ADLC Biology 30 - Module 1: The Nervous System (Sensory Reception)

Vocabulary flashcards covering sensory adaptation, gustation, olfaction, tactile acuity, eye structures, visual processing, and photoreceptor functions from Biology 30 Module 1.

Sensory adaptation

The process that occurs when the brain filters out repetitious and/or insignificant information.

Chemoreceptors (Taste)

Receptors in the taste buds on the surface of the tongue that initiate a nerve impulse to the brain only when chemicals are dissolved in saliva.

Parietal lobe (Taste pathway)

The lobe of the cerebrum responsible for perceiving taste sensations detected by taste buds.

Olfactory sensory pathway

The transmission pathway for smell: sensory receptors $\rightarrow$ sensory neurons $\rightarrow$ olfactory bulb $\rightarrow$ cerebrum.

Tactile acuity

The minimum separation required between two points for the brain to perceive them as two separate points.

Sclera

The outer eye structure that protects and supports the eyeball.

Vitreous humour

Fluid-containing structure that supports the shape of the eyeball.

Ciliary muscles

Muscles that alter the shape of the lens to promote focusing on both near and distant objects.

Iris

The structure that relaxes and contracts to regulate the amount of light entering the eye and protect the retina from excess light.

Cornea

The front structure of the eye that refracts and bends light rays into the eye.

Lens

A flexible structure that bends light to focus rays onto the fovea centralis of the retina.

Choroid

A layer of the eye that absorbs scattered light.

Fovea centralis

The specific area of the retina that contains a high density of cone photoreceptors.

Rods

Photoreceptors of the retina concentrated at the periphery that are sensitive to dim light and register black and white.

Cones

Photoreceptors concentrated in the fovea of the retina responsible for detecting colours.

Visual field perception

The sensory organization in which the left visual fields from both eyes are processed on the right side of the cerebrum.

Binocular vision

Vision involving two forward-facing eyes that provides depth perception by analyzing differences between the images falling on the left and right eyes.

Hyperopia

A condition in which the eye cannot view close objects clearly; in newborns, it is caused by weak ciliary muscles that do not pull adequately on the light and flexible lens.

Dark adaptation

The adjustment process when moving from a bright environment into a dark room that can take more than $10\text{ minutes}$ while waiting for the rods to begin functioning.

Colour blindness

A visual defect resulting from the loss of specific types of cones or having fewer cones of a given type (such as having $50\%$ fewer green cone photoreceptors, leading to difficulty distinguishing green hues).