Download Unit 2 Test Review

Biology
Dr. Cascio
Name ____________________
Date _______________
Unit 2 Test Review
1. What are the three subatomic
and their charges?
Proton +
neutron 0
6
C
12
carbon
electron -
particles
atomic
number? 6
Atomic mass? 12
# of protons? 6
# of neutrons? 6
# of electrons in neutral
atom? 6
2. What are the four organic compounds found in living things and what do they do?
Protein – movement, structure, immunity
Carbohydrates – quick energy, structure
Lipids – long-term storage of energy
Nucleic acids – genetics and ATP is for energy
3. Define the following:
solute__substance that is dissolved in a solvent to make a solution
solvent_substance in which a solute is dissolved to form a solution
monosaccharide__single sugar molecule
polysaccharide__large macromolecule formed from monosaccharides
amino acid__monomer of a protein________________
suspension__mixture of water and nondissolved materials
solution___mixture of two or more substances in which the molecules of the
substances are evenly distributed
activation energy__energy needed to get a reaction started
mass number___mass of the element = protons + neutrons
atomic number_ number of protons in an atom____________
Biology
Dr. Cascio
Name ____________________
Date _______________
**Look over the pH scale. Be familiar with both acids and bases.
4. What is a substance with a pH of 8 or above? __base___ What is a substance
with a pH of 6 or below?_acid___ What has a pH of 7?__pure water__
5. What charge is an ion when it gains an electron? _negative__
5.
How does a covalent bond form electrons are shared
6.
How does an ionic bond form? Electrons are transferred
7.
What do enzymes do? Decrease the activation energy needed to start a
reaction
8.
What is the activation site? Energy needed to start a reaction
9.
When hydrogen and oxygen combine to form water, what would the product(s)
be? __water_____ What would the reactant(s) be? __ hydrogen and oxygen __
8. List the chemical bonds (covalent, ionic, hydrogen bond) in order of decreasing
strength.
a. Covalent
b. ionic
c. hydrogen bond
9. What are the forces called that allow a gecko to climb up vertical surfaces?
__van der Waals____
10. What does the pH scale measure?___hydrogen ion__ concentration.
11. Where are protons and neutrons found in an atom? _nucleus_
12. In a glass of salt water, what is the solute? _salt__
What is the solvent? __water_____________
13. If an atom has an atomic number of 35 and a mass number of 75, how many
protons does it have?_35__ electrons?__35__ neutrons?__40_
Biology
Dr. Cascio
Name ____________________
Date _______________
16. Which molecule is the most abundant in the human body? water
17. Enzymes only work with specific substrates because each enzyme —

A. has a specific activation site for substrate attachment _
B. can only use a specific ionic bond with the enzyme
C. destroys its specific enzyme
D. actively interferes with other substrates around it
18. Enzymes decrease _activation__ energy and (increase )the rate of reaction.
** Know the macromolecule chart – monomers, polymers, examples, functions.
18. If a reaction absorbs energy in one direction, it will (release) energy going the
other direction.
19. What are the two types of intramolecular bonds (bonds that hold atoms together to
form molecules). Stronger bond: _covalent_ Weaker bond:__ionic__
20. What are the intermolecular forces (bonds that hold molecules together)?
_hydrogen bonbds__ and ___van der Waals_
21. Which is more acidic, a pH of 5.1, or a pH of 5.5? __5.1___
22. Which organic compound is the main source of energy for living organisms?
_carbohydrates_
23. What is the term for the energy needed to start a reaction? __activation_
_energy_
24. Chemical reactions that (release) energy may start by themselves.
25. Which is a stronger base, a pH of 11, or a pH of 1.0? pH 11
Biology
Dr. Cascio
Name ____________________
Date _______________
pH values of Some Common
Substances
Substance
pH
hydrochloric acid
1.0
tomatoes
4.0
rain water
6.2
distilled water
7.0
oven cleaner
11.1
Which is the strongest acid? Hydrochloric acid
sodium hydroxide
13.0
Ffd
Which substance is neutral? Distilled water