Homeostasis And Response 🧪 Flashcards
What are the names of the pills taken for contraception? What do they prevent?
TAKEN DAILY
Progesterone only pill - makes mucus thick and sticky so sperm cannot penetrate the egg
Combined pill- oestrogen and progesterone restricts FSH preventing the egg to mature
Positives and negatives of contraceptive pills?
Positive- effective
Negative - increased chance of breast cancer and blood clots
Have to take daily, if miss risk pregnancy
What are the 3 other contraceptions that contain progesterone
How long do they last?
Positives + Negatives ?
Patch - week
IUD implant -yearly prevent embryo from implanting
Injection - monthly
Positive more convenient
Neg- not protected from STI’s
What does progesterone do?
Stops eggs being released and maturing
What are the two barrier methods of contraception ?
Positive + Negative
Condom - reduced risk of STI’s
Diaphragm
Covered in spermicide- gel that kills sperm before it reaches the egg
What are the surgical procedures of contraception?
Sterilisation - tie Fallopian tubes preventing egg reaching uterus
Men- prevents sperm from leaving the penis
List all the forms of contraception
Abstinence
IUD
progesterone pill
Combined pill
Sterilisation
Patch
Injection 
What are the two ways to treating fertility?
Pill releases FSH (mature)
and LH allowing the egg to be released (ovulation)
IVF
What is phototropism?
When a plant shoots / grows toward the light
Explain the experiment that scientists do to show phototropism?
Remove tips of shoots
Does not grow toward light
Because hormone called auxins are at the tips causes the plant to bend towards the light
Concludes that the tips only produce auxins
What material do scientists put on the tip of the shoots ? What does it do? What can you conclude ?
Foil, prevents any light from being detected by auxins , so plant does not grow towards the light
Tell us that tips are sensitive to light.
What are the stages of shoots growing ? What do auxins trigger?
- Auxins produced on the tip of the shoot
Auxins trigger cell growth
- Light caused auxins to focus on the darker sides of the shoots
- Auxins now spread down the shoot, causing darker sides on the shoots cells to grow faster than cells on lighter sides.
- Causes shoots to grow towards the light
What is gravitropism?
What roots grow towards gravity
Explain how gravitropism occurs
Auxins are produced in the root
But gravity causes it to be concentrated on the lower side
This inhibits cell growth
Causing the lower side to grow more slowing than the upper side
Causing the roots to grow towards gravity
What does Auxins do in roots
Inhibits growth
Why is Gibberellins important?
Starts germination of seeds
Why is ethene important in plants ?
Controls cell division and the ripening of fruits
What are Auxins 3 main uses?
Weed killers in gardens
Rooting powders
promoting growth in tissue culture
What are gibberellins 3 used?
End seed dormancy - force a seed to germinate earlier
Encourage plants to flower
Make fruit grow larger
What are ethene’s use in fruit products?
Triggers ripening for goods in demand that were just picked and stored
What is kidney dialysis?
A machine that contains a semi permeable membrane.
Which mimics the nephron tubules.
When the patients blood passes over excess ions and urea diffuse from the high concentration of blood
into the low concentration of dialysis fluid.
Disadvantages of kidney dialysis
Takes 3-4 hours 3 times a week
Risk of blood clot/ infections
Expensive
Advantages of kidney Transplant?
Gives patient more time to find kidney donor
What happens if a patient is unable to receive kidney dialysis?
Tissues become damaged
Why are immunosuppressant given to patients recovering a donor kidney ?
They have to take it for life , it caused the body to not destroy foreign cells from the donated kidney
How can patients revive a donor?
From other registered donors who have recently died
or family members
Have to be a tissue match
Disadvantages of kidney transplants?
Kidneys can be rejected by the body
Need to take immunosuppressants for life making them
More prone to disease
Long waiting lists
Advantages of kidney transplant ?
Cheaper in the long run
Less time consuming
What is one affect of adrenaline
Dilated pupils
What is the best temp for the human body
37.4
How is bloods temperature changed within the body ?
Blood is cooled in the stomach and flows into the brain
How does decay occur in a heap of dead plants? What do the organisms do ?
Microorganisms digest enzymes and conduct aerobic respiration producing carbon dioxide relating nitrate
How does decay occur in plants?
Carbon dioxide is taken up by plants by diffusion via stomata and is used for photosynthesis to make glucose
What happened to nitrate in decay?
Taken up the roots by active transport to make amino acids to make phosphate for DNA
List and explain the parts of the eye
Sclera - hard outer layer protecting the eye
Ciliary muscle - works together w/
Suspensory ligament- controls the thickness of the lens for accommodation
Cornea- clear layer that refracts light
Pupil - whole that lets light through
Iris- controls the size of the pupils to prevent damage
Retina- detects light
Optic nerve- sends electrical signals to brain
Explain parts of the brain
Bottom -medulla - controls unconscious activities eg. Heart rate
Middle - cerebellum- controls muscle coordination
Top- cerebral cortex - controls consciousness and memory