PHGY 215 Exam Questions and Answers Already Passed Latest Update 2025-2026
What is a SET POINT? - Answers -the range/point that a variable physiological state stabilizes
(normal range)
What are 3 components of the HOMEOSTATIC CONTROL SYSTEM? - Answers sensor
integrator
effector
What does an SENSOR do? - Answers detects environmental variable change
What does an INTEGRATOR do? - Answers compares variable to set point
What does an EFFECTOR do? - Answers restores variable to set point
What is INTRINSIC regulation? - Answers S, I, E all within a tissue
ex: exercising skeletal muscle
What is EXTRINSIC regulation? - Answers S,I, E all outside of effected tissue
ex: most homeostatic control systems
What is NEGATIVE FEEDBACK? - Answers once set point is restored, system stops/reverses
signalling to halt action
ex: most homeostatic control systems
What is POSITIVE FEEDBACK? - Answers amplifies signalling output to increase desired
outcome (not homeostatic)
What are the 6 components of the CELL MEMBRANE - Answers 1. plasma membrane
2. phospholipid bilayer
3. cholesterol
4. membrane proteins
5. ion channels
,6. carb chains
What is the function of the PLASMA MEMBRANE? - Answers -barrier that separates cells
internal from external environment
What are the 3 primary functions of the PLASMA MEMBRANE? - Answers 1. ensure cells survive
2. maintain homeostasis
3. communicate w surrounding cells
TRUE OR FALSE: phospholipids have non-polar heads and polar tails - Answers FALSE
*polar head, NP tails
TRUE OR FALSE: phospholipids have hydrophillic heads and hydrophobic tails - Answers true
What is the function CHOLESTEROL in the cell membrane? - Answers -prevents carb chains
from packing to tightly
-maintains membrane fluid
-located between phospholipids
What is the function MEMBRANE PROTEINS in the cell membrane? - Answers -cell
structure/function
-cell signalling
-transport
What is the function ION CHANNELS in the cell membrane? - Answers -specialized channels
that permit entry/exit of ions
What is the function CARB CHAINS in the cell membrane? - Answers -cell receptors
-stabilize membrane
, -transport
What is the FLUID MOSAIC MODEL? - Answers -describes cell membrane structure as a flexible,
dynamic bilayer of phospholipids with embedded proteins that move laterally. The "fluid" part
refers to the mobility of lipids and proteins within the membrane, while the "mosaic" represents
the diverse proteins scattered throughout. Components like cholesterol and carbohydrates also
contribute to membrane stability and function. This model highlights the membrane's role in
regulating the movement of substances and facilitating cell communication.
What are 3 types of CELLULAR ADHESIONS? - Answers -extracellular matrix (ECM)
-cell adhesion molecules (CAMs)
-cell junctions
What are the 3 components of the ECM? - Answers -interstitial fluid surrounding all cells
composed of: COLLGEN (tensile), ELASTIN (stretch/recoil), and FIBRONECTIN (promotes
adhesion)
What are CAMs? - Answers -transmembrane proteins who's intracellular side composes the
cytoskeleton and extracellular side faces the ECM
What are the 4 types of CAMs? - Answers Cadherins, NCAMs, Integrins, Selectins
What are the 3 types of CELL JUNCTIONS? - Answers 1. DEMOSOMES
2. TIGHT
3. GAP
What are TIGHT junctions? - Answers -tight seals between cells "kiss site"
Location: epithelial cells
Action: no movement
What are GAP junctions? - Answers -2 connexons form intracellular water soluble tunnel (1
connexon is 6 connexon proteins)
Location: cardiac/smooth muscle
Action: communication
What are DESOSOMES? - Answers -plaques connected by glycoproteins creating junctions
What is a SET POINT? - Answers -the range/point that a variable physiological state stabilizes
(normal range)
What are 3 components of the HOMEOSTATIC CONTROL SYSTEM? - Answers sensor
integrator
effector
What does an SENSOR do? - Answers detects environmental variable change
What does an INTEGRATOR do? - Answers compares variable to set point
What does an EFFECTOR do? - Answers restores variable to set point
What is INTRINSIC regulation? - Answers S, I, E all within a tissue
ex: exercising skeletal muscle
What is EXTRINSIC regulation? - Answers S,I, E all outside of effected tissue
ex: most homeostatic control systems
What is NEGATIVE FEEDBACK? - Answers once set point is restored, system stops/reverses
signalling to halt action
ex: most homeostatic control systems
What is POSITIVE FEEDBACK? - Answers amplifies signalling output to increase desired
outcome (not homeostatic)
What are the 6 components of the CELL MEMBRANE - Answers 1. plasma membrane
2. phospholipid bilayer
3. cholesterol
4. membrane proteins
5. ion channels
,6. carb chains
What is the function of the PLASMA MEMBRANE? - Answers -barrier that separates cells
internal from external environment
What are the 3 primary functions of the PLASMA MEMBRANE? - Answers 1. ensure cells survive
2. maintain homeostasis
3. communicate w surrounding cells
TRUE OR FALSE: phospholipids have non-polar heads and polar tails - Answers FALSE
*polar head, NP tails
TRUE OR FALSE: phospholipids have hydrophillic heads and hydrophobic tails - Answers true
What is the function CHOLESTEROL in the cell membrane? - Answers -prevents carb chains
from packing to tightly
-maintains membrane fluid
-located between phospholipids
What is the function MEMBRANE PROTEINS in the cell membrane? - Answers -cell
structure/function
-cell signalling
-transport
What is the function ION CHANNELS in the cell membrane? - Answers -specialized channels
that permit entry/exit of ions
What is the function CARB CHAINS in the cell membrane? - Answers -cell receptors
-stabilize membrane
, -transport
What is the FLUID MOSAIC MODEL? - Answers -describes cell membrane structure as a flexible,
dynamic bilayer of phospholipids with embedded proteins that move laterally. The "fluid" part
refers to the mobility of lipids and proteins within the membrane, while the "mosaic" represents
the diverse proteins scattered throughout. Components like cholesterol and carbohydrates also
contribute to membrane stability and function. This model highlights the membrane's role in
regulating the movement of substances and facilitating cell communication.
What are 3 types of CELLULAR ADHESIONS? - Answers -extracellular matrix (ECM)
-cell adhesion molecules (CAMs)
-cell junctions
What are the 3 components of the ECM? - Answers -interstitial fluid surrounding all cells
composed of: COLLGEN (tensile), ELASTIN (stretch/recoil), and FIBRONECTIN (promotes
adhesion)
What are CAMs? - Answers -transmembrane proteins who's intracellular side composes the
cytoskeleton and extracellular side faces the ECM
What are the 4 types of CAMs? - Answers Cadherins, NCAMs, Integrins, Selectins
What are the 3 types of CELL JUNCTIONS? - Answers 1. DEMOSOMES
2. TIGHT
3. GAP
What are TIGHT junctions? - Answers -tight seals between cells "kiss site"
Location: epithelial cells
Action: no movement
What are GAP junctions? - Answers -2 connexons form intracellular water soluble tunnel (1
connexon is 6 connexon proteins)
Location: cardiac/smooth muscle
Action: communication
What are DESOSOMES? - Answers -plaques connected by glycoproteins creating junctions
