Topic 5- Homeostasis Keywords Flashcards
Homeostasis
The regulation of internal conditions to maintain optimum conditions in response to changes
Stimulus
A change in the environment
Receptors
Cells that detect changes in the environment
Coordination centres
Receive and process information from receptors. E.g. brain
Effectors
Muscles or glands which bring about a response
Reflex action
An automatic and rapid action
Endocrine system
Consists of glands that release hormones into the blood to get to a target organ to cause a response
Insulin
Released from the pancreas in response to high blood glucose levels and causes glucose to move from the blood into the cells. It causes glucose to be converted into glycogen for storage in the liver
Glucagon
Released from the pancreas in response to low blood glucose levels and causes glycogen to be broken down into glucose and released back into the blood
Type 1 diabetes
When the pancreas does not produce enough insulin
Type 2 diabetes
When the body cells no longer respond to insulin
Oestrogen
Released by the ovaries. Stops FSH being released and stimulates LH to be released
Follicle stimulating hormone (FSH)
Hormone released by the pituitary gland. Causes maturation of the egg in the ovary.
Luteinising hormone (LH)
Hormone released by the pituitary gland. Causes the egg to be released from the ovary.
In vitro fertilisation (IVF)
Where egg cells are fertilised outside of the body with sperm cells
Cerebral cortex
The outer part of the brain responsible for intelligence, language, memory and consciousness
Medulla
Controls unconscious activities such as heart rate and breathing rate
Cerebellum
Controls balance, co-ordination of movement and muscular activity
MRI
Brain scanning technique
Accommodation
The process of changing the shape of the lens to focus on near or distant objects
Myopia
Short-sightedness
Hyperopia
Long-sightedness
Vasodilation
When blood vessels supplying blood to the skin widen and allow more warm blood to flow near the surface of the skin, where the heat is lost to the air
Vasoconstriction
When blood vessels supplying blood to the skin narrow and allow less warm blood to flow near the surface of the skin, which reduces heat loss
Deamination
The removal of the amine group on amino acids to form urea
Selective reabsorption
When the useful substances are reabsorbed back into the blood from the kidney tubules
ADH
Hormone released from the pituitary gland which regulates the water concentration of the blood
Thyroxine
Hormone released from the thyroid gland which stimulates the basal metabolic rate
