BIO168 Unit 4 Study Guide Flashcards

Vocabulary flashcards covering anatomy and physiology topics from BIO168 Unit 4 Study Guide.

Cranial Nerves CNIII, CNIV, and CNVI

Oculomotor CNIII, Trochlear CNIV, and Abducens CNVI are all three cranial nerves that move the eye, tested by having a patient follow the motion of a finger across their visual field.

Olfactory CNI Damage

Potential damage indicated by the inability to distinguish odors.

Dermatome Maps

Maps useful for showing the level of a spinal injury; for example, being numb from the umbilicus down indicates a likely spinal injury at ~T10.

Nociceptors

Sensory receptors that detect pain, including burning or freezing pain.

Crossed-Extensor Reflex

A reflex where flexion occurs in the affected limb and extension occurs in the unaffected limb.

Vestibulocochlear Nerve Trauma

Trauma to this nerve (CNVIII) results in balance problems.

Sacral Plexus

A nerve plexus formed by spinal nerves L4-S4.

Mechanoreceptors

Receptors that detect tactile sensations like touch, pressure, and stretch.

Proprioceptors

Receptors that enable touching our nose with eyes closed and awareness of the body's positioning.

Simple Spinal Reflex Arc

A pathway composed of five components: a. Receptor, b. Afferent neuron, c. Integration center, d. Efferent neuron, e. Effector.

Phrenic Nerve Origin

Arises from the cervical plexus, whereas the radial, median, and ulnar nerves arise from the brachial plexus.

Sensory Adaptation

Process involving receptors becoming less responsive to a constant stimulus.

Structures of the PNS

Peripheral nervous system components including ganglia, cranial nerves, and spinal nerves.

Accessory CNXI Clinical Test

Shrug resistance testing the trapezius muscle.

Golgi Tendon Reflex

The reflex that causes muscle lengthening and relaxation in response to tension.

Prefrontal Cortex

A region of the brain that is not involved in a reflex arc.

Fight or Flight Response

Sympathetic response in a startling/frightening situation leading to increased metabolic rate, increased rate and force of heartbeats, and inability to read close-up print due to its effect on the lens.

Autonomic Ganglia

Ganglia containing motor neuron cell bodies.

Splanchnic Nerves

Fibers that enter and leave the sympathetic trunks without synapsing.

Effects of Sympathetic Stimulation

Autonomic effects including increased blood glucose, decreased GI peristalsis, and increased heart rate and blood pressure.

Adrenal Medulla Response

Release of NE and EPI from the adrenal medulla leading to widespread, long-lasting sympathetic responses to supplement the sympathetic nervous response.

Vagus CNX

Cranial nerve that innervates most of the smooth muscle of the digestive viscera.

Beta Blockers

Drugs that inhibit $\beta_1$ receptors, leading to a decrease in heart rate and blood pressure.

ANS Preganglionic Neurotransmitter

Acetylcholine (ACh), which is used by all ANS preganglionic neurons whether sympathetic or parasympathetic.

Cholinergic Receptors

Receptors divided into two major categories: nicotinic and muscarinic.

Spinal Cord Lateral Horns

Structures containing autonomic motor neuron cell bodies.

Effects of Parasympathetic Stimulation

Autonomic effects including increased peristalsis of the digestive viscera, salivation, pupil constriction, and elimination of urine.

Transduction

The conversion of stimulus information to nerve impulses.

Cochlea

The anatomical location of the receptors for hearing.

Blind Spot

Area of the eye caused by the lack of photoreceptors where the optic nerve leaves the eye.

Rods

Photoreceptors that give grayscale vision in dim light.

Iris

Structure that regulates the amount of light passing to the visual receptors of the eye.

Pharyngotympanic Tube

Also known as the eustachian tube, a structure of the middle ear.

Taste Sensations and Chemical Matches

Sour matches acids, Salty matches metal ions, Sweet matches organic substances like sugar and some lead salts, Bitter matches alkaloids, and Umami matches amino acids, particularly glutamate.

Light Pathway Through the Eye

The sequential path of light through the eye: cornea, then aqueous humor, then lens, then vitreous humor.

Gustatory Transduction Sequence

Chemical binds to receptor on gustatory cell -> ion movements depolarize cell -> voltage-gated calcium channels open and calcium enters -> neurotransmitters released -> action potential produced in sensory neuron.

Photoreceptor Transduction

In darkness, cells continuously depolarize and release glutamate as an inhibitory neurotransmitter; light causes cessation of depolarization, disinhibiting the bipolar sensory neuron and causing an action potential.

Auditory Transduction Mechanism

Sound moves basilar membrane up toward tectorial membrane -> bends stereocilia toward tallest stereocilium -> opens potassium channels -> depolarizes hair cell -> releases neurotransmitters -> triggers action potential in cochlear nerve.

Color Blindness

Condition where typically red and green cones are absent, especially in the foveae.

Accommodation

Reflex where ciliary body contracts so the lens bulges outward and the iris constricts so the pupil gets smaller when an object being viewed gets closer to the eye.

Sensory Input for Equilibrium vs. Hearing

Equilibrium depends on visual system, vestibular system, and proprioceptors in muscles/joints; hearing depends on input from the cochlea.

Crista Ampullaris

Structure responsible for dynamic equilibrium.

Utricle and Saccule

Structures responsible for static equilibrium.

Superior Rectus

Eye muscle that elevates the eye.

Inferior Rectus

Eye muscle that depresses the eye.

Superior Oblique

Eye muscle that depresses and turns the eye laterally (down and out).

Inferior Oblique

Eye muscle that elevates and turns the eye laterally.

Lateral Rectus

Eye muscle that turns the eye laterally (abduction).

Medial Rectus

Eye muscle that turns the eye medially (adduction).

Levator Palpebrae Superioris

Eye muscle that elevates the upper eyelid (opens eye).

Orbicularis Oculi

Eye muscle that closes the eye.