Question

biol 105 exam 2

1. a protein that speeds up the rate of a chemical reaction is called a(an):

a. enzyme.
b. amino acids.
c. fatty acids.
d. nucleic acids.

1. anabolic reactions __ bonds, whereas catabolic reactions __ bonds.

a. loosen; tighten
b. make; break
c. decrease; increase
d. break; make

1. all the chemical reactions that occur in your body are collectively called:

a. nutrients.
b. catabolism.
c. anabolism.
d. metabolism.

1. enzymes work by:

a. modifying carbohydrates.
b. lowering activation energy.
c. lowering cell energy.
d. raising cell temperature.

1. when humans exercise, they burn up energy that was stored in their muscles as complex carbohydrates in the form of:

a. glycogen.
b. simple sugars.
c. starch.
d. fats.

1. can a cheeseburger be used to make all of the macromolecules needed for a cell?

a. no, a cheeseburger is missing the fats needed to make a cell membrane.
b. no, a cheeseburger is missing carbohydrates, which are needed to make a cell.
c. no, a cheeseburger does not have all the different types of subunits required to make a cell.
d. yes, a cheeseburger has protein, carbohydrates, and fats, which can be broken down into their subunits and reassembled into cellular structures.

1. a major difference between algae as a renewable oil source and current nonrenewable sourcing of oil is:

a. current oil reserves are largely inaccessible and thus not practical.
b. current oil reserves take millions of years to form deep in earth and cannot meet long - term demand.
c. although algae are renewable, they do not produce enough oil to be useful.
d. algae take millions of years to form enough oil to meet the needs of humans.

Explanation:

1. Enzymes are proteins that catalyze (speed - up) chemical reactions.
2. Anabolic reactions build molecules by making bonds, while catabolic reactions break down molecules by breaking bonds.
3. Metabolism is the sum of all chemical reactions in the body.
4. Enzymes lower the activation energy required for a chemical reaction to occur.
5. Glycogen is the storage form of glucose in muscles and liver, and it is burned during exercise for energy.
6. A cheeseburger has protein, carbohydrates, and fats which can be broken down and reassembled into cellular structures.
7. Current non - renewable oil reserves take millions of years to form deep in the Earth.

Answer:

1. a. enzyme
2. b. make; break
3. d. metabolism
4. b. lowering activation energy
5. a. glycogen
6. d. Yes, a cheeseburger has protein, carbohydrates, and fats, which can be broken down into their subunits and reassembled into cellular structures.
7. b. current oil reserves take millions of years to form deep in Earth and cannot meet long - term demand.