Homeostasis Flashcards
(15 cards)
What is homeostasis?
Homeostasis is the maintaining of internal conditions at a constant level within an organism in response to change
What does the thermoregulatory centre do
The thermoregulatory centre monitors the body temperature by the receptors in the brain when the blood flows past them
What happens when your internal body temperature is high
Your body sweats, vasodilation-the blood vessels close to the skin dilate so heat can pass through the skin.
What happens when your internal body temperature is low
Homeostasis increases the temperature by decreasing the amount of sweating, shivering. Also the hairs on the body stand trapping thick layer of heat and vasoconstriction- less blood flow near skin.
What happens water levels are high in the body
Cells flood with water and homeostasis reduces the water by making you urinate more often
What happens when the water levels are low in the body
Less metabolic reactions happen and cells shrivel due to lack of water so homeostasis reduces water by less frequent urine with a higher concentration of urea
What does the body do when the glucose concentration is high
The pancreas secretes insulin which causes the cells to absorb the glucose they need and convert any excess glucose into glycogen which is stored in the liver causing the concentration to decrease
What does the body do when the glucose concentration is low
The pancreas secretes glucagon which converts glycogen in the liver to glucose causing the concentration to increase
What is a stimuli
Any change in the internal and external environment of an organism(e.g internal- glucose or water external- pitch of sound)
What is a receptors
Cells that detect change in environment/ stimuli which leads to a response
What are coordination center
Brain, spinal cord and pancreas that receive information from receptors and decide on an appropriate response. Once they decide a response they send it to the effectors
What are effectors
Effectors can be glands or muscles in the body that carry out response decides by the coordination centre
Which 2 things make up the central nervous system
The brain and the spinal cord
What makes up the peripheral nervous system
All neurones and bundles of neurones( ganglia) around the body
What is the functions of neurons
They are the main cells in sending and receiving information from the receptors to the effectors
