week 1

Question 1

Discuss the anatomical features of the spinal cord

Answer 1

Component of the CNS

built up of 3 layers (in to out) pia mater, arachnoid mater, and dura mater (these are the spinal cord meningies)
Pia is thin is just there to separate from the brain, arachnoid is Web like structure to allow the flow of cfs and dura mater is harder).
The adult spinal cord is approx 45cm long and max 14mm wide (it ends betwen vertebrae L1-L2)
It is comprised of an outer layer of white matter and an inner layer of gray matter.
It is divided into 31 segements each of which give rise to a pair of spinal nerves. 8 cervical, 12 thoraxix, 5 lumbar, 5 sacral and 1 coccygeal.
white matter is responsible for conducting, processing and sending nerve signals up the spinal cord (dendrites) (assending and decending pathways), gray matter is built up of neuron cell bodies, glial cells and capillaries.

Question 2

name the four main regions of the brain and describe their function

Answer 2

frontal lobe: higher cognitive functions: emotional pxression, problem-solving, memory, speaking (brocas) judgement, sexual behavours (located on the front of the brain)
Parietal: Primary sensory awareness (warmth, cold, touch, pain), spatial information, and solve math probems (located centre of brain, behind frontal, above temporal)
Temporal: processing auditary information (understanding language - wernicke’s), managing emotions, storing and retriving memories (middle of brain below the parietal)
Occipital: visual processing (located at the back)

Question 3

List the divisions of the ANS an the general functions of each

Answer 3

CNS and PNS (give quick description)
ANS is in the PNS (other is Somatic(voluntary)
the autonomic nervous system is a component of the PNS that regulates involuntary processes (HR, BP, respiration, digestion, sexual arrousal) and consists of 3 distinct divisions:
Sympathetic, parasympathetic and enteric

Sympathetic - known as fight or flight is the go button, it makes HR increase etc.
Parasympathetic - known as rest and digest, is the stop button, it decreases HR ect.
Enteric- has control of the gastrointestinal tract

Question 4

describe the innervation patterns of the sympathetic and parasympathetic divisions of the ANS

Answer 4

sympathetic innervation is supplied by spinal segments T1-L3 of the spinal cord. They are fight or flight (HR, BP, blood vessels, etc.) it uses norepinephrine as the primary neurotransmitters. - they originate from the spinal cord then synapse with a ganglionic neuron -> post ganglion fibre -> either acts directly on target tissue or works through the circulatory system transmit signal.

Parasympathetic innervation is mostly cranial nerves that interact directly with the target organ and mainly use ACh as its neurotransmitter.

Question 5

describe the types of sympathetic and parasympathetic receptors and their associated neurotransmitters

Answer 5

parasympathetic NS uses ACh - and ACh attatches to two different types of receptors: muscarnic and nicotinic cholinergic receptors.
nictonic - rapid nueral and neuromuscular transmission - N1 and N2
Muscarnic - slower transmission - excitatory or inhibitory - smooth muscle and cardiac conduction system - M1 - M5

Sympathetic - adrenaline and noradrenaline - A1, A2, B1, B2