Nervous System and Homeostasis Flashcards
What is the function of the nervous system?
It enables organisms to react to their surroundings and coordinates behaviour
What are the two parts of the central nervous system?
Brain and Spinal Cord
Why are reflex actions described as rapid and automatic?
They do not involve the conscious part of the brain
Why are reflex actions important?
For survival and to prevent damage to the body
Give the pathway of a nervous response
Stimulus > receptor > coordinator > effector > response
Give the function of the cerebral cortex
Outer layer of the brain playing an important role in consciousness
Give the function of the medulla
Part of the brain above the spinal cord that controls the breathing and the heart rate
Give the function of the cerebellum
Part at the back of the brain involved in coordinating muscle activity
Why is it difficult to treat brain disorders?
Brain is very complex and delicate
What is a synapse?
Gap between two neurones, allowing impulses to cross
What is the function of neurones?
Carry electrical impulses around the body
What is homeostasis?
Maintenance of a constant internal environment
Give three internal conditions controlled by homeostasis
Body temperature
Blood Glucose concentration
Water levels
Give three things control systems include
Receptors
Coordination centres
Effectors
What is accommodation?
Process of changing the shape of the lens to focus on near/distant objects
Give two commons defects of the eyes
Myopia (short-sightedness)
Hyperopia (long-sightedness)
How can eye defects be treated?
Spectacle lenses, contact lenses, laser eye surgery, replacement lenses in the eye
Where is body temperature monitored and controlled?
Thermoregulatory centre in the brain
What happens if body temperature is too high?
Blood vessels dilate (vasodilation) and sweat is produced
What happens if body temperature is too low?
Blood vessels constrict (vasoconstriction), sweating stops and shivering takes place
