Homeostasis questions

  • Created by: Georgia56
  • Created on: 12-04-18 11:45
State 3 examples of stimulus and a corresponding response in animals.
Blinking when an object moves close to the eye; sweating when it gets too hot; eating when hungry.
1 of 21
For each E.g. suggest whether its a neural of hormonal system that is involved and why.
Blinking uses the neuronal system as it needs to be rapid; sweating uses the hormonal system as it is a longer-term response – it must be continued until you are cool; eating also uses the hormonal system as it is not a rapid response.
2 of 21
Describe 2 examples of as stimulus and response in plants.
Bending towards the light; opening stomata when it gets light.
3 of 21
List the organs associated with excretion.
Kidney; lungs; liver; skin.
4 of 21
List the organs associated with maintaining internal environment of a mammal, stating what role each organ plays.
Heart – pumps blood; blood vessels – deliver blood to organs; liver – metabolises many substances and stores sugars, etc.; kidney – excretion of metabolites; lungs – excretion of carbon dioxide; skin – temperature control; brain – coordination...
5 of 21
There is more...
adrenal gland, thyroid glands, pancreas, etc. – release hormones.
6 of 21
Explain why a good communication system must cover the whole body.
So that actions of all cells and tissues in body can be coordinated.
7 of 21
Explain why a good communication system must enable specific communication.
So that only the cells that need to respond will respond to the signal
8 of 21
Explain why a good communication system must enable rapid communication and enable both short- and long-term responses.
To enable response to rapid changes in the environment. So that the response can be suited to the environmental change – a short-term change in the environment only requires a short-term response, but other changes may require a long-term response.
9 of 21
Define the term homeostasis
The maintenance of a constant internal environment despite changes in external and internal factors.
10 of 21
Why is it essential to maintain body temperature?
To keep enzymes at their optimum temperature. Changes can have dramatic effect upon activity of cell processes. Temp rises- increase kinetic energy, more collisions. Essential chemical reactions occur more quickly. Cooler conditions- slow down.
11 of 21
Why is it essential that blood glucose concentration is maintained?
to supply sufficient glucose to tissues for respiration without decreasing the water potential of the blood too much.
12 of 21
Why is it essential that blood salt concentration is maintained?
to maintain the water potential of the blood and to maintain blood pressure.
13 of 21
Why is it essential that water potential of the blood is maintained?
to maintain blood pressure and to ensure cells are in the correct conditions.
14 of 21
Why is it essential carbon dioxide concentration is maintained?
carbon dioxide reacts with water to form an acid; a change in pH could alter protein structure and affect enzyme activity.
15 of 21
Why is it essential that blood pressure is maintained?
to ensure it is high enough to deliver blood efficiently, but without damaging blood vessels.
16 of 21
What is the role of sensory receptors and effects?
SENSORY- To detect changes in the environment. EFFECTORS-To carry out a response.
17 of 21
what is meant my input and output?
Input is the information sent from the sensory receptors to the coordination centre about changes in the environmental conditions. Output is the information sent by the coordination centre to the effectors.
18 of 21
Explain the difference between negative feedback and positive feedback.
Negative feedback occurs where the change in conditions detected by the sensory receptors is reversed by the action of the effectors. Positive feedback occurs where the initial change in conditions is increased by the action of the effectors.
19 of 21
Describe and explain the effect of positive feedback on the animal if its body temperature rises too high.
Temp rises rate of chemical reactions increases. This increases the release of heat from these reactions. As a result the animal gets even warmer. This speeds up the chemical reactions even more. Causes heat stroke, enzymes may denature & animal dies
20 of 21
Explain why body temperature must be controlled.
Cell activities depend upon enzyme activity. All enzymes have an optimum temperature. Too low and they work too slowly, too high and they become denatured.
21 of 21

Other cards in this set

Card 2

Front

For each E.g. suggest whether its a neural of hormonal system that is involved and why.

Back

Blinking uses the neuronal system as it needs to be rapid; sweating uses the hormonal system as it is a longer-term response – it must be continued until you are cool; eating also uses the hormonal system as it is not a rapid response.

Card 3

Front

Describe 2 examples of as stimulus and response in plants.

Back

Preview of the front of card 3

Card 4

Front

List the organs associated with excretion.

Back

Preview of the front of card 4

Card 5

Front

List the organs associated with maintaining internal environment of a mammal, stating what role each organ plays.

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Human, animal and plant behaviour resources »