Homeostasis

Created by

Olivia

Cards (64)

What is homeostasis?
The maintenance of a stable internal environment despite fluctuations in internal and external conditions
Why is homeostasis important?
For enzymes and cellular processes in the body
What is responsible for homeostasis?
The nervous system and hormones
What levels must be maintained in the body?
Temperature, blood sugar and water
What are hormones?
Chemical messenger produced in the endocrine glands
What do hormones do?
Travels to a target organ and binds which initiates a response
Which hormone controls blood glucose levels?
Insulin
What is glucose needed for in cells?
Respiration
Where is insulin produced?
Pancreas
What does insulin do?
It regulates glucose levels in the blood
What processes does insulin carry out?
Causes an increase in uptake of glucose and converts glucose into glycogen for storage
What does glucagon do?
Causes the breakdown of glycogen into glucose which releases it back into the blood
What is glucagon?
A hormone that works when blood sugar falls
What is insulin?
A hormone that works when blood sugar rises
How is homeostatic control achieved?
Using negative feedback
What does negative feedback do when something rises?
The control systems reduce it again
What does negative feedback do when something falls?
Control systems raise it again
What is an example of negative feedback?
The control of blood glucose
When will blood glucose naturally increase?
After eating
When does blood glucose naturally fall?
After exercise
How is Type 1 diabetes caused?
When the pancreas doesn’t produce enough insulin
How is Type 2 diabetes caused?
When a person develops insulin resistance (links to obesity)
What is the treatment for Type 1 diabetes?
Insulin injections, managing diet and testing glucose levels
What is the treatment for Type 2 diabetes?
Managing diet, regular exercise and medication
Why is it important to maintain body temperature?
As the body’s enzymes work best at 37C
What is diabetes?
A condition where control of blood glucose stops working
What are the features of the structure of the skin?
sweat
sweat pore
sweat duct
sweat gland
blood capillaries
hair erector muscle
hair
What is this a diagram of?
The skin
What does deviations from optimum temperature do?
Decreases reactions
What is the main organ responsible for controlling body temperature?
Skin
What do hairs do when we are too warm?
They lie flat
Why do hairs lie flat when we’re too hot?
As hair traps air which is an insulator
What do hairs do when we’re too cold?
They stand up
Why do hairs stand up when we’re too cold? 
The hairs trap air which is an insulator and heats us up
Why do we sweat when we‘re too hot?
As it releases heat energy when it’s used to evaporate sweat
What is vasoconstriction?
A response to being too cold
What happens in vasoconstriction?
Narrowing blood vessels at the skins surface to reduce heat loss at the surface of the skin
What is vasodilation?
A response to being too hot
What happens in vasodilation?
Widening the blood vessels at the skins surface to increase heat loss
What response have plants developed?
Tropisms