Discuss the nervous system and the endocrine system.
The Nervous System The Nervous System (cont) The Endocrine System The Endocrine System
● Specialised network of ● Peripheral divided into somatic + ● Network of glands around body, ● Endocrine system regulated by
cells & primary autonomic. secretes hormones into feedback.
communicator. ● Brain receives info from sensory bloodstream. ● As levels of a hormones rise in
● Collects and processes receptors eg eyes and sends ● Works with NS to regulate the bloodstream, secretion of the
info from environment. messages to body’s muscles. physiological processes. hormone is reduced.
● Coordinates organs + ● Messages sent via spinal cord, ● Each gland produces different ● Results in stable concentrations
cells in the body. collection of nerve cells attached to hormones, regulate activity of of hormones circulating in the
● Divided into CNS + PNS. brain and run the length of the spinal cells or organs in the body. body.
● NS controls body’s column. ● Slower than nervous system, but ● Timing of secretion is crucial, too
physiological processes. more widespread and has more much/too little can result in
powerful effects. dysfunction of bodily systems
Peripheral Nervous System Peripheral Nervous System (PNS) Glands Hormones
● Transmits messages via ● SNS controls muscle movement and ● Glands are organs in body that ● Secreted into the bloodstream
millions of neurons, to receives information from sensory produce hormones. and affect any cell in the body
and from nervous system receptors. ● Major endocrine gland is the that has a receptor for that
● Divided into autonomic ● Relays info from CNS to other areas pituitary gland, located in the particular hormone.
+ somatic NS. of body using motor neurons. gland. ● Thyroxine produced by the
● ANS governs vital ● SNS also involved in reflex actions, ● Controls release of hormones thyroid gland affects cells in the
functions eg breathing, without involvement of CNS, allows from other endocrine glands in hearts + throughout the body,
digestion, heart rate. reflex to occur quickly. the body. increasing metabolic rate. Also
● Occurs unconsciously ● In ANS, para slows physiological affects growth rate.
otherwise digestion slow activity down, SympaNS, increases♡
Central Nervous System (CNS) Central Nervous System (cont) Fight or Flight Fight or flight (cont)
● Made up of brain & ● Spinal cord is extension of brain, is ● Endocrine + ANS work together ● Stress hormone adrenaline
spinal cord. responsible for reflex actions. in F&F response. When stressful released from adrenal medulla
● Brain is centre of ● Passes messages to and from the event occurs, hypothalamus into the bloodstream.
conscious awareness brain and connects nerves to the triggers activity in the sympaNS ● Adrenaline triggers physiological
● Cerebral cortex is outer PNS. in the ANS. changes in target organs,
layer, highly developed, ● Controls behaviour and regulation of ● ANS changes from normal increases heart rate, dilation of
distinguishes higher body’s physiological processes. resting state (para) to pupils, less saliva produced
mental function from physiologically aroused state ● ParaNS returns body to resting
other animals. (sympa) state. state (rest+digest) response
Describe the structure and function of neurons and synaptic transmission.