EXAM 2 BIO 1201 UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS
VERIFIED 2027 EDITION
1. What is passive transport?
- no energy used - moves molecules from high to low concentration (e.g., diffusion, osmosis)
2. What is an active transport?
- requires energy (ATP) - moves molecules from low to high concentration
3. What is bulk transport?
- moves large molecules or lots of molecules at once - requires energy (ATP) - Endocytosis (into cell) -
Exocytosis (out of the cell)
4. What does amphipathic mean, and how do phospholipids represent this concept?
Amphipathic means something has a water-loving part and a water-fearing part. Phospholipids show this
because they have a head that likes water (face water) and tails that hate water (avoid water) and this
helps them form the cell membrane's structure.
5. What is the fluid mosaic model?
the cell membrane is soft and flexible, made of fat molecules with proteins mixed in, like a moving puzzle
6. how do saturated and unsaturated fatty acids work with temperature?
- Saturated fats: straight tails, pack tightly --> less fluid (especially in cold) - Unsaturated fats: bent tails,
don't pack well --> more fluid (help in cold) - at low temps, unsaturated fats keep the membrane from
getting too stiff - at high temps, saturated fats help prevent the membrane from becoming too loose
7. What are types of membrane proteins and what are their properties?
Types of Membrane Proteins: - Integral proteins- inside membrane, help transport and signaling -
Peripheral proteins- on membrane surface; help support and signaling - Lipid-anchored proteins- attached
to lipids, involved in signaling Properties: - Amphipathic - Selective - Dynamic
8. What is the role of carbohydrates in the membrane?
carbohydrates help cells recognize each other, protect the cell, and help cells stick together
9. what can, and cannot, permeate the membrane and why?
Can permeate (pass): - small, nonpolar molecules (oxygen, carbon dioxide) - small polar molecules (water,
but slowly) Cannot permeate (pass): - large molecules - charged ions (Na+, Cl-) Why: - membrane's
hydrophobic core blocks big and charged substances
10. How do different transport proteins work?
Transport proteins help move substances across the membrane: - channel proteins- form pores for fast
movement (like a tunnel) - carrier proteins- bind and carry molecules across slowly (like a door) - pump
proteins- use energy (ATP) to move substances against the gradient (low --> high concentration)
11. How does osmosis work?
osmosis is water moving through a membrane from and aera with more water to where there's less water.
12. what does hypotonic mean?
more water outside --> water moves in - human cells: may bust (lyse) - plant cells: swell and become firm
(turgid)
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, 13. what does hypertonic mean?
less water outside --> water moves out - human cells: shrink (crenate) - plant cells: shrink, membrane pulls
away (plasmolysis)
14. what does isotonic mean?
equal water --> no net movement - human cells: stay normal - plant cells: they are floppy (flaccid)
15. how does the sodium-potassium pump work?
(eukaryotes) - uses ATP - pumps 3 Na+ out and 2 K+ in - maintains charge and ion balance in cells - move
ions against their concentration gradient using energy
16. how does the proton pump work?
(all domains of life) - uses ATP - pumps H+ (protons) out of the cell - creates a proton gradient used for
energy (like making ATP) - move ions against their concentration gradient using energy
17. what is membrane potential, and how does it affect the membrane?
membrane potential is the electric charge difference across the cell membrane - inside = more negative -
outside = more positive it affects the membrane by helping: - move ions in/out - send signals (like nerve
impulses) - power transport proteins (like pumps)
18. what is endocytosis?
- cell takes in large materials - phagocytosis: "cell eating" (solids) - pinocytosis: "cell drinking" (fluids) -
receptor-mediated: takes in specific molecules using receptors - use energy (ATP) and move big stuff
across the membrane
19. what is exocytosis?
- cell releases large materials - vesicles fuse with membrane to push stuff out - uses energy (ATP) and
move big stuff across the membrane
20. what is the basic premise of metabolic pathways?
metabolic pathways are step-by-step chemical reactions in a cell that build or break down molecules. -
catabolic: break molecules --> release energy - anabolic: build molecules --> use energy each step is helped
by a specific enzyme
21. what is anabolic?
- builds molecules - uses energy (ATP) - example: making proteins
22. what is catabloic?
- breaks down molecules - releases energy - example: breaking down glucose (cellular respiration)
23. what are the different forms of energy, and how are they involved in metabolism?
Kinetic energy- energy of motion (molecules moving) Potential energy- stored energy (in chemical bonds)
Chemical energy- a type of potential energy in molecules (like glucose or ATP) In metabolism: - catabolic
pathways release chemical energy - anabolic pathways use chemical energy (usually from ATP)
24. what are the different types of systems, and what type of system is metabolism?
Open system- exchange energy and matter with surroundings Closed system- exchange energy, not
matter Isolated system- no exchange of energy or matter Metabolism is an open system - it takes in
energy and matter (like food) and releases waste and heat
25. what are the laws of thermodynamics?
First law- energy can't be created or destroyed, only changed (energy is conserved) Second law- every
energy transfer increases entropy (disorder); some energy is lost as heat
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VERIFIED 2027 EDITION
1. What is passive transport?
- no energy used - moves molecules from high to low concentration (e.g., diffusion, osmosis)
2. What is an active transport?
- requires energy (ATP) - moves molecules from low to high concentration
3. What is bulk transport?
- moves large molecules or lots of molecules at once - requires energy (ATP) - Endocytosis (into cell) -
Exocytosis (out of the cell)
4. What does amphipathic mean, and how do phospholipids represent this concept?
Amphipathic means something has a water-loving part and a water-fearing part. Phospholipids show this
because they have a head that likes water (face water) and tails that hate water (avoid water) and this
helps them form the cell membrane's structure.
5. What is the fluid mosaic model?
the cell membrane is soft and flexible, made of fat molecules with proteins mixed in, like a moving puzzle
6. how do saturated and unsaturated fatty acids work with temperature?
- Saturated fats: straight tails, pack tightly --> less fluid (especially in cold) - Unsaturated fats: bent tails,
don't pack well --> more fluid (help in cold) - at low temps, unsaturated fats keep the membrane from
getting too stiff - at high temps, saturated fats help prevent the membrane from becoming too loose
7. What are types of membrane proteins and what are their properties?
Types of Membrane Proteins: - Integral proteins- inside membrane, help transport and signaling -
Peripheral proteins- on membrane surface; help support and signaling - Lipid-anchored proteins- attached
to lipids, involved in signaling Properties: - Amphipathic - Selective - Dynamic
8. What is the role of carbohydrates in the membrane?
carbohydrates help cells recognize each other, protect the cell, and help cells stick together
9. what can, and cannot, permeate the membrane and why?
Can permeate (pass): - small, nonpolar molecules (oxygen, carbon dioxide) - small polar molecules (water,
but slowly) Cannot permeate (pass): - large molecules - charged ions (Na+, Cl-) Why: - membrane's
hydrophobic core blocks big and charged substances
10. How do different transport proteins work?
Transport proteins help move substances across the membrane: - channel proteins- form pores for fast
movement (like a tunnel) - carrier proteins- bind and carry molecules across slowly (like a door) - pump
proteins- use energy (ATP) to move substances against the gradient (low --> high concentration)
11. How does osmosis work?
osmosis is water moving through a membrane from and aera with more water to where there's less water.
12. what does hypotonic mean?
more water outside --> water moves in - human cells: may bust (lyse) - plant cells: swell and become firm
(turgid)
1
, 13. what does hypertonic mean?
less water outside --> water moves out - human cells: shrink (crenate) - plant cells: shrink, membrane pulls
away (plasmolysis)
14. what does isotonic mean?
equal water --> no net movement - human cells: stay normal - plant cells: they are floppy (flaccid)
15. how does the sodium-potassium pump work?
(eukaryotes) - uses ATP - pumps 3 Na+ out and 2 K+ in - maintains charge and ion balance in cells - move
ions against their concentration gradient using energy
16. how does the proton pump work?
(all domains of life) - uses ATP - pumps H+ (protons) out of the cell - creates a proton gradient used for
energy (like making ATP) - move ions against their concentration gradient using energy
17. what is membrane potential, and how does it affect the membrane?
membrane potential is the electric charge difference across the cell membrane - inside = more negative -
outside = more positive it affects the membrane by helping: - move ions in/out - send signals (like nerve
impulses) - power transport proteins (like pumps)
18. what is endocytosis?
- cell takes in large materials - phagocytosis: "cell eating" (solids) - pinocytosis: "cell drinking" (fluids) -
receptor-mediated: takes in specific molecules using receptors - use energy (ATP) and move big stuff
across the membrane
19. what is exocytosis?
- cell releases large materials - vesicles fuse with membrane to push stuff out - uses energy (ATP) and
move big stuff across the membrane
20. what is the basic premise of metabolic pathways?
metabolic pathways are step-by-step chemical reactions in a cell that build or break down molecules. -
catabolic: break molecules --> release energy - anabolic: build molecules --> use energy each step is helped
by a specific enzyme
21. what is anabolic?
- builds molecules - uses energy (ATP) - example: making proteins
22. what is catabloic?
- breaks down molecules - releases energy - example: breaking down glucose (cellular respiration)
23. what are the different forms of energy, and how are they involved in metabolism?
Kinetic energy- energy of motion (molecules moving) Potential energy- stored energy (in chemical bonds)
Chemical energy- a type of potential energy in molecules (like glucose or ATP) In metabolism: - catabolic
pathways release chemical energy - anabolic pathways use chemical energy (usually from ATP)
24. what are the different types of systems, and what type of system is metabolism?
Open system- exchange energy and matter with surroundings Closed system- exchange energy, not
matter Isolated system- no exchange of energy or matter Metabolism is an open system - it takes in
energy and matter (like food) and releases waste and heat
25. what are the laws of thermodynamics?
First law- energy can't be created or destroyed, only changed (energy is conserved) Second law- every
energy transfer increases entropy (disorder); some energy is lost as heat
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