PSL 250 - FINAL EXAM (MODULES 1-5 LEARNING
OBJECTIVES UPDATED ACTUAL QUESTIONS AND
CORRECT ANSWERS
Question:
1. 1. (Lecture #2) - Define homeostasis and the components of a homeostatic system.
Answer:
Homeostasis - The ability of an organism to maintain consistent internal environment, or "steady state," in
response to changing internal or external conditions.
- hundreds of anatomic structures and physiologic processes are continuously monitored and adjusted
components:
1. stimulus - changes in a variable that is regulates (temperature, stretch in muscle)
2. receptor - structure that detects the stimulus (sensory neurons, stretch receptors)
3. receptor sends input information to the control center (if receptor and control center are separate
structures)
4. control center - integrates input and initiates change through the effectors (usually brain or endocrine
gland)
5. control center sends output information to an effector (initiates response)
6. effector - structure that brings about a change to the stimulus (muscle or gland)
7. homeostasis restored
Question:
2. 2. (Lecture #2) - List the four organic biological macromolecules and atoms that make up these
macromolecules.
Answer:
carbohydrates proteins lipids nucleic acids
- biological macromolecules always contain carbon, hydrogen, and generally oxygen atoms
- some also contain: phosphorus, nitrogen, and sulfur
- CHON PS - Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur
Question:
3. 3. (Lecture #3) - Distinguish between cellular processes of passive membrane transport including simple
diffusion and facilitated diffusion.
Answer:
passive processes - no expenditure of cellular energy required; substances move down their concentration
gradient diffusion - movement of solutes osmosis - movement of water across a selectively permeable
membrane simple diffusion - no transport protein required facilitated diffusion - transport protein required
channel-mediated - ion moves through channel carrier-mediated - small polar molecule moved by carrier
protein
diffusion - factors that influence the rate of diffusion:
1. temperature (increased temp = faster rate of diffusion)
2. concentration gradient (larger gradient = faster rate of diffusion)
3. distance (larger distance = slower rate of diffusion)
4. surface area (larger surface area = faster rate of diffusion)
5. size of the particle (larger particles = slower rate of diffusion)
- system always moves towards equilibrium
, Question:
4. 4. Lecture #4B) - Explain the process of osmosis.
Answer:
osmosis - the passive movement of water through a selectively permeable (or semipermeable) membrane
down its concentration gradient
- water can slip between phospholipids via "water channels" aka aquaporins in the plasma membrane
- aquaporins are integral membrane proteins that span the entire membrane
- "water follows solute" so it will always follow the concentration gradient
Question:
5. 5. (Lecture #4B) - Describe the effect an isotonic, hypotonic, and hypertonic solution will have on a cell.
Answer:
tonicity - the ability of a solution to change the volume or pressure of a cell by osmosis
isotonic: iso = same, solute concentration of the solution is the same, no net movement hypotonic: hypo =
under, solute concentration of the solution is lower outside of the cell, water moves into the cell
hypertonic: hyper = more than, solute concentration of the solution is higher outside of the cell, water
moves out of the cell
if a cell is placed in a... isotonic solution - cell shape is normal (biconcave) hypotonic solution - cell will
burst (hemolysis) hypertonic solution - cell will shrivel (crenate)
Question:
6. 6. (Lecture #5) - Name the different layers of the integumentary system and the different tissues in those
layers.
Answer:
1. epidermis - stratified squamous epithelium
2. dermis - deeper layer, dense irregular connective tissue (attaches hypodermis with epidermis)
3. subcutaneous layer (hypodermis) - areolar and adipose connective tissue (not part of integumentary
system)
Question:
7. 7. (Lecture #5) - Differentiate between thick and thin skin.
Answer:
thick skin:
- palms of hands, soles of feet
- has all five layers of epidermis
- houses sweat glands
- no hair follicles or sebaceous glands
- from 0.4-0.6 mm thick
- has more stratum corneum
thin skin:
- most of body (95%)
- sweat glands
- hair follicles
- sebaceous glands
- from 0.075-0.15 mm thick
- has less stratum corneum
OBJECTIVES UPDATED ACTUAL QUESTIONS AND
CORRECT ANSWERS
Question:
1. 1. (Lecture #2) - Define homeostasis and the components of a homeostatic system.
Answer:
Homeostasis - The ability of an organism to maintain consistent internal environment, or "steady state," in
response to changing internal or external conditions.
- hundreds of anatomic structures and physiologic processes are continuously monitored and adjusted
components:
1. stimulus - changes in a variable that is regulates (temperature, stretch in muscle)
2. receptor - structure that detects the stimulus (sensory neurons, stretch receptors)
3. receptor sends input information to the control center (if receptor and control center are separate
structures)
4. control center - integrates input and initiates change through the effectors (usually brain or endocrine
gland)
5. control center sends output information to an effector (initiates response)
6. effector - structure that brings about a change to the stimulus (muscle or gland)
7. homeostasis restored
Question:
2. 2. (Lecture #2) - List the four organic biological macromolecules and atoms that make up these
macromolecules.
Answer:
carbohydrates proteins lipids nucleic acids
- biological macromolecules always contain carbon, hydrogen, and generally oxygen atoms
- some also contain: phosphorus, nitrogen, and sulfur
- CHON PS - Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur
Question:
3. 3. (Lecture #3) - Distinguish between cellular processes of passive membrane transport including simple
diffusion and facilitated diffusion.
Answer:
passive processes - no expenditure of cellular energy required; substances move down their concentration
gradient diffusion - movement of solutes osmosis - movement of water across a selectively permeable
membrane simple diffusion - no transport protein required facilitated diffusion - transport protein required
channel-mediated - ion moves through channel carrier-mediated - small polar molecule moved by carrier
protein
diffusion - factors that influence the rate of diffusion:
1. temperature (increased temp = faster rate of diffusion)
2. concentration gradient (larger gradient = faster rate of diffusion)
3. distance (larger distance = slower rate of diffusion)
4. surface area (larger surface area = faster rate of diffusion)
5. size of the particle (larger particles = slower rate of diffusion)
- system always moves towards equilibrium
, Question:
4. 4. Lecture #4B) - Explain the process of osmosis.
Answer:
osmosis - the passive movement of water through a selectively permeable (or semipermeable) membrane
down its concentration gradient
- water can slip between phospholipids via "water channels" aka aquaporins in the plasma membrane
- aquaporins are integral membrane proteins that span the entire membrane
- "water follows solute" so it will always follow the concentration gradient
Question:
5. 5. (Lecture #4B) - Describe the effect an isotonic, hypotonic, and hypertonic solution will have on a cell.
Answer:
tonicity - the ability of a solution to change the volume or pressure of a cell by osmosis
isotonic: iso = same, solute concentration of the solution is the same, no net movement hypotonic: hypo =
under, solute concentration of the solution is lower outside of the cell, water moves into the cell
hypertonic: hyper = more than, solute concentration of the solution is higher outside of the cell, water
moves out of the cell
if a cell is placed in a... isotonic solution - cell shape is normal (biconcave) hypotonic solution - cell will
burst (hemolysis) hypertonic solution - cell will shrivel (crenate)
Question:
6. 6. (Lecture #5) - Name the different layers of the integumentary system and the different tissues in those
layers.
Answer:
1. epidermis - stratified squamous epithelium
2. dermis - deeper layer, dense irregular connective tissue (attaches hypodermis with epidermis)
3. subcutaneous layer (hypodermis) - areolar and adipose connective tissue (not part of integumentary
system)
Question:
7. 7. (Lecture #5) - Differentiate between thick and thin skin.
Answer:
thick skin:
- palms of hands, soles of feet
- has all five layers of epidermis
- houses sweat glands
- no hair follicles or sebaceous glands
- from 0.4-0.6 mm thick
- has more stratum corneum
thin skin:
- most of body (95%)
- sweat glands
- hair follicles
- sebaceous glands
- from 0.075-0.15 mm thick
- has less stratum corneum
