The CNS is composed of the brain and the spinal cord
The peripheral nervous system is made up from sensory neurones carrying impulses from the receptors to the CNS and motor neurons to move the skeletal muscles
Peripheral nervous system
Somatic nervous system
Deals with functions under conscious control like walking and speaking
Autonomic nervous system
Controls bodily functions like heart rate, these are controlled unconsciously
Made up of nerves cells inside the brain and emerge at various points down the spinal cord to reach effectors like cardiac muscle, smooth muscle and glands.
They stimulate nerve impulses to carry out homeostatic control.
Divided into the sympathetic and parasympathetic systems
Known to be antagonistic as they affect the same structure but have opposite effeccts.
The parasympathetic part is dominant at times of resting when heart rate is low, breathing rate is reduced and the blow flow to the muscles is reduced and increased to the digestive system and its muscles.
Known as the 'rest and digest' response, it calms the body down to conserve resources and energy.
The sympathetic is during times when the body is active causing an increased heart and breathing rate, perspiration and redistribution of blood to the muscles instead of the digestive system
Known as the 'fight of flight' when the body is preparing for action
Parts of the brain
Central Core
Contains the medulla which regulates the basic life processes of breathing, heart rate, arousal (being awake and aware fo the external environment) and sleep
Also contains the cerebellum which is responsible for control of balance, posture and movement
Limbic System
part of the brain involved with processing information for memories, regulating emotional states and influencing biological motivation like hunger
Cerebral coretex
Outer layer of the cerebrum
The cerebrum is divided into two cerebral hemispheres
The left side processes information from the right visual field and controls the right side of the body
The right side processes information from the left visual field and controls the left side of the body
The sides are connected by a bundle of nerves called the corpus callosum
Contains 3 types of functional areas: sensory, association and motor.
The sensory receives information as sensory impulses from the body's receptors
The association areas analyse and interpret these impulses to make sense of them and take decisions.
The motor areas receive information from the association area and carry out orders by sending motor impulses to the appropriate effectors