B3.3 Flashcards
What happens if body temperature is below 37?
1) enzymes react too slowly
2) respiration doesn’t release enough energy, cells begin to die
3) rail of hyperthermia with temperatures under 35
What happens if body temperature is above 37?
enzymes denature so body reactions cannot occur
What is the thermoregulatory system?
In the brain, responsible for hell regulating body temperature
Received signals from receptors in the skin to detect stimuli
What happens when you’re too hot?
1) Sweat glands produce sweat - cools the skin as the water evaporates
2) Hair erector muscles relax/ lay flat - prevents an insulating layer of air to be trapped around the body
3) Vasodilation - the capillaries are supplied with a greater volume of blood, which then loses heat to the environment via radiation. Th e arterioles that lead to the capillaries contract and relax to allow more or less blood to flow through
During vasodilation the arterioles relax and dilate to allow more blood to flow through, skin can seem flushed
What happens when you’re cold?
1) Sweat glands stop producing sweat
2) Hair erector muscles contract/stand up straight allowing an insulating layer of air to be trapped
3) Shivering - muscles contract and relax quickly so cells respire quickly and transfer more heat energy
4) Vasoconstriction - arteriole muscles contract allowing less blood to the surface so less heat is lost by radiation
What is insulin?
A hormone released when blood sugar levels are too high detected by the pancreas
Travels in the blood to the liver where glucose is stimulates to covert into glycogen
What is glucagon?
Hormone released when blood glucose concentration is too low
Makes the liver turn the glycogen back into glucose
What is type 1 diabetes?
When a person cannot produce insulin as they’re own immune system has destroyed the pancreatic cells
- begins in childhood
- controlled by regular injections of insulin
- should eat a balanced diet and exercise regularly
What is type 2 diabetes?
When a person cannot effectively use insulin
- Either not enough insulin is produced or cells don’t respond to the insulin
- Occurs later in life, effect of obesity
- controlled by regulating a diet
How is water lost through the body?
- sweat
- urine
- when exhaling (as water vapour)
What are the effect of too little or too much water in blood?
- too much means water will move into your blood cells causing them to swell and burst (lysis)
- too little means water will diffuse out of the blood cells causing them to shrink or crenate
What is urine?
Solution containing:
- water
- urea (toxic)
ADH? KIDNEY?
LOOK AT SHEET IN BIO BOOK
PLEASE
What does hypertonic mean?
Contains high levels of sugar and salts
What does hypotonic mean?
Contains low levels of glucose and salts
