The nervous system and the endocrine system Flashcards
What is the nervous system?
Nervous system and endocrine system
Specialised network of cells in human body and primary communication system
Based on electrical and chemical signals
What are the main functions of the nervous system?
Nervous system and endocrine system
- To collect, process and respond to information in the environment
- To co-ordinate the working of diff organs and cells in the body
What two subsystems is the nervous system divided into?
Nervous system and endocrine system
- Central nervous system (CNS)
- Peripheral nervous system (PNS)
What is the CNS made up of?
Nervous system and endocrine system
- Brain
- Spinal cord
The brain
Nervous system and endocrine system
Centre of all conscious awareness
Cerebral cortex (outer layer) 3mm thick - covers brain like orange peel
Only found in mammals
The spinal cord
Nervous system and endocrine system
Extension of the brain
Passes messages to and from brain and connects nerves to PNS
Responsible for reflex actions
Role of the PNS
Nervous system and endocrine system
Transmits messages via millions of neurons to and from the CNS
What is the PNS subdivied into?
Nervous system and endocrine system
- Autonomic nervous system (ANS) - governs vital functions in body such as breathing, heart rate, etc
- Somatic nervous system (SNS) - governs muscle movement and recieves infor from sensory receptors
What is the endocrine system?
Nervous system and endocrine system
Intructs glands to release hormones directly into bloodstream
These are carried to target organs in body
Communicates via chemicals
What is a gland?
Nervous system and endocrine system
An organ in the body that synthesises substances such as hormones
Example: Thyroid gland produces thyroxine
What are the names of the glands in the human body?
Nervous system and endocrine system
- Hypothalamus
- Pituitary - master gland
- Thyroid
- Parathyroid
- Andrenal
- Pancreas
- Ovaries (female)
- Testes (male)
Fight or Flight
Nervous system and endocrine system
When stressor is percieved, hypothalamus activates pituitary gland which triggers sympathetic branch of ANS
ANS changes from parasympathetic (resting) state to physiologically aroused sympathetic state
Fight or Flight: Adrenaline
Nervous system and endocrine system
Released from adrenal gland (near kidney) into bloodstream
Andrenaline triggers physiological changes in body which creates physiological arousal necessary for fight or flight response
Fight or Flight: Immediate and automatic
Nervous system and endocrine system
Happens as soon as threat is detected
Acute response and automatic reaction
Fight or Flight: Parasympathetic action
Nervous system and endocrine system
Once threat has passed, parasympathetic NS returns body to resting state
Parasymp branch of ANS works in opposition to symp branch - actions are antagonistic
Rest and digest response
