Biochemistry

Carbon is unique due to the carbon atom’s

• bonding properties

• six outer unpaired electrons

• ionic compounds

• hydrogen bonding strength

Which category of carbon-based molecules includes sugars and starches?

• unsaturated fatty acids

• phospholipids

• proteins

• carbohydrates

Fats, oils, and cholesterol are all type of

• cell membranes.

• hormones.

• lipids

• fatty acids.

Proteins are composed of which molecules?

• amino acids

• fatty acids

• monosaccharides

• nucleic acids

DNA and RNA are two types of

• proteins

• nucleic acids

• lipids

• carbohydrates

Which phrase best describes the effect of a catalyst on a chemical reaction?

• increases the temperature

• increases the volume of reactants

• decreases the reaction rate

• decreases the activation energy

Enzymes affect chemical reactions in living organisms by

• changing the direction of a reaction.

• breaking down molecules into starch.

• increasing the temperature range.

• weakening bonds in reactants.

The specific reactants that an enzyme acts on are called

• catalysts

• proteins

• substrates

• amino acids

Changes in temperature and pH can decrease an enzyme’s activity by breaking

• hydrogen bonds

• peptides

• amino acids

• sulfur-sulfur bonds

Which statement best describes the graph shown?

• More energy is released by the original reaction.

• Less energy is needed to start reaction B.

• The original reaction is catalyzed.

• Reaction B occurs at a slower rate.