepted Answer

Proteins; peptide bond $$\mathrm{(C-N)}$$

Question 4

Which of the following best explains why phospholipids form bilayers in water?

Accepted Answer

Phospholipids have both hydrophilic heads and hydrophobic tails, causing them to arrange with heads facing water and tails facing inward.

Question 5

Which of the following statements about DNA structure is correct?

Accepted Answer

DNA strands are antiparallel, meaning one strand runs 5' to 3' and the other runs 3' to 5'.

Question 6

Which of the following is a function of proteins in cells?

Accepted Answer

Proteins catalyze chemical reactions as enzymes.

Question 7

Which property of water is most responsible for its ability to moderate temperature in living organisms?

Accepted Answer

Water's high specific heat capacity, which allows it to absorb and release large amounts of heat with little temperature change.

Question 8

Which of the following best describes a spontaneous chemical reaction?

Accepted Answer

A reaction that increases the entropy of the system and has a negative change in free energy $$\Delta G \u003c 0.$$

Question 9

Which of the following statements about diffusion across a membrane is correct?

Accepted Answer

Diffusion is the movement of molecules from areas of high concentration to low concentration down a concentration gradient.

Question 10

Which of the following is true about the structure and function of monosaccharides?

Accepted Answer

Monosaccharides differ from one another by the arrangement of atoms and the number of carbon atoms.

Question 11

Which of the following best explains the difference between saturated and unsaturated fatty acids?

Accepted Answer

Saturated fatty acids have no double bonds between carbon atoms, making them solid at room temperature; unsaturated fatty acids have one or more double bonds, making them liquid at room temperature.

Question 12

Which of the following is a correct statement about the directionality of DNA strands?

Accepted Answer

DNA strands are antiparallel, with one running 5' to 3' and the other 3' to 5'.

Question 13

Which of the following is NOT a function of carbohydrates in cells?

Accepted Answer

Carbohydrates act as enzymes to catalyze chemical reactions.

Question 14

Which of the following best describes the process of osmosis?

Accepted Answer

Osmosis is the diffusion of water molecules across a selectively permeable membrane from an area of low solute concentration to high solute concentration.

Question 15

Which of the following statements about the plasma membrane is correct?

Accepted Answer

The plasma membrane controls the movement of substances into and out of the cell.

Question 16

Which of the following is true about the polymerization of nucleotides to form nucleic acids?

Accepted Answer

Polymerization of nucleotides requires energy, which is provided by the hydrolysis of nucleotide triphosphates.

Question 17

Which of the following best describes the function of RNA in cells?

Accepted Answer

RNA allows DNA to be used as a template to transcribe RNA and can be used as a template to synthesize proteins.

Question 18

Which of the following is a correct statement about the acid-base properties of water?

Accepted Answer

Water can ionize to form $$\mathrm{H^+}$$ and $$\mathrm{OH^-}$$ ions.

Question 19

Which of the following is true about the relationship between structure and function in proteins?

Accepted Answer

The primary structure of a protein determines its final folded shape and function.

General Biology Unit 1: Foundations of Life, Chemistry, and Cell Structure

Guida di studio - Domande di pratica

Study guide - Flashcard