Maintaining an Internal Balance Flashcards
Unit 4 Lesson 1 (14 cards)
Define homeostasis and dynamic equilibrium
Homeostasis is the body’s ability to maintain a stable internal environment.
Dynamic equilibrium refers to the small, continuous adjustments the body makes to maintain this stability.
How are homeostasis and dynamic equilibrium connected?
Dynamic equilibrium is how homeostasis is maintained — the body constantly adjusts internal conditions to stay balanced.
How does the body maintain homeostasis?
The body uses feedback systems (mainly negative feedback) to detect changes and trigger responses that return internal conditions to normal.
Give an example of how the body maintains homeostasis.
When blood sugar rises after eating, the pancreas releases insulin to lower it back to a normal level.
Describe the difference between negative and positive feedback loops.
Negative feedback reverses a change to return to normal (e.g., cooling down when hot).
Positive feedback amplifies a change to speed up a process (e.g., contractions during childbirth).
What type of feedback loop is most used in the body to maintain homeostasis?
Negative feedback — because it works to reverse changes and bring the body back to its normal state.
Why is negative feedback more commonly used than positive feedback to maintain homeostasis?
Because it keeps internal conditions stable by correcting changes from the normal state.
What is thermoregulation?
Thermoregulation is the process by which animals maintain a stable internal body temperature.
How do animals thermoregulate?
They use behavioural methods (e.g., basking, seeking shade) and physiological responses (e.g., sweating, shivering, changing blood flow).
Compare the two types of animal thermoregulation.
Ectotherms rely on external sources for heat (e.g., reptiles), use less energy.
Endotherms produce their own heat internally (e.g., mammals), use more energy to stay warm.
What is the hypothalamus?
A brain region that monitors and regulates key body conditions like temperature, hunger, and thirst. It acts as the body’s thermostat.
Why is the hypothalamus important for homeostasis?
It detects internal changes and sends signals to organs and glands to correct imbalances (like shivering when cold).
How does our body respond to a rise in core temperature?
Blood vessels widen, sweat glands activate, and the body cools down through evaporation.
How does our body respond to a drop in core temperature?
Blood vessels narrow/ shrink, muscles shiver to generate heat, and metabolism may increase.
