Tissues 6 Flashcards
What are the four regions of the cerebral hemispheres?
Frontal, parietal, occipital and temporal.
What does the brainstem consist of?
Midbrain, pons and medulla (in descending order)
Where do all the cranial nerves originate form?
Brainstem
What is the function of the cerebellum?
Motor coordination, balance and posture
What is the most common type of neurone?
Multipolar
What are the three types of multipolar neurone?
Pyramidal, purkinje and golgi (later two are related to GABA neurones)
What are the four types of neurones?
Unipolar, pseudo-unipolar, bipolar and multipolar
What features do all neurones share?
- Soma (perikaryon)
- Axon
- Dendrites
What is the function of an astrocyte?
Structural cells, involved in repair and immune responses within the CNS. They are also involved in neurotransmitter release and reuptake.
Which is the most abundant cell in the CNS?
Astrocyte as they are able to proliferate
What is the function of oligodendrocytes?
Present in the CNS producing myelin. One oligodendrocyte can myelinate many axons.
What is the function of a Schwann cell?
The same as oligodendrocytes but in the PNS instead. One Schwann cell can only myelinate one axon section though.
What is a microglial cell?
Specialised cells similar to macrophages so have immune functions within the CNS.
What is the function of ependymal cells?
They are the epithelial cells of the CNS - they line the fluid-filled ventricles and regulate the production and movement of CSF.
What is saltatory conduction?
Mechanism that allows APs to spread along the axon by cable transmission, preventing AP spreading.
How do synapses work?
1) The AP opens voltage-gated Ca2+ channels that are concentrated at the end of pre-synaptic terminal
2) Ca2+ influx causes neurotransmitter release by binding to the vesicles, causing exocytosis
3) Activation of post-synaptic receptors
4) Neurotransmitters dissociates from receptor and is either recycled or broken down by enzymes in the synaptic cleft
What is the function of the pons?
Bridge between several important parts of nervous tissue and a source of several nerves serving the face, important in chewing, biting and swallowing.
What is the function of the medulla?
Autonomous actions such as breathing, swallowing and heart rate.
What is the function of the midbrain?
Relay system from auditory and visual centres.
What is the function of the parietal lobe?
Associated with complex behaviours such as vision, touch and spatial awareness.
What is the function of the temporal lobe?
Associated with perception, auditory processing and language production.
What is the function of the frontal lobe?
Reasoning, problem solving, speaking, remembering and emotions etc.
What is the function of the occipital lobe?
Visual processing.
