Thermoregulation Flashcards
(11 cards)
What is homeostasis and why is it important?
Homeostasis is the regulation of an organism’s internal environment to maintain stable conditions essential for cell function. It prevents damage from external changes. Examples: blood glucose control, osmoregulation.
What is an endotherm? Give an example.
An endotherm maintains a constant internal body temperature through metabolic reactions, regardless of external temperature.
Example: Dog or human.
How is body temperature monitored and regulated?
Hypothalamus monitors core temperature.
Skin detects external temperature.
If too hot → activates heat loss center.
If too cold → activates heat gain center.
What is negative feedback in thermoregulation?
It’s a corrective mechanism that detects temperature changes and reverses them to maintain a set point. It involves:
- Thermoreceptors detect change → send sensory signals.
- Hypothalamus processes and sends motor signals.
- Effectors (like skin) produce a response (e.g., sweating or shivering).
How do endotherms regulate temperature?
By adjusting their metabolic rate, which increases internal heat through chemical reactions.
How do ectotherms regulate their temperature?
They rely on external environmental temperatures (e.g., basking in sun or hiding in shade).
List warming strategies used by animals.
Vasoconstriction: Reduces blood flow to skin.
Piloerection: Hair/feathers stand up to trap air.
Shivering: Muscle movement generates heat.
Brown adipose tissue (BAT): Burns lipids to produce heat.
Behavioral: Curling up, moving to warm places.
List cooling strategies used by animals.
Vasodilation: Brings more blood to skin.
Pilorelaxation: Hair/feathers flatten.
Sweating: Evaporation removes heat.
Panting and gular fluttering (in birds) for evaporative cooling.
Behavioral: Seeking shade, reducing movement.
Reduced metabolic rate: Lower heat production.
What is counter-current heat exchange and why is it useful?
Warm arterial blood transfers heat to returning cool venous blood. This conserves body heat and is especially helpful in extremities (e.g., limbs of arctic animals).
What is hypothermia and its symptoms?
Hypothermia = body temp too low.
Mild: Weakness, shivering
Moderate: Stiffness, low BP
Severe: Coma, slowed heartbeat, death
What is hyperthermia and its symptoms?
Hyperthermia = body temp too high.
Fever hyperthermia: From infection/inflammation
Non-fever: From exercise or thyroid issues
Symptoms: Panting, red skin/gums, dehydration, confusion, collapse, organ failure, death
