Nervous System Flashcards
(26 cards)
CNS
(central nervous system)
- is the main centre for the entire nervous system and is compromised of the brain and spinal cord
PNS
(Peripheral nervous system)
- refers to all the neurons that lead to and from the CNS
- it is divided into 2 groups
What groups is the PNS divided into?
- Somatic
- Autonomic
Somatic
- The nerves in this system relay information from the sensory receptors, to the CNS, then from the CNS to the skeletal muscles
- This process is usually voluntary
Autonomic
- Carries impulses from the CNS to the heart and other internal organs, and the body responds involuntary
What two ways is the autonomic system important?
- Sympathetic nervous system
- Parasympathetic nervous system
Sympathetic nervous system
Is most active when the body is under stress. When you are in a stressful situation, your body will respond with FIGHT or FLIGHT responses
Parasympathetic nervous system
Is most active when the body is at rest. After being in a stressful situation, the parasympathetic nervous system (PNS) will return the body back to normal working conditions.
When the sympathetic nervous system is in control…
- Dilated pupils
- inhibits flow of saliva
- accelerates heart beat
- dilated bronchi
- inhibits peristalsis and secretion
- converts glycogen to glucose
- inhibits bladder contraction
When the parasympathetic nervous system is in control…
- stimulates flow of saliva
- slows heart beat
- constricts bronchi
- stimulates peristalsis and secretion
- stimulates release of bile
- contracts bladder
Explain fight or flight responses:
your body gears up to control your organs in times of stress, & especially when your in a scary situation
Glycogen
Extra glucose stored as large molecules in the liver that can be used as energy later
Cerebellum
Is involved in the unconscious coordination of posture, reflexes, body movements, and voluntary motor skills
- LOCATED below and behind the cerebrum
Medulla Oblongata
Helps regulate breath, heart, & blood vessel function
LOCATION: sits at the base of the brainstem where it connects the brain with spinal cord
Pons
serves as a relay centre between neurons of the right left halves of the cerebellum, cerebrum, & rest of the brain
LOCATED: infront of the medulla oblongata in the brainstem
Midbrain
Processes information from sensory neurons in the eyes, ears, & nose. It relays visual & auditory information
LOCATED: above pons in brainstem
Cerebrum
Is the largest part of the brain and contains the centres for learning, memory, conscious, & language.
- it is divided into the right & left cerebral hemispheres
Thalamus
Consists of neurons that provide connections between different parts of the brain. These connections are mostly between the forebrain & hindbrain, & between areas of the sensory system & cerebellum
LOCATION: sits at the base of the forebrain
Hypothalamus
Regulates the body’s internal environment, by controlling the blood pressure, heart rate, body temp. & emotions
LOCATION: lies below the thalamus
Corpus Collosum
Sends messages from one hemisphere to another
Pituitary Gland
Produces critical hormones which control various bodily functions
Myelinated Neurones
Form white matter, which forms the inner region of the brain & outer area of the spinal cord
Unmyelinated Neurones
Form grey matter which is found around the outside of the brain & forms the H-shaped core of the spinal cord
Meninges
Protects the spinal cord & bony vertebrae, & brain with 3 layers of tissue
