Homeostasis (Edexcel GCSE Biology): Flashcards
📚Flashcards
Practise the cards
14 cards from this deck
ShowHide
Practise the cards
14 cards from this deck
Homeostasis definition
Homeostasis definition
Maintenance of constant internal environment in body
Optimal human body temp for enzyme function
Optimal human body temp for enzyme function
37°C
Effect on enzymes when temp >40°C
Effect on enzymes when temp >40°C
Enzymes denature - shape changes, can't catalyse reactions
How sweating cools body
How sweating cools body
Sweat evaporates, removing heat from body surface
How shivering warms body
How shivering warms body
Muscles contract rapidly to generate heat
Vasodilation in thermoregulation
Vasodilation in thermoregulation
Blood vessels widen to increase heat loss when hot
Vasoconstriction in thermoregulation
Vasoconstriction in thermoregulation
Blood vessels narrow to reduce heat loss when cold
Hypothalamus role in thermoregulation
Hypothalamus role in thermoregulation
Thermoregulatory centre - monitors & controls body temp
Dermis structures for thermoregulation
Dermis structures for thermoregulation
Sweat glands, blood vessels, nerve endings
Osmoregulation definition
Osmoregulation definition
Control of water levels & mineral ions in blood
Effect when water conc. too high outside cells
Effect when water conc. too high outside cells
Water moves in by osmosis, cells swell & may burst
Effect when water conc. too low outside cells
Effect when water conc. too low outside cells
Water moves out by osmosis, cells shrink & dehydrate
Kidneys role in osmoregulation
Kidneys role in osmoregulation
Filter blood, adjust water & ion reabsorption
ADH function
ADH function
Controls water reabsorption in kidneys