Lecture notes
PNS1 lecture notes with examples from book
- Module
- Physiology (BM4MAP)
- Institution
- Aston University, Birmingham (Aston)
PNS in depth notes with example of eye and pain pathway
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
Seller
Follow
Content preview
Afferent division of the PNSBrain and the spinal cord receive information about:
1. Internal environment= visceral stimuli.
2. External environment= sensory stimuli.
2 types of afferent divisions in the PNS
1. Sensory afferent e.g., vision, hearing, taste, and smell= conscious input
2. Visceral afferent e.g., blood pressure, heart rate= subconscious input.
Efferent division of the PNS
1. Somatic nervous systemcontrols skeletal muscles (voluntary control)
2. Autonomic nervous systemcontrols sympathetic and parasympathetic nervous
system such as smooth muscle, cardiac muscle, and glands.
3. Enteric nervous systemcontrols digestive organs only!
- Network of fibres that are localised in digestive track.
, Vision as an example
The part of the brain that controls the vision is in the cortex and localised in the occipital
region.
ü Features of the eyes
- Iris= gives the eyes the colour
- Pupil= round opening through which the light enters the eye.
- Sclera= made of up of connective tissue. Tough outer layer of the eye
ü Structures that protect the eye.
- Eye lids= protects from mechanical issue
- Eyelashes= traps fine particles
- Tears= lubricant and germ-killing fluid
Tears are produced by lacrimal gland and drains into tiny canals and reaches lacrimal
sacs.
The eye is a fluid filled structure.
Has 3 different layers
1. External sclera (outermost layer)
2. Choroid (middle layer which is highly pigmented)
3. Retina (innermost layer) that contains photoreceptors.
The eye contains 2 separate cavities that are separated by analytical lens. (Lens must be
transparent to let the light in)
1. The region between the lens and the retina is filled with vitreous humor (also
transparent) which helps to maintain the spherical shape of the eyeball.
2. Between the lens and the cornea and this is filled with aqueous humor.
Iris muscle is controlled by automimic system to dilate and contract.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller uneebihsan28. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £14.16. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
70055 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now