Topic 5 Homeostasis Flashcards
What is the pituitary gland and name examples of hormones it releases.
The master gland in the brain which makes and secrets hormones which travel to target organs in the blood stream. E.g FSH,LH,GH,ADH
Describe the role of ADH ,LH,FSH and GH
ADH-controls water content in blood
LH-Stimulates egg release(ovulation) in females and testosterone production in males.
FSH-Stimulates egg development and oestrogen production in females and sperm production in males.
GH-Speeds up grow to and development in children
Describe the process of thermoregulation
The normal body temperature is 37• C,during exercise/sun the body temp increases. This is detected by the hypothalamus, the body sweats to reduce the temp and is back to normal body temp.
During cold weather the normal body temperature decreases which is detected by the hypothalamus, body respires or hairs stick up to increase body temp to normal level.
Why does water need to be removed from the lungs, kidney or skin and where is it produced?
Produced during respiration, due to osmosis in cells to prevent shrinkage and bursting
Why must carbon dioxide be removed from the lungs and where is it produced?
It is produced during respiration and too much build up in the blood is too acidic therefore toxic when accumulated.
Why must urea be removed from the kids yes and where is it produced?
Urea is produced when protein breaks down amino acids and then into urea at the liver, urea is toxic when it builds up.
Reaction time required practical
See book
What is negative feedback?
When the body reverses a change to the control system in order to return to the set level.
What does adrenaline do?
Converts glycogen to glucose for respiration,pupils dilate,increased mental awareness, diverts blood in digestive system to muscles,increases heart/breathing rate
What are the three stages on the kidney?
1:Ultrafiltration-Filters glucose,urea,water and mineral ions into nephron.
2:Selective reabsorption-Reabsorbs all glucose and no urea.Dependent on osmosis for water and diffusion for mineral ions.
3:Collection-Collects urine and moved into bladder in ureter.
Describe the process of maintain normal water content
Too much water is detected by receptors in the brain,pituitary gland stops release of ADH.Less water reabsorption, large volumes of dilute urine.Back to normal water content
Too little water is detected by receptions in brain, pituitary gland releases ADH which causes the kidney tubules to reabsorb more water-smaller volume of concentrated urine.Back to normal water level
Label the kidney,eye etc
See book
Describe the process of blood glucose control.
The normals blood glucose level.Eating increased amount of glucose, which is detected by the pancreas.So insulin is released,which absorbs more glucose and converts the glucose to glycogen in the muscles and liver- background k normals glucose level.
Fasting or exercise decreases glucose level which is detected by the pancreas. Glucagon is released which converts glycogen in the muscles and liver into glucose.Back to normal glucose level.
Advantage and disadvantages of oral contraceptives such as the pill
+:convenient-easily stop taking them when desired
-:Less reliable when incorrectly taken
Advantage and disadvantage of injection/doin patch/implant
-Slow release of progesterone to inhibit maturation and release of eggs
+:Reliable/convenient-dont have to remember to take anything, easy to stop
-:Encourages promiscuity,doesn’t prevent STI’s, invasive to risk of infection
