Question 1

Which of the following is NOT one of the five fundamental characteristics of all living things?

Accepted Answer

They are capable of photosynthesis.

Question 2

A neutral atom of carbon-14 ($$^{14}C) $$has how many protons, neutrons, and electrons?

Accepted Answer

6 protons, 8 neutrons, 6 electrons

Question 3

Which statement best explains why water molecules are able to form hydrogen bonds with each other?

Accepted Answer

Water molecules have partial positive and negative charges due to polar covalent bonds.

Question 4

Which of the following best describes an ionic bond?

Accepted Answer

A bond formed by the transfer of electrons from one atom to another, resulting in oppositely charged ions.

Question 5

Which element is NOT one of the four most abundant elements in living organisms?

Accepted Answer

Calcium

Question 6

A molecule of methane ($$CH_4) is $$held together by which type of bond?

Accepted Answer

Nonpolar covalent bonds

Question 7

Which of the following best explains why sodium (Na) and chlorine (Cl) form an ionic bond in table salt ($$NaCl$$)?

Accepted Answer

Sodium donates an electron to chlorine, resulting in oppositely charged ions that attract each other.

Question 8

Which of the following statements about isotopes is TRUE?

Accepted Answer

Isotopes of an element have different numbers of neutrons.

Question 9

Which of the following best describes the relationship between atomic structure and chemical reactivity?

Accepted Answer

Atoms with incomplete valence shells tend to form bonds to achieve stability.

Question 10

Which of the following is a real-world example of a hydrogen bond's importance in biology?

Accepted Answer

The double-helix structure of DNA being stabilized by bonds between complementary bases.

Question 11

Which of the following best explains why oxygen is more electronegative than hydrogen?

Accepted Answer

Oxygen has more protons, increasing its pull on electrons.

Question 12

A student mixes sugar into water and observes that the sugar dissolves. Which property of water is most responsible for this phenomenon?

Accepted Answer

Water's ability to form hydrogen bonds with polar molecules

Question 13

Which of the following best describes a polar covalent bond?

Accepted Answer

Electrons are shared unequally, resulting in partial charges on the atoms.

Question 14

Which of the following is the correct order of biological organization from largest to smallest?

Accepted Answer

Organisms → Cells → Molecules → Atoms

Question 15

A patient is exposed to a radioactive isotope of iodine for medical imaging. Which property of isotopes makes this possible?

Accepted Answer

Isotopes have unstable nuclei that can emit radiation.

Question 16

Which of the following best explains why carbon is so important in the chemistry of life?

Accepted Answer

Carbon can form up to four covalent bonds, allowing for complex molecules.

Question 17

If an atom has an atomic number of 8 and a mass number of 18, how many neutrons does it have?

Accepted Answer

10

Question 18

Which of the following best describes the difference between a cation and an anion?

Accepted Answer

A cation has lost electrons and is positively charged; an anion has gained electrons and is negatively charged.

Question 19

Which of the following scenarios best illustrates the concept that 'structure affects function' in biology?

Accepted Answer

The double-helix structure of DNA allows it to store genetic information efficiently.

Question 20

Which of the following best explains why noble gases are chemically inert?

Accepted Answer

They have full valence shells, making them stable and unlikely to form bonds.

Chapter 2: Chemical Basis of Life – General Biology Study Notes

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