11.2 The CNS Flashcards
The CNS is composed of two types of nervous tissue:
- Grey matter
2. White matter
Grey Matter + where it is found
- Grey because it contains mostly cell bodies, dendrites, and short, unmyelinated axons (Nerve fibres)
- Found on the outside areas of the brain and H shaped core of the spinal cord
White matter
Contains myelinated axons that forms the inner region of brain and outer of spinal cord
Spinal cord (3)
- vital communication link between the brain and the PNS
- within the spinal cord, sensory nerves carry messages from the body to the brain for interpretation and motor nerves relay messages from the brain to the effectors
- primary reflex centre, coordinating rapidly incoming and outgoing neural information
Outside of spinal cord:
- white matter
- myelinated nerve fibres
Inside of spinal cord
- Butterfly shaped core of grey matter
- unmyelinated neurons as well as the cell bodies and dendrite of many spinal neurons
What are the delicate tissues of the spinal cord protected by?
- Cerebrospinal fluid, soft tissue layers and the spinal column ( a series of backbones vertebrae)
Menings
three layers of tough elastic tissue within the skull and spinal column, directly enclose the brain and spinal cord
Names for the forebrain:
- cerebrum cortex or cerebrum
- Largest part of the brain
What does the right hemisphere of the forebrain do?
- creative and abstract
What does the left hemisphere of the forebrain do?
Analytical and concrete
Corpus callosum (3)
- Connection between the two hemisphere
- sends messages from one cerebral hemisphere to the other, telling each half of he brain what the other half is doing
- white matter
Four lobes of the cerebrum
Frontal,
Parietal
temperal
occipital
Cerebellum
fine motor
posture
balance
Medulla Oblongata (3) with ex:
connects brain with spinal cord
Autonomic, involuntary responses
heart rate, breathing, blood pressure
Pons
Sleep
Midbrain (2)
relays visual and auditory information between areas of the hindbrain and forebrain
plays important roll in eye movement
Thamalamus
Connection between various parts of the brain
Blood-brain barrier
The meanings protect the CNS by preventing direct circulation of blood through the cells of the brain and spinal cord.
- protects the brain and supplies the brain with nutrients and oxygen. Lipid soluble substances are able to pass directly.
cerebrospinal fluid
- circulates throughout the spaces to ventricles within the brain and spinal cord
- acts as shock absorber for brain and transport hormones, white blood and nutrients across the blood brain barrier for cells of the spinal cord and brain
Occipital Lobe
- receive and analyze visual info
- needed for recognition of what is being seen
Temperal lobe+ area
Auditory reception hearing
-Includes wenicke’s area (Language comprehension)
Parietal lobe
Somatosensory functions (interpret body sensations): touch/taste
- processes info about body position
Frontal lobe (5)+ area
Conscious thought intelligence memory personality voluntary muscle movements Bronca's area (Language production) *Translate thoughts into speech)
Hypothalamus
homeostatsis+manages hormones
ex: regulates blood sugar
heart rate
blood pressure
