Thermoregulation

What are the four internal sources of heat production?

Heat of metabolism, muscle activity (exercise/shivering), non-shivering thermogenesis, heat of fermentation from rumen

What are the two external sources of heat production?

Solar radiation and environment (when hotter than body temperature)

What are the four mechanisms of heat transfer?

Radiation, evaporation, conduction, convection

What environmental factors influence heat transfer?

Temperature of surroundings, air temperature, air humidity, air movement

What are five factors that influence heat loss?

Body surface area, body covering, moisture evaporation, water exchange, thermal conductivity of tissues and blood flow

What is the role of food and body reserves in thermoregulation?

They provide resources for internal heat production

How does muscle activity contribute to heat production?

Through exercise and shivering

What is an example of heat of fermentation?

Heat produced from rumen in cattle

How does body covering influence heat loss?

Through hair, color, and emissivity

What role does water exchange play in heat loss?

Through drinking and excretion

How does blood flow affect heat loss?

Through thermal conductivity of tissues and blood circulation

What is the relationship between body surface area and heat loss?

Body surface area influences the amount of heat that can be lost to the environment

What is the significance of moisture evaporation in heat loss?

It occurs from both skin and respiratory surfaces

How does air movement affect heat transfer?

It influences the rate of heat loss through convection and evaporation

What is a poikilotherm?

An organism that adapts to its environment with fluctuating body temperature

What is a homeotherm?

A warm-blooded organism with a constant body temperature

What are three factors affecting heat production?

Feed intake, muscular activity, and size

What are three methods of non-evaporative heat transfer?

Convection, conduction, and radiation

What is the relationship between body size and metabolic rate in animals?

Bigger animals tend to have lower metabolic rates

What happens to peripheral blood flow in cold temperatures?

Arterioles constrict, reducing capillary blood flow

What happens to peripheral blood flow in hot temperatures?

Arterioles dilate, increasing capillary blood flow

What is the thermoneutral zone?

The temperature range where a homeotherm can regulate body temperature with minimal energy cost

What are two behavioral mechanisms animals use to cool down?

Seeking shade and wallowing

What are two behavioral mechanisms animals use to stay warm?

Huddling and seeking shelter from wind and rain

What is brown adipose tissue important for?

Thermoregulation in neonates

What is hyperthermia?

A condition where heat production exceeds the ability to lose heat

What is hypothermia?

A condition where heat loss exceeds the capacity for heat production

What physical factor affects heat exchange between an animal and the environment?

Insulation

What behavioral factor affects heat exchange between an animal and the environment?

Burrowing

What is non-shivering thermogenesis?

A method of heat production not involving muscle contraction

What is the purpose of piloerection?

To increase insulation and reduce heat loss

How do chameleons change color?

Using photonic crystals in their skin

What is the difference between precocial and altricial species in terms of thermoregulation?

Precocial species are more developed at birth and better at regulating temperature

What is malignant hyperthermia?

A condition that can cause excessive heat production