YR11 - SAC: Chapter 4 Review Flashcards
The ‘central nervous system’ (CNS)
The brain and the spinal cord
Integrating sensory information
Coordinating both conscious and unconscious activity
The ‘peripheral nervous system’ (PNS)
The somatic and autonomic systems
The peripheral nervous system is made up of all those nerves that lie outside the Central Nervous System (brain and spinal cord).
The role of the spinal cord is…
The transmission of sensory information from the peripheral nervous system to the brain
The transmission of information from the brain to the peripheral nervous system
Describe the ‘somatic nervous system’ (SNS)
The somatic nervous system is made up of nerves that connect to voluntary skeletal muscles and to sensory receptors.
What is a nerve?
A nerve consists of a bundle of neurons
Define ‘affrent nerves’
Carry information inward to the central system from the periphery of the body.
Define ‘efferent nerves’
Carry information outward from the central nervous system
What are ‘sensory’ neurons?
An afferent neuron,
Transmit neural messages from the sensory organs to the brain
What are the motor’ neurons?
An efferent neuron,
Transmit neural messages from the brain to various areas of the body including muscles, internal organs and glands.
Enables bodily movements,
Define ‘interneurons’
Connect between motor and sensory neurons.
Exist only in the central nervous system (brain and spinal cord)
Have a single dendrite coming into the cell body and a single axon leaving the cell body.
Glial cells functions…
To surround neurons and hold them in place
To supply nourishment and oxygen to neurons
To remove dead neurons
Describe the ‘automatic nervous system’ (ANS)
The autonomic nervous system (ANS) is made up of a network of neurons that connects the CNS to all the body’s internal (smooth) muscles and organs (such as the heart, stomach and liver), blood vessels and glands (including sweat, salivary and adrenal).
It controls automatic, involuntary, visceral functions.
Describe the ‘parasympathetic nervous system’
The parasympathetic branch of the ANS keeps the systems of the body functioning efficiently helps to maintain a constant internal body environment (homeostasis).
Describe the ‘sympathetic nervous system’
The sympathetic nervous system prepares your body for physical and mental activity. It makes your heart beat faster and stronger, opens your airways so you can breathe more easily, and inhibits digestion.
The ‘fight or flight’ response…
When activated by the SNS the medulla releases adrenaline into the bloodstream. Responses include an increase in heart rate, blood pressure and cardiac output, increased pupil size and metabolic changes such as fat and glycogen into the bloodstream.
