B11 - Hormonal coordination Flashcards
What is the Endocrine system
It is made up of glands which release hormones
What glands make up the endocrine system
Pituitary Gland Thymus Thyroid gland Adrenal Pancreas Ovary Testes
What is a hormone
A chemical messenger
What is the Pituitary Gland
It is the master gland
It secretes hormones which control other glands
How is a higher blood glucose level dealt with
Detected by the pancreas
Pancreas secretes insulin into the blood
This causes the cells to take up glucose
It is stored as glycogen in the liver and muscle cells
How is a lower blood glucose level dealt with
Detected by the pancreas
Pancreas secretes glucagon
In liver cells, glycogen is broken down into glucose and released into the blood
What is type 1 diabetes
A disorder in which the pancreas fails to produce sufficient insulin.
It is identified by uncontrolled high blood glucose levels and is treated with insulin injections
What is type 2 diabetes
It is where the body cells no longer respond to insulin produced by the pancreas
It is treated with a healthy diet and regular exercise
Where is adrenaline produced
The adrenal gland
What is adrenaline
It is the ‘fight or flight’ hormone which is released when you are stressed, frightened or angry
It is not controlled by negative feedback
It increases heart rate and increases the delivery of oxygen and glucose to the brain and muscles
What does adrenaline cause
Increased heart rate Increased breathing rate Glycogen is converted to glucose Increase blood flow Pupils dilate
Where is thyroxine produced
Thyroid gland
What does thyroxine do
Stimulates the basal metabolic rate
Helps with growth and development
How is too much thyroxine dealt with
Detected by receptors and the level of TSH falls
How is too little thyroxine dealt with
Detected by receptors causing an increases in the amount of TSH released by the pituitary gland
TSH stimulates the production of thyroxine in the pituitary gland
What does FSH do
It causes the egg to mature in the ovary
It stimulates the production of Oestrogen
What does Oestrogen do
Stimulates the build up of the lining of the uterus
Stimulates the production of LH
Inhibits the production of FSH
What does LH do
Causes the egg to be released from the ovary
Inhibits the production of FSH
What does Progesterone do
Maintains the lining of the uterus
Inhibits the production of LH
What happens in the IVF process
Women given FSH and LH to stimulate eggs
Eggs are collected and fertilised by sperm
Fertilised eggs develop into embryos
When they are balls of cells 1 or 2 embryos are inserted into the womb
What are the advantages of IVF
People can have babies
Screened for diseases
Used embryos for stem cell research
What are the disadvantages of IVF
Open to misuse in the future
Stressful
Multiple births
People disagree with embryos being created and destroyed
What is a tropism
It is a growth in response to a stimulus
What is phototropism
Growth in response to light
Shoots will grow towards the light
Positive phototropism
