The Nervous System

What is the nervous system?

Netw of cells in our body that uses electrical & chem signals to communic internally

What are the two main functions of the nervous system?

• To collect, process & respond to info in the environ

• to co-ordinate working of diff organs + cells in body

What are the two subsystems of the nervous system?

Central Nervous System (CNS) and Peripheral Nervous System (PNS)

CNS (central nervous system)

• Processes info from senses + uses it to co-ordinate everything from voluntary actions like walking → automatic func like breathing + heart rate

• consists of brain + spinal cord: brain has outer layer called cerebral cortex & is more highly developed in hum than anim

• has 2 hemispheres

• spinal cord: passes msgs to + from brain + connects nerves to PNS

• it ctrls reflex actions

PNS (peripheral nervous system)

• transmits msgs via millions of neurons to & from CNS

• consists of: ANS & SNS

What does the autonomic nervous system do?

• Transmits info to + from internal bodily organs

• Ctrls vital func e.g breathing, heart rate, digestion, sexual arousal, stress resp

• Consists of sympathetic nerv syst + parasympathetic nerv syst

• Sympathetic nerv syst works alongside endocr syst to bring ab physiological arousal + prep body for f/f resp during times of acute stress

• Parasympathetic nerv syst works alongside the endocr syst to relax body + return body to its 'normal' resting state in the rest & digest resp

What does the somatic nervous system do?

transmits info from sense organs to CNS and info from CNS to effectors such as muscles