homeostasis and body fluids

Question 1

intercellular fluid

Answer 1

• many enzymes and ions in solution

- inside cell is negatively charged compared to outside

Question 2

homeostasis definition;

Answer 2

-maintenance of an internal environment within restricted limits in organisms

Question 3

homeostasis cycle:

Answer 3

1. ) stimulus (produces change in variable)
2. ) receptor (detects change)
3. ) input (info is sent along afferent pathway to control center)
4. ) output: info is sent along efferent pathway to effector
5. ) response: of effector leads back to reduce the effect of the stimulus and returns variable to homeostatic level.

Question 4

control mechanisms:

Answer 4

• optimum point
• receptor
• coordinator
• effector
• feedback mechanism

Question 5

optimum point

Answer 5

the point at which the system operates best. this is monitored by receptors

Question 6

receptor:

Answer 6

detects any deviation from the optimum point i.e a stimulus and informs the co-ordinator

Question 7

co-coordinator

Answer 7

which co ordinates info from the receptor and send instructions to the appropriate effector

Question 8

effector

Answer 8

the effector is often a muscle or gland, which brings about changes needed to return the system back to the optimum point. this return to normality creates a feedback mechanism.

Question 9

feedback mechanism

Answer 9

a feedback mechanism is a receptor that responds to a stimulus created by the change to the system brought about by an effector.

Question 10

negative feedback mechanism:

Answer 10

the response causes a change in the opposite direction to the original stimulus. Returning the sytem to normal e.g glucose and temp control

Question 11

positive feedback mechanism:

Answer 11

the response causes a change in the same direction as the original stimulus. this further enhances the change e.g oxytocin inducing contractions during birth or lactation.

Question 12

examples of homeostasis:

Answer 12

• temperature/thermoregulation
• glucose in the blood
• bacteria and viruses in the lymphatic system
• maintenance of healthy BPA
• maintaining balance of water

Question 13

what is responsible for homeostasis

Answer 13

hypothalamus