BIO 66 – HUMAN PHYSIOLOGY Short Answer Key

A collection of vocabulary flashcards covering key concepts from the BIO 66 human physiology notes.

Pupillary light reflex

The reaction where shining light into one eye causes both pupils to constrict; involves direct and consensual reflexes due to parasympathetic control.

Jendrassik maneuver

A technique used to enhance the strength of the knee-jerk reflex by reducing descending inhibition of spinal reflex arcs.

Ingersoll eye model

Demonstrates accommodation by changing lens power; involves ciliary muscle contraction for near vision.

Convex lens for hyperopia

A lens that corrects farsightedness by converging light before it enters the eye, moving the focal point to the retina.

Referred pain

Pain perceived at a location other than the site of the stimulus, due to convergence of afferent signals at the spinal level.

Barany chair

A device used to stimulate semicircular canals; stopping the rotation causes post-rotatory nystagmus due to endolymph movement.

Nernst potential

The voltage at which the electrical and chemical forces on an ion are balanced, such as the approximate -61 mV for K+.

Two-point discrimination

A sensory test that measures the ability to perceive two points on the skin, dependent on receptor density.

Audiometer testing

A method used to measure hearing thresholds by increasing sound intensity at different frequencies until detected.

Taste and Olfaction

Taste testing with PTC paper identifies tasters; olfactory adaptation occurs with repeated exposure reducing perception.

Recruitment in motor units

The process of activating additional motor units to increase muscle force during graded contractions.

Summation in muscle contractions

The increase in tension due to multiple stimuli before complete calcium clearance; tetanus is maximal sustained contraction.

Latent period

The time between action potential and muscle tension generation, during excitation-contraction coupling.

Nerve conduction velocity

The speed at which a nerve impulse travels, measured by stimulating a nerve and timing the EMG response.

Co-activation of muscles

The phenomenon where an agonist contracts under load while the antagonist shows mild activity to stabilize the joint.

Effect of encouragement after fatigue

Temporary increases in grip force following encouragement, compared to immediate post-fatigue levels.

Visual feedback in sustained effort

The use of visual information to help maintain higher grip force by improving control and motivation.

Causes of muscle fatigue

Factors like potassium buildup, lactic acid production, reduced calcium release, and glycogen depletion during prolonged activity.

Types of muscle tissue

Skeletal muscle is striated and voluntary; cardiac muscle is striated and involuntary; smooth muscle is non-striated and involuntary.