AP Biology: Biochemistry and Water Review

Front

What type of bond shares electrons?

Back

Covalent bond: A type of chemical bond where two atoms share one or more pairs of electrons.

Front

Water is an example of a _____________ substance.

Back

Polar substance: A molecule with a partial positive charge on one side and a partial negative charge on the other, leading to an uneven distribution of charge.

Front

The fact that ice floats on liquid water is due to the fact that water's solid form is _____________ than its liquid form.

Back

Less dense: Ice is less dense than liquid water, which is why it floats.

Front

What property allows moist air to retain its temperature better than dry air?

Back

High specific heat of water: Water can absorb a lot of heat before its temperature changes, due to its polarity and hydrogen bonding.

Front

Surface tension of water is the cohesive force between water molecules and other molecules. True or False?

Back

False: Surface tension is the cohesive force between water molecules themselves.

Front

Define hydrogen bond.

Back

Hydrogen bond: A weak bond between a hydrogen atom and an electronegative atom, often seen in water molecules.

Front

What is the significance of water's high specific heat?

Back

It helps regulate temperature in the environment and within organisms, allowing for stable conditions.

Front

Explain the term 'cohesion' in relation to water.

Back

Cohesion: The attraction between water molecules, which leads to phenomena like surface tension.

Front

What is the difference between polar and nonpolar molecules?

Back

Polar molecules have an uneven distribution of charge, while nonpolar molecules have an even distribution of charge.

Front

What is the role of water in biological systems?

Back

Water is essential for life; it acts as a solvent, regulates temperature, and participates in biochemical reactions.