B11. Hormonal Control Flashcards
What is homeostasis?
Homeostasis is the regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes.
Define a gland
A gland is any organ that releases hormones
Define a hormone
A hormone is a chemical produced by a gland secreted into the bloodstream
where it travels in the blood to a target organ where a response occurs.
The pituitary gland is know as the ‘master gland’. Which hormones does the pituitary gland secrete?
Follicle stimulating hormone (FSH)
Luteinising hormone (LH)
Name the hormones that the pancreas gland secretes?
Insulin and glucagon
Which hormone is secreted by the thyroid gland and what is it’s function.
Hormone = Thyroxine
It controls metabolic rate and affects growth
Which hormone is secreted by the adrenal glands?
Adrenaline
What is the function of the hormone adrenaline?
It increases the heart rate and
boosts the delivery of oxygen and glucose to the brain and muscles preparing the body for ‘flight or fight’.
Explain how insulin regulates blood glucose levels?
Insulin lowers blood glucose levels by stimulating the liver and muscle cells to take in excess glucose and store it as glycogen.
Which gland detects changes in blood glucose levels?
Pancreas
Explain how the hormone glucagon causes blood glucose levels to rise.
Glucagon travels in the bloodstream to the liver (where there is a store of glucose).
The liver converts stored glycogen back into glucose.
Blood glucose levels therefore rise.
Which type of feedback controls blood glucose levels?
Negative feedback
What is meant by the term ‘negative feedback’?
Negative feedback involves a response that is thereverseof the change detected (it functions toreducethe change).
What is Type 1 diabetes?
Type 1 diabetes is a disorder in which the pancreas fails to produce sufficient insulin.
How might a Dr become aware that a patient has type 1 diabetes?
It is characterised by uncontrolled high blood glucose levels.
The patient may have glucose in their urine.
What is the treatment for type 1 diabetes?
It is normally treated with insulin injections (usually via insulin pump).
What is type 2 diabetes?
Type 2 diabetes is a disorder where the body cells no longer respond to insulin produced by the pancreas. So excess glucose is not absorbed.
How is type 2 diabetes usually controlled?
A carbohydrate controlled diet and an exercise regime are common treatments.
Name 3 symptoms of both type 1 and type 2 diabetes.
Frequent urination
Being really thirsty
Blurred vision
Name 2 risk factors for type 2 diabetes.
Lack of exercise
Obesity
Family history
Diet high in saturated fat
What is the function of the hormone FSH in controlling the menstrual cycle?
- it causes an egg to mature in an ovary.
- it stimulates the ovaries to release the hormone oestrogen.
What is the function of the hormone Oestrogen in controlling the menstrual cycle?
- Stimulates the lining of the uterus to grow ‘build up’ again after menstruation in preparation for pregnancy.
- Stimulates the pituitary gland to release LH.
- Inhibits the release of FSH, so that only one egg matures in a cycle.
What is the function of the hormone LH in controlling the menstrual cycle?
- Stimulates the release of a mature egg from the ovary.
- Stimulates the ovaries to release progesterone.
- Inhibits the release of Oestrogen.
What is the function of the hormone progesterone in controlling the menstrual cycle?
- Maintains the lining of uterus during second half of menstrual cycle and during pregnancy.
- Inhibits both FSH and LH.
What is infertility?
Infertility means being unable to conceive.
Name 2 possible causes of infertility?
- Problems with ovulation
- Low sperm count
- Male infertility
- Block fallopian tubes
- Underlying medical conditions
Which fertility drugs are given to women during IVF treatment?
Fertility drugs given to women are FSH and LH by injection.
What are the stage of IVF treatment?
IVF involves giving the mother fertility drugs (FSH and LH) to stimulate the maturation of several eggs.
The eggs are collected from the mother by a doctor and fertilised by sperm from the father in the laboratory.
The fertilised eggs divide and develop into embryos.
At the stage when they are tiny balls of cells, one or two embryos are inserted into the mother’s uterus (womb).
List 3 disadvantages of IVF treatment.
- Low success rate (approx 20-30%)ornot always successful
*High number of multiple births (can lead to low birth weight or harm to mother)
*Expensive
*Emotionally and physically stressful
*Side effects
