Biology Sol Review Biochemistry

In living cells, enzymes act as catalysts, which may reduce the amount of activation energy required for a chemical reaction to occur. In the graphs below, pathway x is a solid line representing the uncatalyzed reaction. The dotted line shows the catalyzed reaction. Which graph best illustrates the changes in a reaction when the catalyst reduces the amount of energy required?

• A

• B

• C

• D

Answer explanation

Both lines begin at the same level but the catalyzed reaction shows a decrease in the activation energy...

Tags

NGSS.HS-PS1-4

The diagram shows the general structure of an amino acid. Which type of molecule is formed from amino acids?

• lipids

• proteins

• carbohydrates

• nucleic acids

Answer explanation

Amino Acids are the MONOMERS for building Proteins...

Tags

NGSS.HS-LS1-1

What will most likely happen if an appropriate enzyme is added to a chemical reaction?

• The reaction rate will increase.

• The equilibrium of the reaction will be maintained. 

• The reaction rate will decrease.

• The reaction will stop.

Answer explanation

Enzymes speed up reactions by decreasing the activation energy...

Tags

NGSS.HS-PS1-5

A sugar, a phosphate group, and a nitrogen base form the building blocks of which organic compound?

• carbohydrates

• lipids

• nucleic acids

• proteins

A steroid is an example of a ​ (a)  

• Iipid

• protein

• carbohydrate

• nucleic acid

A steroid is an example of ​a (a)  

• lipid

• protein

• nucleic acid

• carbohydrate

The human body maintains a temperature of around 98.6 degrees at all times. Enzymes are involved in almost every chemical reaction in the body. Which of the following describes the connection between these two statements?

• Enzymes function best at a specific temperature.

• The body needs to be warm to prevent hypothermia.

• The body is kept relatively warm to prevent too much enzyme action.

• There is no connection between the two statements.

Answer explanation

Extreme pH and temperature changes denature proteins damaging the active site of enzymes...

Tags

NGSS.HS-LS1-3

The enzyme lactase will break down the sugar lactose into which of the following components?

• monosaccharides

• nucleic acids

• amino acids

• phospholipids

Answer explanation

Lactose is a Disaccharide (two molecules of glucose bonded), the enzyme lactase breaks the lactose into two individual monosaccharides...

As food travels through the digestive system, it is exposed to a variety of pH levels. The stomach has a pH of 2 due to the presence of hydrochloride acid (HCl), and the small intestine has a pH ranging from 7 to 9. HCl converts pepsinogen into pepsin, an enzyme that digests proteins in the stomach. Which of the following most likely happens to pepsin as it enters the small intestine?

• It becomes inactive.

• It begins to replicate.

• It's shape changes to engulf large proteins.

• It's activity increases to digest more proteins.

Answer explanation

Extremes changes of pH denatures the enzymes...

Fats, oils and cholesterol are all types of what?

• cell membranes

• hormones

• lipids

• fatty acids