Honors Biochemistry Test Review

 Proteins have many different functions in a cell. Which of the following are possible functions of a protein?

• catalysts and building blocks of DNA
• enzymes and actively transports molecules across the cell membrane
• building blocks of DNA and structural components of cell membrane
• components of the cell membrane and main source of energy in cellular respiration

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.

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

• carbohydrates
• lipids
• nucleic acids
• proteins

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

Tags

NGSS.HS-PS1-4

Which of the following best compares the structures of lipids and carbohydrates?  

• Both are made up of monosaccharide monomers, but lipids are hydrophobic and carbohydrates are hydrophilic.
• Both contain carbon and hydrogen, but carbohydrates also contain oxygen and lipids contain nitrogen.
• Both consist of carbon, hydrogen, and oxygen, but carbohydrates have repeating structural units and lipids do not.
• Both have a carbon backbone, but lipids also have an amino group and carbohydrates have a carboxylic acid group.

Some proteins catalyze biochemical reactions. If a genetic defect prevented a protein catalyst from being produced, which of the following do you predict would happen in the cell?

• The cell would find a different type of protein to catalyze the reaction
• The reaction the protein catalyzes would proceed very slowly or not at all
• The reaction the protein catalyzes would only occur in some places in the cell
• The reverse reaction of the one the protein catalyzes would begin to proceed

Which row in the chart below correctly pairs a food molecule with its building block?

• Row 1
• Row 2
• Row 3
• Row 4

Tags

NGSS.HS-LS1-6

A scientist analyzing an unknown substance has determined that it consists only of carbon, hydrogen and oxygen. During experimentation, she determines that the substance is soluble, or dissolves, in OIL but not in water. Which of the following macromolecules is the unknown substance most likely to be?

•  carbohydrate
• lipid
• nucleic acid
• protein

Living things use enzymes in the chemical reactions of metabolism. When food is digested, it is metabolized to release energy. Which statement best describes the role of an enzyme in this process?

• Because enzymes are proteins, they only react with other protein molecules, resulting in the production of glucose.
• The active site of the enzyme attached to the substrate of a food molecule produces carbon molecules, the building blocks of cells.
• The active site of an enzyme attached to a substrate prevents the chemical reactions involved in metabolism from happening too quickly.
• The active site of the enzyme binds to a substrate on a food molecule and the enzyme changes shape slightly, causing a chemical reaction to happen.

The table below lists some digestive enzymes found in the human small intestine. Based on the information in the table, what would be one effect of an injured pancreas?

• The blood levels of monosaccharides would increase.
• The absorption of amino acids would be more efficient.
• The body would be unable to process starches, proteins, and fats.
• The levels of the enzymes amylase, trypsin, and lipase would increase.