5.1.1: Communication And Homeostasis Flashcards
What is thermoregulation?
The ability to regulate body temperature essential for survival.
What happens if body temperature drops too low?
Insufficient kinetic energy for enzyme-controlled reactions.
What occurs if body temperature increases too high?
Enzymes denature, potentially leading to cell death.
Define ectotherms.
Animals that cannot regulate their internal temperature and rely on behavioral changes.
Which types of animals are typically ectotherms?
- Fish
- Amphibians
- Reptiles
- Invertebrates
Why do ectotherms in aquatic environments have less need to regulate temperature?
Water has a high specific heat capacity, maintaining a relatively constant temperature.
How do terrestrial ectotherms regulate their temperature?
By basking on hot rocks or surfaces to absorb heat.
What are some behavioral responses ectotherms use to warm up?
- Basking on warm ground
- Contracting muscles
- Vibrating to raise body temperature
What actions do ectotherms take to cool down?
- Moving to the shade
- Moving into water
- Digging underground
- Lying on colder surfaces
Define endotherms.
Animals that can regulate their own body temperature through a nervous response.
What role do peripheral temperature receptors play in endotherms?
They detect changes in external temperature and send impulses to the hypothalamus.
What is the function of the hypothalamus in thermoregulation?
It coordinates impulses from sensory neurons and triggers responses in skin glands and muscles.
What happens when an endotherm is too hot?
- Sweat glands produce more sweat
- Vasodilation occurs
What is the cooling effect of sweating?
Evaporation of sweat removes heat from the skin due to high latent heat of vaporization.
What occurs during vasodilation?
Arterioles near the skin surface dilate, allowing more blood flow to radiate heat.
What happens when a decrease in temperature is detected by endotherms?
- Less sweat is produced
- Vasoconstriction occurs
What is vasoconstriction?
Arterioles near the skin surface restrict, reducing blood flow and heat loss.
What is the purpose of shivering in endotherms?
To contract and relax muscles, increasing respiration and generating heat.
How do some animals use fur or feathers to regulate temperature?
- Raise fur to trap air and insulate
- Lower fur to reduce insulation
What controls the raising and lowering of fur in animals?
Erector pili muscles in the skin.
What behavioral modifications can endotherms use to regulate temperature?
- Moving to the shade
- Removing clothes
- Fanning themselves
- Huddling for warmth
