Thermoregulation and Organism Adaptations

Vocabulary flashcards covering core body temperature regulation, thermal conditions, modes of heat transfer, and anatomical, physiological, and behavioural adaptations.

What is thermoregulation?

The process of maintaining a relatively constant core body temperature around $37\,^\circ\text{C}$.

What is the primary goal of thermoregulation in organisms?

To maintain optimum enzyme activity so metabolic reactions like respiration occur fast enough to sustain life.

At what core body temperature threshold does hyperthermia occur?

When core body temperature rises above $40\,^\circ\text{C}$.

What are the main symptoms of hyperthermia?

Fast breathing, confusion, fainting, pale skin, and coma.

At what core body temperature threshold does hypothermia occur?

When core body temperature drops below $35\,^\circ\text{C}$.

What are the main symptoms of hypothermia?

Shivering, pale skin, confusion, coma, and fast breathing.

How does positive feedback operate during hypothermia?

Lower core temperature reduces kinetic energy and enzyme activity, decreasing respiration and metabolic heat production, which causes body temperature to drop further.

What treatments can be used to raise core body temperature during hypothermia?

Using a warm dry bath, moving to a warm room, removing wet clothes, applying warm compresses, and offering warm non-alcoholic drinks.

What type of reaction releases heat energy within an organism?

Exothermic reactions, such as shivering.

How does latent heat of evaporation cool an organism?

Thermal energy is transferred away from the organism as water evaporates, such as during sweating.

What is radiation in the context of heat transfer?

Heat transfer via electromagnetic wave transmission, such as solar radiation from the sun.

What is convection in the context of heat transfer?

Heating and cooling processes involving fluid or air currents, such as heat rising upwards.

What is conduction in the context of heat transfer?

Heat transfer occurring by molecular collision through direct physical contact with surroundings.

What are the main ways an organism gains thermal energy?

Cell respiration waste heat, and conduction, convection, or radiation from surroundings.

What are the main ways an organism loses thermal energy?

Water evaporation, and conduction, convection, or radiation to surroundings.

What defines an ectotherm?

An organism that relies on external surroundings and behavioural responses to control core body temperature.

Which major animal groups are classified as ectotherms?

Invertebrates, amphibians, fish, and reptiles.

Why do aquatic ectotherms not need to thermoregulate?

Because the high specific heat capacity of water requires large energy changes per $1\,^\circ\text{C}$, preventing drastic temperature changes.

Why must land ectotherms actively thermoregulate?

Because land environments experience drastic temperature changes.

What is a behavioural adaptation?

An action performed by an organism to aid survival or reproduction, such as climbing high in trees to bask.

What is an anatomical adaptation?

A physical or structural feature of an organism's body, such as fur on the soles of feet for snow walking.

What is a physiological adaptation?

An internal process or chemical reaction within an organism, such as slowing down metabolic rate in winter.