PHYSIO QBANK Flashcards
Functions of the retinal pigment epithelium
Phagocytosis of rod and cone outer segments
Transport and storage of metabolites and vitamins
Selectively permeable barrier between the choroid and neuroretina
Melanin of the RPE assists in the absorption (not reflection) of light within the eye, thus reducing scatter
How many rods are there in the retina:
115 million
Rod photoreceptors: inner and outer
The inner half of the inner segment is known as the myoid while the outer half of the inner segment is known as the ellipsoid.
Myoid contains numerous organelles including Golgi apparatus and smooth ER Ellipsoid contains numerous mitochondria.
inner inner myoid
Smooth muscle contains?
Smooth muscle shows no visible striation. It is innervated by the autonomic nervous system. It contains myosin, actin and tropomyosin, but not troponin
The corneal epithelium utilizes most of its glucose:
The corneal epithelium utilizes most of its glucose (85%) for the production of ATP via glycolysis anaerobically with lactate production.
Meissner’s corpuscles:
light touch
Pacinian corpuscles:
pressure and vibration receptors
Merkel discs:
light touch
Free nerve endings:
pain and temperature
The main collagen of the corneal stroma is:
Type I collagen comprises 50-55% of the collagen in the corneal stroma
