Class Notes (839,113)
Canada (511,191)
Biology (2,271)
BIOL 130 (308)
Lecture 15

Outline of Lecture 15

3 Pages
88 Views

Department
Biology
Course Code
BIOL 130
Professor
Barry Mc Clinchey

This preview shows page 1. Sign up to view the full 3 pages of the document.
Description
Outline of Lecture 15 Special Senses: Eye, Ear, and Nose I. Overview of sensory cells of the eye, ear, and nose - Due to evolution, the cilia of sensory cells are on the topographical outer surface of the body - Quickies on each system - Eye: signal through a 7TM containing rhodopsin, coupled to G-protein; retina is part of the forebrain (diencephalon), lens derives from lens placode of surface ectoderm - Ear: mechanoreceptive cilia directly tranduce vibration to ion channel opening; derives from otic placode of ectoderm overlying hindbrain (rhombomeres 5,6) - Nose: odorant binds and signals through GPCR/cAMP; derives from olfactory placode of forebrain (telencephalon) II. The Eye A) Embryology of the eye - Optic vesicle derives from neural plate, lens from surface ectoderm - Neural crest and mesoderm contribute to other eye tissues (cornea, choroids, sclera, etc) - Shh splits the eye field by inhibiting eye dev. along the midline - Reciprocal induction: BMP4 and BMP7 from optic vesicle induces lens primordium, and FGF1 and FGF2 from lens induces optic vesicle (eye primordium) - PAX6 can induce eye development ectopically B) Layout of the optic cup - Lens placode pinches off to form lens vesicle; surface ectoderm becomes cornea - Optic vesicle invaginates to form optic cup around the lens (ventral portion fuses) - Inner layer of optic cup becomes retina and outer layer becomes retinal pigment epithelium - Photoreceptors point away from light into ventricular space between layers of optic cup - Fovea at back of retina is thinner to allow for sharper vision at that region (less non-photoreceptor cells in the way to scatter light) C) Cells types of the retina - Ganglion cells: their axons project through optic nerve to brain; formation requires Math5 txn factor - Bipolar cells: relay signals from photoreceptors to ganglions; dev. requires Chx10 txn factor - Mueller glial cells: retina scaffold, ganglion axon guidance, neurotransmitter recycling - Amacrine and horizontal cells: no detail given - Photoreceptors - Rods: for low light - Cones: comes in red, green, blue - Photosensitive ganglions: involved in pupil contraction and circadian rhythm; detect light with melanopsin (this is Wai-King Yau’s work) D) Eye connections to brain - Portion of ganglions from each eye cross brain midli
More Less
Unlock Document

Only page 1 are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit