Topic 7 - Animal Coordination, Control And Homeostasis Flashcards
Name the hormone, what they produce and how they are transported to their target organs
Pituitary gland - several hormones in response to body conditions eg, blood water levels
Thyroid gland - thyroxine
Pancreas - insulin
Adrenal glands - adrenaline
Ovaries - oestrogen
Testes - testosterone
How does adrenaline prepare the body for fight or flight?
Increased heart rate
Increased blood pressure
Increased blood flow to muscles
Raised blood sugar levels by stimulating the liver to change glycogen into glucose
How does thyroxine control metabolic rates as an example of negative feedback?
Low levels of thyroxine stimulates production of TRH in hypothalamus
This causes release of TSH from the pituitary gland
TSH acts on the thyroid to produce thyroxine
When thyroxine is levels are normal thyroxine inhibits the release of TRH and the production of TSH
Stages of the menstrual cycle
Day 1-7: FSH - pituitary gland, causes the egg to mature and stimulates the ovaries to release oestrogen
Day 7-14: oestrogen - ovaries, thickens the lining and stimulates the pituitary gland to release LH
Day 14-21: LH - pituitary gland, release of a mature egg
Day 21-28: progesterone- ovaries, maintains the uterus lining
How hormonal contraception influences the menstrual cycle and prevents pregnancy
Some prevent fertilised eggs from implanting in the womb
Thick and sticky muscus in the cervix to make movement for the sperm harder to reach the egg cell
Hormonal contraception vs barrier contraception
Hormonal:
The pill - stop egg being released from your ovaries each month
Vaginal ring - releases oestrogen and progesterone to prevent pregnancy
Barrier:
Condoms/ diaphragm - prevents the sperm from reaching the egg
IUD - prevent the implantation of an embryo or release of a hormone
Surgical methods - male or female sterilisation
Uses of hormones in ART including IVF and clomifene therapy
ART:
IVF - eggs and sperm are fertilised in a dish in the laboratory, then develop into embryos and are inserted into the mothers womb
Clomifene:
Contains FSH and LH to stimulate eggs to mature in the ovary
What is the importance of maintaining a constant internal environment in response to internal and external change?
Provide the cells with what they need to survive (oxygen, nutrients, and removal of waste) is necessary for the well-being of the cells and body
What is the importance of homeostasis?
Homeostasis - helps maintain a stable internal environment within our body
Thermoregulation - helps maintain a constant temperature
Osmoregulation - helps maintain a constant normal blood pressure
How thermoregulation takes place…
Dermis, epidermis, hypothalamus
The role of the dermis - raise skin hairs and traps a layer of insulating air next to the skin
The role of the epidermis - protects your skin from the outside world
The role of the hypothalamus - monitors the temperature of the body
Hoe thermoregulation takes place…
Shivering, vasoconstriction, vasodilation
Shivering - nerve impulses are sent from the hypothalamus sending rapid contractions that generate heat (raising the body temperature)
Vasoconstriction - blood vessels near the skin constrict allowing less blood to the skin surface therefore less heat is lost by radiation
Vasodilation - blood vessels near the skin dilate allowing more blood to the skin surface therefore heat can be lost by radiation
How does insulin control blood glucose concentration?
Insulin causes cells in the liver to convert glucose into glycogen absorbing glucose out of the blood
How is blood glucose concentration regulated by glucagon?
Glucagon triggers your liver to convert glycogen into a usable form and then release it into your blood stream
Causes of type 1 diabetes and how to control it
Your body can’t produce enough insulin
Injected insulin, watching your diet and exercise
Causes of type 2 diabetes and how to control it
Your body become immune to insulin
Carbohydrate diet and regular exercise
