Biol 216 - Topic 7: The Senses

This set of flashcards covers key vocabulary and definitions related to the anatomy and physiology of the visual system as discussed in the course on the senses.

Retina

Layer of neural cells that lines the back of the eye, contains photoreceptor cells sensitive to light.

Photoreceptors

Specialized cells in the retina (rods and cones) that detect light and convert it into electrical signals.

Fovea

Region of the macula in the retina with a high density of cone cells, involved in high acuity vision.

Ciliary Muscle

Ring of smooth muscle fibers that changes the shape of the lens for focusing.

Rods

Photoreceptor cells that are specialized for detection of low-intensity light.

Cones

Photoreceptor cells specialized for detecting color and high acuity vision.

Rhodopsin

Photopigment in rod cells that is sensitive to light; composed of retinal and opsin.

Iodopsin

Photopigment found in cone cells, containing different types of photopsin for color detection.

Ciliary Body

Part of the eye that includes the ciliary muscle and produces aqueous humor.

Aqueous Humor

Thin, watery fluid found in the anterior and posterior chambers, helps maintain intraocular pressure.

Vitreous Humor

Thick, gel-like fluid that maintains the shape of the eye and absorbs shocks.

Direct Pathway of Vision

The pathway where light signals are processed from photoreceptors to bipolar cells to ganglion cells.

Amacrine Cells

Neurons in the retina that modulate the processing of visual information from bipolar cells.

Horizontal Cells

Cells in the retina that help process visual signals by connecting photoreceptors to bipolar cells.

Visual Acuity

The sharpness or clarity of vision, predominantly attributed to the functioning of cone cells.

Blind Spot

Area in the retina where the optic nerve exits; lacks photoreceptor cells, thus not perceivable visually.

Accommodation

The process by which the eye changes lens shape to focus on near or distant objects.

Visual Processing

The complex procedures that the brain undertakes to interpret visual information from the retina.

Ganglion Cells

Neurons in the retina that receive visual information from bipolar cells and transmit it to the brain via the optic nerve.

Depth Perception

The ability to perceive distance; relies on visual input from both eyes.

Lateral Geniculate Nucleus (LGN)

Part of the thalamus that acts as a relay center for visual information from the optic nerve to the visual cortex.

Phototransduction

The biochemical process by which photoreceptors convert light into electrical signals.

Dark Adaptation

The process by which the eyes become more sensitive to light in low light conditions.

Light Adaptation

The process by which the eyes reduce sensitivity to light in bright light conditions.