CNS Flashcards
Name and describe the components of the diencephalon.
Thalamus:
- Major relay for sensory impulses
- Memory processing
Hypothalamus- Body’s homeostasis:
- ANS visceral functions & emotional response
- Regulates: body temperature, food intake, water balance & thirst
- Olfactory relay station
Epithalamus:
- Pineal gland
- Melatonin– helps regulate sleep-wake cycles
Name and locate the ventricles of the brain.
R & L lateral ventricles, 3rd ventricle and 4th ventricle.
R & L lateral ventricles are located within their respective hemispheres of the cerebrum.
3rd V: In btw right and left thalamus
4th V: Lies within the brainstem, at the junction btw pons and medulla oblongata
Difference btw grey and white matter.
Grey:
- Short non-myelinated neurons
White:
- Mostly myelinated axons
Function of internal capsule
V. IMPT NERVES
if internal capsule is damaged, there could be damage to the sensory & motor nerves
List the functional areas of the cerebral cortex.
Sensory Areas
- Primary somatosensory cortex
- Primary visual area
- Primary auditory cortex
- Auditory association area
- Wernicke’s Area
Motor Areas
- Primary motor complex
- Premotor cortex
- Broca’s area
- Prefrontal cortex
In what ways are the cerebellum and the cerebrum similar? In what ways are they different?
- Both have a thin outer cortex of gray matter, internal white matter, and deep gray matter nuclei.
- Both have body maps (homunculi) and large fiber tracts connecting them to the brain stem.
- Both receive sensory input and influence motor output.
- Cerebellum is almost entirely concerned with motor output, whereas the cerebrum has much broader responsibilities.
- Cerebral hemisphere controls the opposite side of the body, a cerebellar hemisphere controls the same side of the body.
Function of nervous tissue
Transmit electrical signals from sensory receptors and to effectors (muscles and glands) which control their activity.
Explain importance of myelin sheath and describe how it is formed in the central and peripheral nervous systems.
Myelin protects and electrically insulates fibers, and increases transmission speed of nerve impulses.
In PNS: the sheaths are formed by Schwann cells
In CNS: sheaths are formed by oligodendrocytes
Classify neurons by structure and by function.
- Unipolar
- 2 branches
- Mainly in the PNS
- Most are sensory
- Function: conduct impulses along afferent pathways to the CNS for interpretation - Bipolar
- 1 axon + 1 dendrite
- Rare: only in special locations like eye, olfactory mucosa,etc
- ALL are sensory
- Function: involved in the transmission of special senses - Multipolar
- 1 axon + mainly dendrites
- Most abundant and in CNS
- Most are interneurons
- Function: account for the extensive interconnectivity allowing higher cognitive processes to take place
Which type of neuroglia controls the extracellular fluid around the neuron cells bodies in the CNS and in PNS?
CNS: Astrocytes
PNS: Satellite cells
Which types of neuroglia form insulating coverings called myelin sheaths?
CNS: Oligodendrocytes
PNS: Schwann cells
Name the cranial nerve(s) most involved in each of the following: moving your eyeball; sticking out your tongue; controlling your heart rate & digestive activity; shrugging your shoulders
The oculomotor (III), trochlear (IV), and abducens (VI) nerves control eye movements.
Sticking out your tongue involves the hypoglossal nerve (XII). The vagus nerve (X) influences heart rate and digestive activity.
The accessory nerve (XI) innervates the trapezius muscle, which is involved in shoulder shrugging.
What is CSF? Where is it produced? What are its functions?
CSF is a clear fluid that surrounds the brain and spinal cord.
Produced by the choroid plexus.
It cushions the brain and spinal cord from injury and also serves as a nutrient delivery and waste removal system for the brain.
