BIO 189 - Midterm Modules 1-3 Exam
Practice Guide 2026
1. Energy The capacity to do work
2. Reactant A chemical substance that is present at the start of a chemical reaction;
is written before the arrow
3. Product A substance produced in a chemical reaction; is written after the arrow
4. Cellular respiration Metabolic pathway where the bonds in macromolecules (ex: glucose)
are broken in order to create ATP.
5. Chemical bond The attractive force that holds atoms or ions together to form a
molecule
6. Macromolecules A very large organic molecule composed of many smaller molecules
, BIO 189 - Midterm Modules 1-3 Exam
Practice Guide 2026
7. Nutrients A substance that an organism must acquire from the environment to
support growth and survival.
8. Activation energy Energy needed to get a reaction started
9. Enzyme A type of protein that speeds up a chemical reactions by decreasing
the activation energy required to start the reaction
10. Substrate Specific molecule that can bind to the enzyme's active site and be
converted to a product. A reactant in an enzyme-mediated reaction.
11. Active site Part of an enzyme to which the substrate binds
, BIO 189 - Midterm Modules 1-3 Exam
Practice Guide 2026
12. Cofactor A nonprotein molecule or ion that is required for the proper function-
ing of an enzyme
Ex: Mg2+ ions
13. Coenzyme An organic cofactor that is required for the proper functioning of an
enzyme
Ex: NAD+
14. Phospholipid bilayer A double layer of phospholipids that makes up plasma and organelle
membranes
15. Plasma membrane
, BIO 189 - Midterm Modules 1-3 Exam
Practice Guide 2026
Another term for cell membrane
Regulates the types of molecules that can enter and exit the cell
16. Fluid mosaic model Model that describes how the cell membrane is composed of many
ditterent parts(such as lipids and proteins), and how these parts allow
the membrane to be flexible and fluid
17. Membrane protein A protein that is embedded within the phospholipid bilayer of the cell
membrane
18. Channel protein A type of membrane protein that allows specific solutes to cross the
cell membrane
Practice Guide 2026
1. Energy The capacity to do work
2. Reactant A chemical substance that is present at the start of a chemical reaction;
is written before the arrow
3. Product A substance produced in a chemical reaction; is written after the arrow
4. Cellular respiration Metabolic pathway where the bonds in macromolecules (ex: glucose)
are broken in order to create ATP.
5. Chemical bond The attractive force that holds atoms or ions together to form a
molecule
6. Macromolecules A very large organic molecule composed of many smaller molecules
, BIO 189 - Midterm Modules 1-3 Exam
Practice Guide 2026
7. Nutrients A substance that an organism must acquire from the environment to
support growth and survival.
8. Activation energy Energy needed to get a reaction started
9. Enzyme A type of protein that speeds up a chemical reactions by decreasing
the activation energy required to start the reaction
10. Substrate Specific molecule that can bind to the enzyme's active site and be
converted to a product. A reactant in an enzyme-mediated reaction.
11. Active site Part of an enzyme to which the substrate binds
, BIO 189 - Midterm Modules 1-3 Exam
Practice Guide 2026
12. Cofactor A nonprotein molecule or ion that is required for the proper function-
ing of an enzyme
Ex: Mg2+ ions
13. Coenzyme An organic cofactor that is required for the proper functioning of an
enzyme
Ex: NAD+
14. Phospholipid bilayer A double layer of phospholipids that makes up plasma and organelle
membranes
15. Plasma membrane
, BIO 189 - Midterm Modules 1-3 Exam
Practice Guide 2026
Another term for cell membrane
Regulates the types of molecules that can enter and exit the cell
16. Fluid mosaic model Model that describes how the cell membrane is composed of many
ditterent parts(such as lipids and proteins), and how these parts allow
the membrane to be flexible and fluid
17. Membrane protein A protein that is embedded within the phospholipid bilayer of the cell
membrane
18. Channel protein A type of membrane protein that allows specific solutes to cross the
cell membrane
