Lesson 1 - The Nervous System Flashcards
The Central Nervous System (CNS)
Consists of the brain and spinal cord
Controls behaviour and regulation of the body’s physiological processes
Brain must be able to receive information from sensory receptors and be able to send messages to the muscles and glands of the body in response
The Central Nervous System
The Brain
Cerebrum - 4 lobes, split down the middle into 2 halves; left and right hemisphere
Cerebellum - Responsible for motor skills, balance and coordinating the muscles that allow precise movements
Diencephalon - Contains thalamus (regulates consciousness, sleep and alertness) and hypothalamus (regulates body temperature, stress response and hunger and thirst)
Brain Stem - Regulates breathing and heart rate
The Central Nervous System
The Spinal Cord
Relay information between brain and body
Allows brain to monitor and regulate bodily processes
Connected to different parts of the body by pairs of spinal nerves, which connect to specific muscles and glands
If damaged body areas connected to it by nerves below the damage will be cut off and stop functioning
The Peripheral Nervous System (PNS)
Consists of the nervous system throughout the rest of the body - no brain or spinal cord
Transmits messages via neurons (nerve cells) to and from the CNS
Has 2 divisions; the somatic nervous system and the autonomic nervous system
The Peripheral Nervous System
The Somatic Nervous System
Controls voluntary movements and is under conscious control
Connects with senses with the CNS and has sensory pathways and motor pathways
Controls skeletal muscles
Controlled by the motor cortex
The Peripheral Nervous System
The Autonomic Nervous System
Involuntary
Only has motor pathways
Controls smooth muscles and the internal organs and glands
Controlled by the brain stem
Sympathetic Nervous System (SNS)
Parasympathetic Nervous System (PNS)
The Peripheral Nervous System
The Autonomic Nervous System
The Sympathetic Nervous System
Activated when a person is stressed
Heart rate and breathing increase
Digestion stops
Salivation reduces
Pupils dilated
Flow of blood is diverted from the surface on the skin
Fight or flight response
The Peripheral Nervous System
The Autonomic Nervous System
The Parasympathetic Nervous System
Activated when the body is relaxing and so conserving energy
Heart rate and breathing reduce
Digestion starts
Salivation increases
Pupils constrict
Nervous Systems Diagram
