Carboxyl group ($$\mathrm{\text{-COOH}})$$

Amino group ($$\mathrm{\text{-NH}_2})$$

Question 1

Which of the following best explains why carbon is able to form such a wide variety of molecules in living organisms?

Accepted Answer

Carbon has four valence electrons, allowing it to form up to four covalent bonds.

Question 2

A molecule with many C-H bonds is most likely to be:

Accepted Answer

Hydrophobic, because C-H bonds are nonpolar.

Question 3

Which functional group is most likely to act as an acid in biological molecules?

Accepted Answer

Carboxyl group ($$\mathrm{	ext{-COOH}})$$

Question 4

Which of the following is NOT a way that carbon skeletons can vary?

Accepted Answer

Type of functional group attached

Question 5

Which statement about isomers is correct?

Accepted Answer

Structural isomers have the same molecular formula but different connectivity of atoms.

Question 6

During the synthesis of a polymer, which type of reaction occurs and what is released?

Accepted Answer

Dehydration; water is released

Question 7

Which polysaccharide is used for energy storage in animals?

Accepted Answer

Glycogen

Question 8

What is the main structural difference between starch and cellulose?

Accepted Answer

Starch has $$\alpha-$$glucose linkages; cellulose has $$\beta-$$glucose linkages.

Question 9

Which level of protein structure is defined by the sequence of amino acids?

Accepted Answer

Primary structure

Question 10

Denaturation of a protein most directly affects which aspect of its structure?

Accepted Answer

Secondary, tertiary, and quaternary structures

Question 11

Which of the following correctly matches a nucleic acid with its sugar component?

Accepted Answer

DNA contains deoxyribose.

Question 12

Lipids are primarily composed of which two elements?

Accepted Answer

Carbon and hydrogen

Question 13

Phospholipids arrange themselves in a bilayer in cell membranes because:

Accepted Answer

Their phosphate heads are hydrophilic and face water, while fatty acid tails are hydrophobic and face inward.

Question 14

Which of the following is a function of steroids in biological systems?

Accepted Answer

Hormonal signaling

Question 15

Which of the following best describes the chemical structure of steroids?

Accepted Answer

Four fused carbon rings

Question 16

Which reaction is responsible for breaking down polymers into monomers?

Accepted Answer

Hydrolysis reaction

Question 17

Which of the following is a monomer of proteins?

Accepted Answer

Amino acid

Question 18

Which functional group is found in all amino acids and is responsible for their basic properties?

Accepted Answer

Amino group ($$\mathrm{	ext{-NH}_2})$$

Question 19

Which of the following best describes the difference between RNA and DNA bases?

Accepted Answer

RNA contains uracil; DNA contains thymine.

Question 20

A patient is unable to digest cellulose but can digest starch. Which of the following best explains this phenomenon?

Accepted Answer

Cellulose is made of $$\beta-$$glucose linkages, which human enzymes cannot break down.

Chapter 3: Carbon and the Molecular Diversity of Life – Study Notes

스터디 가이드 - 연습 문제