The Human Brain Flashcards
What are the two main classes of cells that are the constituents of the nervous system- both central and periphery?
Neurons and glial cells
What is the cell body of a neuron known as?
Soma
What parts are all neurones composed of?
Dendrites A soma (cell body where the nucleus is present) Axon (only ever one of these) Axon Terminals
What do dendrites do?
Send electrical impulse to the soma (cell body)
What does the axon do?
Send electrical impulses away from the soma (cell body).
What does Glial mean?
Greek for Glue
What do glial cells do?
Play a supporting role for neurones
What does oligo mean?
It means few
What is an oligodendrocyte and what does it do?
Its a glial cell with few branches , however, the branches it does have wrap repeatedly around axons to form myelin sheaths. This cell is responsible for myelinating axons within the central nervous system.
What is the function of myelin?
It increases the speed and reliability of impulse conduction
Do oligodendrocytes myelinate neurones in the PNS?
NO myelination in the peripheral nervous sytem is done by Schwann cells
What is the difference between Oligodendrocytes and Schwaan cells?
Oligodendrocytes myelinate neurones in the CNS, whereas, Schwaan cells myelinate neurones in the PNS (periphery nerous system).
What type of cell is astrocyte or ‘star cell’?
It’s a type of glial cell. It gets it’s name as it has many processes.
What main roles do astrocytes play?
Mainly in mechanical support for neurones and their axons. A role in maintanence of the blood brain barrier in CNS. ( The have end-feet (exactly what you think it is) that wrap around the capillaries maintaining structural integrity).
What does the Central Nervous sytem comprise of?
Brain and spinal cord
What does the Peripheral nervous sytem comprise of?
Sensory and motor neurones (involunatry autonomic nervous system).
What does the human brain do for us?
Acquire knowledge (from perecption) Storing Information (as memory) Controlling Motor Behaviour Elemental movements (e.g. respiration, heart rate) Complex voluntary/‘willed’ actions (e.g, grasping) Crowning Achievement: Language & Communication What it does for us, collectively
Aprroximately how many neurones does the brain contain?
100 US billion (x10 more than the number of people on this earth).
Is bigger better when it comes to brain size?
Yes when compared to other animals scaled up.
Why is the brain very complicated?
Many different parts All with different names (sometimes several names) Each with a different, specialized function Specific brain regions interconnected by different specialized, axon pathways
What is functional specialisation in regards to the brain?
Functional specialization suggests that different areas in the brain are specialized for different functions.
When we split the brain in half laterally what do we refer to each section as?
A Hemisphere
What are the three major divisions of each hemisphere?
Cerebrum (largest) Cerebellum Brainstem (smallest)
Which of the three major divisions of each hemisphere is the biggest?
Cerebrum
Which of the three major divisons of each hemisphere is the smallest?
Brainstem
What is the brainstem directly attached to?
The spinal cord
What are the two main parts of the cerebrum?
Telencephalon (forebrain)
Diencephalon ( between brain)
What are the subdivisions of the Telencephalon?
–Cerebral Cortex: conscious sensation/perception, voluntary movements & higher cognitive (e.g., language) functions
–Basal Ganglia: movement planning & control
What are the subdivisions of the Diencephalon?
–Thalamus: various nuclei (related to the cerebral cortex)
–Hypothalamus: various nuclei for regulating appetites & endocrine functions (via connections with the pituitary gland)
–Epithalamus: pineal gland, secretes melatonin, regulates circadian rhythms
Which subdivision of the Telencephalon is the largest?
The cerebral cortex
What is the cerebral cortex responsible for?
Conscious sensation/perception, voluntary movements & higher cognitive functions (e.g., language, memory)