Maintaning a balance glossary (1 Viewer)

[flipsyde]

Glossary of Terms- Maintaining a balance

Enzyme- A biological catalyst that speeds up controls metabolic reactions and lowers the activation energy

Homeostasis- The process by which organisms maintain a relatively stable core environment.

Detects change (receptors) > Feedback (nervous system) > central nervous system (brain) > effectors > Change counteracted > Negative feedback (reaction)


Negative feedback system- Makes changes that are opposite to the stimuli.

Receptors- Detect changes from the stable state

Control centre- Causes effectors to counteract changes from the stable state.

Nervous system- Co-ordinates the internal organ systems that are used in homeostasis. e.g. Temperature changes. It is a system that allows the co-ordinating of organs and responses to environmental changes.

Arteries- Carry oxygenated blood from the heart
- Muscle used to hold the blood in
- No valves
- Thick

Capillaries- Connect arteries to veins
- thin (about 1 cell thick)
- allows easy flow of nutrients and gases through

Veins- Carry deoxygenated blood from the body to the heart
- Thin walls
- valves present to prevent backflow

 

[withoutaface]

In addition:

Endotherm: An organism that regulates its own temperature, also known as warm blooded.
Ectotherm: An organsim that relies upon the outside environment to regulate its temperature.
Effector: Something which carries out the change necessary to return an aspect to its stable state.

 

[Tommy_Lamp]

Enantiostasis: The maintenance of metabolic and physiological functions despite changes in the external environment.

 

[ceasetehconfusn]

what's an endothelium? is that what they call the wall of veins/arteries..?

 

[acmilan]

The endothelium is the thin layer of cells that lines blood and lymph vessels.

Endothelial cells perform the following functions.

- They act as a selective barrier to the passage of molecules and cells between the blood and the surrounding bodily tissue. Endothelial cells make up the blood-brain barrier - the barrier between the central nervous system and the rest of the body.
- They play an essential role in summoning and capturing white blood cells (leukocytes) to the site of an infection.
- They play an important role in the mechanics of blood flow.
- They regulate coagulation of the blood at the site of a trauma.
- They regulate the growth of the veinous muscular cells.
- They control the contraction and relaxation of veins.
- They secrete and modify several veinous signalling molecules.

 

[ceasetehconfusn]

ahh it all seems clearer now, thank you