Controlling Body Temperature Flashcards
What’s the optimum temperature for enzymes in the body?
37 °C.
What does the body have to balance to keep the body temperature constant?
The amount of energy gained (e.g. through respiration) and lost.
Explain the area of the brain that controls body temperature.
There is a thermoregulatory centre in the brain, which contains receptors that are sensitive to the temperature of the blood flowing through the brain.
The thermoregulatory centre also receives impulses from temperature receptors in the skin, giving information about skin temperature.
What is the process that happens when the body warms up/cools down?
Temperature receptors detect that core body temperature is too high/too low.
The thermoregulatory centre acts a coordination centre - it receives information from the temperature receptors and triggers the effectors automatically.
Effectors, e.g. sweat glands, produce a response and counteract the change.
How do some effectors work?
Antagonistically, e.g. one effector heats and another cools - they’ll work at the same time to achieve a very precise temperature. This mechanism allows a more sensitive response.
What responses are produced by effectors to counteract an increase in body’s temperature?
When you’re too hot:
- Sweat is produced by sweat glands and evaporates from the skin. This transfers energy to the environment.
- The blood vessels supplying the skin dilate so more blood flows close to the surface of the skin. This is called vasodilation. This helps transfer energy from the skin to the environment.
When you’re too cold:
- Hairs stand up to trap an insulating layer of air.
- No sweat is produced.
- Blood vessels supply ign skin capillaries constrict to close off the skin’s blood supply. This is called vasoconstriction.
- When you’re cold you shiver too (your muscles contract automatically). This needs respiration, which transfers some energy to warm the body.
