Question 1

Which of the following best describes a scientific theory in biology?

Accepted Answer

A broad explanation supported by a large body of evidence and able to generate new predictions.

Question 2

Which of the following is NOT a fundamental characteristic of life?

Accepted Answer

Ability to photosynthesize

Question 3

A carbon atom forms four covalent bonds in methane ($$CH_4). $$What property of carbon allows this?

Accepted Answer

Carbon has four electrons in its outer shell, allowing it to share electrons with four other atoms.

Question 4

Which of the following atoms makes up approximately 96% of the mass of a human?

Accepted Answer

Oxygen ($$O)$$

Question 5

If the $$pH of a $$solution changes from 6 to 4, how does the concentration of hydrogen ions ($$[H^+]) $$change?

Accepted Answer

It increases by 100 times.

Question 6

Which of the following best explains why water is a good solvent for polar molecules?

Accepted Answer

Water molecules form hydrogen bonds with polar molecules, allowing them to separate and dissolve.

Question 7

Which of the following is true about acids and bases?

Accepted Answer

Acids donate protons and bases accept protons.

Question 8

How many covalent bonds does carbon form in ethane ($$C_2H_6$$)?

Accepted Answer

7

Question 9

Which of the following best describes a hydrogen bond?

Accepted Answer

A weak attraction between a hydrogen atom covalently bonded to an electronegative atom and another electronegative atom.

Question 10

Which property of water allows insects to walk on its surface?

Accepted Answer

Cohesion due to hydrogen bonding

Question 11

Which of the following is a correct statement about the spontaneous generation hypothesis?

Accepted Answer

It states that living organisms arise from nonliving matter under certain conditions.

Question 12

Which of the following best describes the difference between covalent and ionic bonds?

Accepted Answer

Covalent bonds involve the sharing of electrons, while ionic bonds involve the transfer of electrons.

Question 13

Which of the following is the general term for molecules assembled from repeating units such as sugars, amino acids, and nucleotides?

Accepted Answer

Polymers

Question 14

Which of the following best explains why ice floats on water?

Accepted Answer

Hydrogen bonds in ice create a lattice structure that makes it less dense than liquid water.

Question 15

Which of the following is true about the atomic structure of sodium ($$Na$$)?

Accepted Answer

Sodium has 11 protons and 11 electrons in its neutral state.

Question 16

Which of the following is a correct prediction for the polarity of an organic molecule containing only carbon and hydrogen?

Accepted Answer

It will be nonpolar because carbon and hydrogen have similar electronegativities.

Question 17

Which of the following best describes the process of dehydration synthesis?

Accepted Answer

Joining monomers to form polymers by removing a water molecule.

Question 18

Which of the following is true about the $$pH$$ scale?

Accepted Answer

A solution with $$pH = 8 is $$more basic than a solution with $$pH = 2.$$

Question 19

Which of the following best explains why sodium chloride ($$NaCl) $$dissolves in water?

Accepted Answer

Water molecules surround and separate the $$Na^+$$ and $$Cl^-$$ ions due to their polarity.

Question 20

Which of the following is true about the number of covalent bonds in $$CO_2 ($$carbon dioxide)?

Accepted Answer

$$CO_2$$ has two double covalent bonds.

General Biology Study Guide: Life, Chemistry, Water, Acids & Bases, and Macromolecules

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