Unit Test — Unit test Answers

0 verified answers
1
Free Preview

Which statement describes how enzymes and substrates are related?

A
The enzyme influences the speed of change from substrate to product.
B
Enzymes are released as substrates in a chemical reaction.
C
An enzyme is a special kind of substrate in a chemical reaction.
D
Substrates combine with enzymes to form reactants.
2
Free Preview

What would happen to life on Earth if all the liquid fresh water were used up?

A
All organisms would adapt to using salt water.
B
Organisms would carry out life functions without water.
C
Animals would be affected, but some desert plants would survive.
D
Life could no longer exist on Earth.
3

The diagram shows two water molecules. What does the dotted line between the water molecules represent?

Question illustration
A
a polar bond
B
a covalent bond
C
a hydrogen bond
D
an electronegative bond
4

Sublimation is the opposite of deposition just as evaporation is the opposite of

A
fusion
B
transpiration
C
freezing
D
condensation
5

A dietician examines the diet of a patient who is complaining that he is unable to build muscle mass. The patient eats mainly fresh fruits, vegetables, pasta, bread, and some fats and oils. Which type of supplement will the dietician most likely recommend?

A
citric acid
B
fatty acids
C
nucleic acids
D
amino acids
6

By which process do plants obtain carbon from the atmosphere?

A
photosynthesis
B
cellular respiration
C
decomposition
D
consumption
7

Which shows the most direct path that carbon can take through the carbon cycle?

A
plant ® atmosphere ® animal
B
animal ® plant ® atmosphere
C
plant ® animal ® atmosphere
D
atmosphere ® animal ® fossil fuel
8

How does a catalyst influence a chemical reaction?

A
It speeds up or slows down a chemical reaction by direct participation.
B
It reacts with products to increase the concentration of reactants.
C
It decreases the amount of energy necessary for the reaction to proceed.
D
It increases the total amount of products formed.
9

Which component is affected when a catalyst is added to a chemical reaction?

A
the amount of substrate
B
the activation energy
C
the amount of product
D
the concentration of reactants
10

By which process does water vapor become a cloud?

A
evaporation
B
transpiration
C
condensation
D
precipitation
11

Which reaction is exothermic?

A
a reaction that absorbs energy from the environment
B
a reaction that requires an activation energy
C
a reaction that releases energy into the environment
D
a reaction that does not involve a change in energy
12

Which macromolecule is the main source of energy for living things?

A
fat
B
nucleic acid
C
protein
D
carbohydrate
13

Which statement describes one way that RNA differs from DNA?

A
One is a protein, and the other is a nucleic acid.
B
They contain different five-carbon sugars and a different nitrogenous base.
C
They are both carbohydrates, but one is a polysaccharide.
D
One provides energy, and the other carries genetic information.
14

Which process is performed by both plants and animals to break down sugars to provide energy in the form of ATP?

A
photosynthesis
B
cellular respiration
C
consumption
D
decomposition
15

Which type of macromolecule is made up of subunits that are called amino acids?

A
carbohydrate
B
lipid
C
nucleic acid
D
protein

Did you find these answers helpful?