A & P lab practical

Upper/lower eyelid

External feature of the eye

Lacrimal gland

gland located in the upper outer region above the eyeball that secretes tears

excretory lacrimal ducts

lacrimal fluid produced by the gland is secreted into these, which empty into the superior conjunctival fornix. The fluid is then 'spread' over the cornea by the process of blinking

Lateral/Medial rectus

Moves eye left and right

Superior/Inferior rectus

move eye up and down

Superior/Inferior oblique

rotate eye opposite their name and also laterally

Pupil

The opening through which light enters the eye

Iris

a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

Sclera

white of the eye; fibrous tunic (outer layer)

Cornea

The clear tissue that covers the front of the eye

Conjunctiva

Delicate membrane lining the eyelids and covering the eyeball

Lens

structure in the eye that focuses light rays on the retina

Optic nerve

the nerve that carries neural impulses from the eye to the brain

Optic disk

A hole in the retina where the optic nerve fibers exit the eye.

Macula

yellowish region on the retina lateral to and slightly below the optic disc that produces sharper vision

Fovea centralis

tiny pit or depression in the macula that is the region of clearest vision

Choroid

Middle layer of the eye (vascular tunic) that includes the iris, pupil, and ciliary body/muscle

Ciliary body and muscle

Body: controls the shape of the lens, and the ciliary epithelium, which produces the aqueous humor. Muscle: controls accommodation for viewing objects

Retina

Inner "nervous" layer of the eye

Anterior cavity

contains aqueous humor that helps maintain shape of eyeball and supplies oxygen and nutrients to lens and cornea

Posterior cavity

Contains vitreous humor/body

Auricle

external ear

External acoustic meatus

ear canal

Tympanic membrane

eardrum

Oval window

membrane at the enterance to the cochlea through which the ossicles transmit vibrations

Round window

The membrane that relieves pressure from the vibrating waves in the cochlear fluid.

Malleus

hammer; first of the three auditory ossicles of the middle ear

Incus

anvil; middle of the three auditory ossicles of the middle ear

Stapes

stirrup; last of the three auditory ossicles of the middle ear

auditory (eustachian) tube

channel between the middle ear and the nasopharynx

Vestibule

The portion of the inner ear that senses the position of the head. Its sensory epithelium is contained in two saclike spaces: the utricle and the saccule.

Cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

Semicircular canals

three canals within the inner ear that contain specialized receptor cells that generate nerve impulses with body movement

vestibulocochlear nerve

transmits hearing and balance impulses to the brain

Meninges

Protective membranes surrounding the brain and spinal cord

Dura Mater

Outermost and toughest layer of the meninges

Arachnoid mater

Middle layer of the meninges, filled with cerebrospinal fluid

Pia Mater

Innermost layer of the meninges, directly attached to the brain and spinal cord

Cerebrum

Largest part of the brain responsible for higher functions such as intellect, creativity, awareness, and language

Frontal Lobe

Part of the cerebrum responsible for higher functions such as intellect, creativity, awareness, and language

Parietal Lobes

Part of the cerebrum responsible for receiving sensory information from the body

Temporal Lobes

Part of the cerebrum containing the primary auditory cortex and responsible for hearing

Occipital Lobe

Part of the cerebrum responsible for vision

Central sulcus

A groove that divides the frontal and parietal lobes

Diencephalon

Contains thalamus and hypothalamus

Thalamus

Part of the diencephalon that receives almost all sensory information from the body and sends it to the cerebral cortex

Hypothalamus

Part of the diencephalon involved with the autonomic nervous system and pituitary gland, and responsible for functions such as thirst, hunger, temperature regulation, pleasure, sexual desire, and aggression

Pituitary Gland

Gland in the brain that controls many hormones in the body

Pineal Gland

Gland in the brain that secretes melatonin, which regulates daily sleep/wake rhythms

Midbrain

Part of the brainstem involved in sensory and motor functions

Pons

Part of the brainstem involved in relaying signals between the cerebrum and cerebellum and handles some unconscious processes

Medulla Oblongata

Part of the brainstem responsible for vital functions such as breathing and heart rate

Cerebellum

Part of the brain responsible for balance, coordination, and planning

White and Grey matter

Tissues that make up the spinal cord, with white matter containing nerve fibers and grey matter containing cell bodies

Ventral and Dorsal root

Nerve roots that emerge from the spinal cord, with ventral roots carrying motor signals and dorsal roots carrying sensory signals

Dorsal horn

Part of the spinal cord grey matter that receives sensory information

Dorsal root ganglion

Cluster of sensory neuron cell bodies located in the dorsal root

Spinal nerve

Nerve that emerges from the spinal cord and carries both sensory and motor signals

Conus medullaris

End of the spinal cord, usually at the level of the first or second lumbar vertebra

Cauda equina

Bundle of spinal nerves below the conus medullaris

Filum terminal

Thin strand of fibrous tissue that extends from the conus medullaris and anchors the spinal cord

Cervical plexus

Plexus formed by spinal nerves C1-C4, serving the neck and upper shoulder

Brachial plexus

Plexus formed by spinal nerves C5-T1, serving the upper limb

Lumbar plexus

Plexus formed by spinal nerves L1-L4, serving the lower abdomen and anterior thigh

Sacral plexus

Plexus formed by spinal nerves L4-S4, serving the posterior thigh, leg, and foot

Neurons

Nerve cells responsible for transmitting information in the nervous system

Axon

Long fiber of a neuron that carries nerve impulses away from the cell body

Dendrite

Branch-like extension of a neuron that receives signals from other neurons

Neuron cell body

Part of a neuron that contains the nucleus and other organelles

Myelin

Fatty substance that surrounds and insulates axons, allowing for faster transmission of nerve impulses

Peripheral nerves

Nerves that connect the central nervous system to the rest of the body

Median nerve

Nerve in the upper extremity responsible for sensation and movement in the thumb and first three fingers

Radial nerve

Nerve in the upper extremity responsible for sensation and movement in the back of the hand and forearm

Ulnar nerve

Nerve in the upper extremity responsible for sensation and movement in the pinky finger and part of the ring finger

Femoral nerve

Nerve in the lower extremity responsible for sensation and movement in the front of the thigh and lower leg

Sciatic nerve

Nerve in the lower extremity responsible for sensation and movement in the back of the thigh, leg, and foot

Tibial nerve

Nerve in the lower extremity responsible for sensation and movement in the back of the leg and sole of the foot

Fibular nerve

Nerve in the lower extremity responsible for sensation and movement in the front of the leg and top of the foot

Cranial Nerves

Nerves that emerge directly from the brain and serve various functions

CN I

Olfactory nerve responsible for sensations for smelling

CN II

Optic nerve responsible for sensations for vision

CN III

Oculomotor nerve responsible for motor control of eye movements

CN IV

Trochlear nerve responsible for motor control of the superior oblique eye muscle

CN V

Trigeminal nerve responsible for sensory input from the head and motor control to the head

CN VI

Abducens nerve responsible for motor control of lateral eye movements

CN VII

Facial nerve responsible for sensory input from the anterior tongue and motor control to head muscles

CN VIII

Vestibulocochlear nerve responsible for sensory input for hearing and vestibular function for balance

CN IX

Glossopharyngeal nerve responsible for mixed sensory and motor functions for the tongue and throat

CN X

Vagus nerve responsible for sensory input from the abdomen, thorax, neck, and tongue, and motor control to the pharynx and larynx, as well as autonomic functions

CN XI

Accessory nerve responsible for motor control of neck muscles

CN XII

Hypoglossal nerve responsible for motor control of the tongue

What are the facial muscles?

Temporalis, Masseter, Orbicularis Oculi, Orbicularis Oris, Zygomaticus Major, Buccinator

What is the function of the temporalis muscle?

Mastication (chewing)

What is the function of the masseter muscle?

Mastication (chewing)

What is the function of the orbicularis oculi muscle?

Winking, closing eye

What is the function of the orbicularis oris muscle?

Kissing, speech

What is the function of the zygomaticus major muscle?

Smiling, laughing

What is the function of the buccinator muscle?

Whistling, blowing

What is a major muscle of the neck?

Sternocleidomastoid

What is the function of the sternocleidomastoid muscle?

Rotation of head to opposite side and flexion of neck