BIOL3204 CH 6 COMMUNICATION, INTEGRATION, AND
HOMEOSTASIS EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED
Types of physiological signals include
Intracellular
Electrical
Chemical
- local vs long-distance
Intracellular signaling
Often in response to an external signal (first messenger")
E.g., Hormone
Complex intracellular signaling pathways work through
Second messengers
CAMP, 1P3, Ca2+, other ions (Na, Cl, K*)
Electrical signals
Includes changes in the membrane potential of a cell
- can be local or long distance
, Depolarization
The process during the action potential when sodium is rushing into the cell causing the
interior to become more positive.
Action potential
a neural impulse; a brief electrical charge that travels down an axon
Chemical signals
Secreted by cells into ECF
• Responsible for most communication within the body
• Chemical signals are ligands
Local chemical signals include
Gap junction signals - form direct cytoplasmic connections between adjacent cells
Contact- dependent signals- require interaction between membrane molecules on two
cells
Chemical signals diffuse throughout ECF to act on nearby cells
Autocrine vs Paracrine
Autocrine- acts on the same cell that secreted them
Paracrine- are secreted by one cell and diffused to another
Long distance chemical signals include
- Chemical = Endocrine
- Electrical = Action potential
Endocrine releases a BLANK into the blood stream
HOMEOSTASIS EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED
Types of physiological signals include
Intracellular
Electrical
Chemical
- local vs long-distance
Intracellular signaling
Often in response to an external signal (first messenger")
E.g., Hormone
Complex intracellular signaling pathways work through
Second messengers
CAMP, 1P3, Ca2+, other ions (Na, Cl, K*)
Electrical signals
Includes changes in the membrane potential of a cell
- can be local or long distance
, Depolarization
The process during the action potential when sodium is rushing into the cell causing the
interior to become more positive.
Action potential
a neural impulse; a brief electrical charge that travels down an axon
Chemical signals
Secreted by cells into ECF
• Responsible for most communication within the body
• Chemical signals are ligands
Local chemical signals include
Gap junction signals - form direct cytoplasmic connections between adjacent cells
Contact- dependent signals- require interaction between membrane molecules on two
cells
Chemical signals diffuse throughout ECF to act on nearby cells
Autocrine vs Paracrine
Autocrine- acts on the same cell that secreted them
Paracrine- are secreted by one cell and diffused to another
Long distance chemical signals include
- Chemical = Endocrine
- Electrical = Action potential
Endocrine releases a BLANK into the blood stream
