Control In The Human Body Flashcards
WHY DOES WATER CONTENT IN THE BODY NEED TO BE CONTROLLED
Water content needs to be controlled to protect cells from either too much water entering or too much water leaving them
HOW IS WATER CONTENT CONTROLLED BY WATER LOSS FROM…
The lungs, skin, passing urine
The lungs — when we exhale
The skin — through sweating
Passing Urine — produced by kidneys
WHY DOES TEMPERATURE NEED TO BE CONTROLLED IN THE BODY
Temperature is controlled to maintain the temperature at which enzymes worm best
HOW IS BODY TEMPERATURE CONTROLLED
- sweating
- shivering
- controlling blood flow to the skin
WHY DO BLOOD SUGAR LEVELS NEED TO BE CONTROLLED IN THE BODY
blood sugar levels are controlled to provide cells with a constant supply of energy
HOW ARE BLOOD SUGAR LEVELS CONTROLLED
By the release and storage of glucose controlled by insulin
WHAT ARE HORMONES AND WHAT DO THEY DO
- Hormones are chemicals secreted by glands in the body
* Hormones co-ordinate many processes in the body
WHAT HORMONE DOES THE ADRENAL GLAND SECRETE
hormone, target organs, effect
Hormone — adrenaline
Target organs — vital organs. E.g Liver and heart
Effect — prepares the body for action
WHAT HORMONE DOES THE OVARY SECRETE
hormone, target organs, effect
Hormone — oestrogen
Target organs — ovaries, uterus, pituitary gland
Effect — controls puberty and menstrual cycle in females
WHAT HORMONE DOES THE PANCREAS SECRETE
hormone, target organs, effect
Hormone — insulin
Target Organs — liver
Effect — controls blood sugar levels
WHAT HORMONE DOES THE TESTES SECRETE
hormone, target organs, effect
Hormone — testosterone
Target organs — male reproductive organs
Effect — controls puberty in males
WHAT HORMONE DOES THE PITUITARY GLAND SECRETE
hormone, target organs, effect
Hormone — luteinising hormone (LH)
Target organs — ovaries
Effect — triggers egg release and progesterone production in ovaries
(1 of 2)
WHAT HORMONE DOES THE PITUITARY GLAND SECRETE
hormone, target organs, effect
Hormone — anti-diuretic hormone (ADH)
Target organs — kidney
Effect — controls blood water levels by triggering uptake of water in kidneys
(2 of 2)
WHAT HORMONE DOES THE PITUITARY GLAND SECRETE
hormone, target organs, effect
Hormone — follicle stimulating hormone (FSH)
Target organs — ovaries
Effect — triggers egg ripening and oestrogen production in ovaries
WHAT IS THE CONTRACEPTIVE PILL
What does it contain
The contraceptive pill greatly reduces the chances mature eggs being produced
- it contains oestrogen and progesterone (another hormone)
- these hormones inhibit the production of FSH, which in turn stops eggs maturing in the ovaries
WHY DOES THE MODERN DAY CONTRACEPTIVE PILL CONTAIN LESS OESTROGEN
It now contains less oestrogen because it caused women to have significant side effects such as:
- change in weight
- change in blood pressure
- change in mood
WHAT IS THE FERTILITY DRUG
Some women have difficulty becoming pregnant because they don’t produce enough FSH to allow their eggs to mature
• fertility drugs contain more FSH to stimulate eggs to mature in the ovaries
WHAT IS IVF TREATMENT AND HOW IS IT DONE?
IVF is a treatment used if a couple is having trouble conceiving a child
- the egg is fertilised outside of the woman’s body
- it is then implanted back into her uterus
Control in plants
WHAT IS PHOTOTROPISM
A plants direct response to light
- plant stems exhibit positive phototropism because they are growing towards the light
- auxins on the dark side makes the cells grow longer meaning they bend towards the light
Control in plants
WHAT IS GRAVITROPISM
A plants direct response to gravity
- negative gravitropism = where plants grown away from gravity (up)
- positive gravitropism = where plants grow towards gravity (down)
You get positive gravitropism in roots because there is a high concentration of auxins which will inhibit growth (on the lower side of the root)
WHEN ARE PLANT GROWTH HORMONES USED
Are used in agriculture and horticultures as weed killers and as rooting hormones
WHY DO SELECTIVE WEED KILLERS CONTAIN HORMONES
As it contains hormones it causes the weeds to grow too quickly and then die
