Control In The Human Body Flashcards Preview

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Flashcards in Control In The Human Body Deck (22):
1




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

2




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

3




WHY DOES TEMPERATURE NEED TO BE CONTROLLED IN THE BODY

Temperature is controlled to maintain the temperature at which enzymes worm best

4




HOW IS BODY TEMPERATURE CONTROLLED

• sweating
• shivering
• controlling blood flow to the skin

5




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

6




HOW ARE BLOOD SUGAR LEVELS CONTROLLED

By the release and storage of glucose controlled by insulin

7




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

8




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

9




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

10




WHAT HORMONE DOES THE PANCREAS SECRETE

hormone, target organs, effect

Hormone — insulin

Target Organs — liver

Effect — controls blood sugar levels

11




WHAT HORMONE DOES THE TESTES SECRETE

hormone, target organs, effect

Hormone — testosterone

Target organs — male reproductive organs

Effect — controls puberty in males

12




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

13

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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

14

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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

15




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

16




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

17




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

18




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

19

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

20

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)

21




WHEN ARE PLANT GROWTH HORMONES USED

Are used in agriculture and horticultures as weed killers and as rooting hormones

22




WHY DO SELECTIVE WEED KILLERS CONTAIN HORMONES

As it contains hormones it causes the weeds to grow too quickly and then die