B11 - Hormonal Coordination

Cards (16)

  • Hormone - A chemical messenger than can cause a response
  • Glands in the Body -Hypothalamus
    • Found in the brain
    • Steadies body temperature
  • Glands in the Body - Pituitary Gland
    • Produces many different hormones
    • Controls when we enter puberty and when to stimulate hormones to make us grow
  • Glands in the Body - Thyroid Gland
    • Found in the neck
    • Controls our metabolism
  • Glands in the body - Adrenal Gland
    • Found above the pancreas
    • Stimulates adrenaline
  • Glands in the body - Pancreas
    • Controls blood sugar levels
    • Produces insulin
  • Glands in the body - Ovaries
    • Produces oestrogen
  • Glands in the body - Testes
    • Produces testosterone
  • Negative Feedback:
    • Body detects whether something is too high or too low of a level
    A) Receptor
    B) Response lowers level
    C) Response raises level
  • Blood Glucose
    • When sugar levels are too high
    • Pancreas releases insulin
    • Cells take in glucose
    • Glucose is stored in liver as glycogen
    • When sugar levels are too low
    • Pancreas releases glycogen
    • Cells release glucose
    • Glycogen converts to glucose
  • Diabetes
    • Type 1
    • Often born with
    • Pancreas doesn't produce enough insulin
    • Treated with insulin injections
    • Type 2
    • Developed over time
    • Developed from obesity or a high sugar diet
    • Pancreas stops responding to insulin
    • Diet and exercise must be carefully controlled to treat it
  • The Menstrual Cycle
    • Days 1-7
    • Menstruation (bleeding) occurs
    • Days 8-13
    • Oestrogen levels increase
    • Builds up uterus lining
    • Day 14
    • Ovulation occurs
    • Caused by Luteinizing hormone (LH) and follicle stimulating hormone (FSH)
    • LH releases the egg
    • FSH matures the egg
    • Day 22-23
    • Progesterone is released which keeps uterus lining thick
    • When an egg is fertilised, progesterone levels remain high to ensure menstruation doesn't happen
  • Contraceptives:
    • Barrier
    • Work on the principle of sperm not reaching the egg
    • Types include condoms and rubber cup
    • No side effects
    • Prevents STD's
    • May be faulty and sperm can still get through
    • Chemical
    • The pill - controls hormone levels (prevents FSH being released therefore egg cannot be matured)
    • Can cause hormonal side affects
    • Spermicidal gel
    • Kills sperm
    • Coil (IUD)
    • Slowly releases progesterone to keep uterus lining thick
  • IVF:
    • FSH & LH injections
    • Eggs are collected
    • Eggs are then fertilised with male sperm
    • Implant zygote into uterus
    • Progesterone is injected throughout to keep uterus lining thick
  • Auxins:
    • Phototropism - when a plant grows towards the light source
    • Auxins go to the side of the plant that is closest to the light which causes that side to grow faster since they are growth hormones
    • This causes the plant to bend towards the light
    • Gravitropism
    • Causes the roots to grow away from the light
    • Auxins gather on the side furthest away from the light which causes it to bend away from the light
  • Farmers using hormones
    • Auxins
    • Used in fertilisers to maximise size and speed that the plant grows
    • Used in weed killers since the weeds cannot take in enough minerals or water to grow meaning they die
    • Gibberellins
    • Seeds germinate quicker
    • Meaning the farmer can grow more crop
    • Ethene
    • Causes plants to ripen quicker