Flashcards in The Nervous System Deck (23):
What are the two main features of the nervous system?
- to collect, process and respond to info in the environment
- to coordinate the working of different organs and cells in the body
The nervous system is divided into...?
The CNS and PNS
What is the CNS?
Made up of the brain and spinal cord.
The brain is part of the CNS. What is its function?
The brain is the centre of all conscious awareness.
What aspect of out CNS distinguishes our higher mental function than those of animals?
The outer layer of the brain - cerebral cortex.
The spinal cord is in the CNS. What is it?
Spinal cord is an extension of the brain
The spinal cord is in the CNS. What is its function?
It's responsible for reflex actions.
And passes messages to and from the brain, and connects nerves to the PNS.
What is the function of the PNS?
To transmit messages, via millions of neurons to and from the nervous system.
What is the PNS sub-divided into?
The autonomic nervous system and somatic nervous system.
The ANS is a subdivision of the PNS. What is its function?
The ANS governs vital functions in the body eg breathing, heart rate digestion.
The SNS is a sub-division of the PNS. What is its function?
The SNS controls muscle movement, and receives info from sensory receptors.
What is the endocrine system?
The endocrine system works alongside the nervous system to control vital functions in the body through the actions of hormones.
What is the major difference between the nervous and endocrine system?
The endocrine system works much more slowly than the nervous system, but has widespread and powerful effects.
Glands are involved in the endocrine system. What are they?
Organs in the body that produce hormones.
What is the major endocrine gland?
The pituitary gland (brain).
Called the 'master gland' as it controls the release of hormones from all other endocrine glands in the body.
Hormones are involved in the endocrine system. What are they?
Hormones are secreted in the bloodstream, and affect any cell in the body that has a receptor for that particular hormone.
Give an example of an important hormone in the endocrine system?
Thyroxine - produced by thyroid gland. Thus affects cells throughout the body which increases metabolic rate. This in turn affects growth rates.
When do the endocrine system and ANS work together?
In the FoF response.
Outline the porches of the FoF response.
1. A stressor is perceived, so the hypothalamus triggers activity in the sympathetic branch of the ANS. This thus changes from normal resting state (parasympathetic) to physically aroused sympathetic state.
2. Adrenaline is released from adrenal medulla into bloodstream.
3. This hormone triggers physiological changes in target organs in the body. Eg causes increased HR, dilated pupils.
4. Once the threat has passed, the PNS returns the body to its resting state ('rest and digest').
What is triggered when a stressor is perceived in the FoF response?
Where is adrenaline released from the in the FoF response?
The adrenal medulla.
Give examples of the sympathetic state in the FoF response?
Increased HR, increased breathing rate, dilated pupils, inhibition of digestion, inhibition of saliva production, contracts rectum.