Lecture 1 : Cell to Cell communication

Question 1

Homeostasis

Answer 1

Any automatic processes that allow an animal to maintain equlibrium internally with external forces. IE body temp in endotherms

Question 2

Cell to Cell communication

Answer 2

Cell to cell commmunication is the basis of homeostasis, as it allows for animals to respond to enviromental and internal changes.

Question 3

Three mechanisms of Cell to Cell communicatoin

Answer 3

Negative feedback

Positive feedback

feedforward Control

Question 4

Two kinds of cell to cell communication

Answer 4

Long-distance: Endocrine, nervous system, and neuroendocrine system

Short distance: Paracrine, autocrine

Question 5

Cell to Cell communication: Endocrine system

Answer 5

1. Hormones are secreted from glands or sercatory cells into the blood stream
2. hormones travel through the blood stream contacting most cells they come accross
3. only cells with the correct receptors respond! cells w/o or with diffrent receptors do not!
4. response initiated
5. this proces is slow!

Question 6

Cell to Cell communication: Nervous system

Answer 6

1. Electrical energy travels through specalized cells (neurons).
2. Neurons release neurotransmitter accross small gap to target cell
3. Has effect on target cell, if said cell has a receptor
4. This process is FAST

Question 7

Cell to cell communication: neruoendocrine system

Answer 7

1. Electrical energy travels through specalized cells (neurons).
2. Neurons neurohormones into the blood

3.neurohormones travel through the blood stream contacting most cells they come accross

4. only cells with the correct receptors respond! cells w/o or with diffrent receptors do not!
5. response initiated
6. slow to medium speed

Question 8

Ionic Enviroments

Answer 8

Animals live in a varity of ionic enviroments:

Ocean: ~1000 mOsm

Freshwater: <15 mOsm

Air: N/a for the most part

Question 9

Important Ions

Answer 9

K+ = Potassium

Na+ = sodium

Ca++ = Calcium

Cl- = Chlorine