Nervous System and Endocrine System Flashcards
(11 cards)
What is the nervous system?
Specialised network of cells in the human body and is our primary internal communication system.
It’ is divided in into two systems; the central nervous system (CNS) and the peripheral nervous system (PNS).
Functions of nervous system.
To collect, process and respond to information in the environment.
To co-ordinate the working of different organs and cells in the body.
What does the central nervous system do?
Made up of the brain and spinal chord.
Brain is centre of all conscious awareness. Cerebral cortex separates humans from animals in terms of intelligence.
Spinal chord is an extension of the brain and is responsible for reflex actions.
Passes messages to and from brain and connects nerves to PNS.
What does the Peripheral nervous system do?
Transmits messages via millions of neurons to and from CNS.
Sub-divided into Autonomic nervous system (ANS) and somatic nervous system (SNS).
What is the autonomic nervous system responsible for?
It transmits info to and from internal body organs.
It governs vital functions in the body such as breathing, heart rate, digestion, sexual arousal and stress responses.
What is the somatic nervous system responsible for?
Transmits info from receptor cells in sense organs to the CNS.
Controls muscle movement and receives info from sensory receptors.
What is the endocrine system?
Works alongside the nervous system to control vital functions in the body.
It instructs glands to release hormones directly into the bloodstream.
These hormones are carried towards target organs in the body.
What is the main endocrine gland and what are its functions?
The main endocrine gland is the pituitary gland, located in the brain, which acts as the master gland as it controls the release of hormones from all other endocrine glands in the body.
What is the fight or flight response in the endocrine system?
The way an animal responds when stressed. The body becomes psychologically aroused in readiness to fight an aggressor, or in some cases, flee.
How does the fight or flight response work?
The endocrine and ANS work together during a stressful event.
The hypothalamus triggers activity in the sympathetic branch of the ANS.
The ANS changes from parasympathetic state (resting) to the arouse sympathetic state.
Stress hormone adrenaline is released from adrenal gland into bloodstream.
Adrenaline increases heart rate which creates physiological changes in the body necessary for fight or flight response.
Happens automatically from detection of threat.
Parasympathetic nervous system returns body to resting state.
What are the changes associated with the sympathetic response.
Sympathetic - increases heart rate Para - decreases heart rate Symp-increases breathing rate Para- decreases breathing rate Symp - dilates pupils Para- constricts pupils
