Biology final exam

Why is Vitamin A essential for vision?

Vitamin A is retinol and is modified to retinal, the visual pigment

All preganglionic axons in the autonomic nervous systems produce the neurotransmitter ____________________

acetylcholine

Postganglionic axons of the parasympathetic system release this neurotransmitter _________________.

acetylcholine

What is meant by adrenergic receptors? Cholinergic receptors?

adrenaline/norepinephrine receptors. acetylcholine receptors

The anterior segment is filled with _____________________________.

aqueous humor

In terms of pathways associated with the special senses, what is unique about the olfactory pathway?

it is the only sensory pathway that is not routed through the thalamus.

The structure that produces tears to moisten, lubricate, and wash the eyes is the ________________________________.

lacrimal apparatus.

Static equilibrium (response to linear acceleration, riding up or down in an elevator, etc.) is a function of the ___________________ and _________________.

maculae

What does olfaction refer to ?

smell or sense of smell

The lens of the eye is held in place by _______________________________ which are in turn attached to the ciliary muscles.

suspensory ligaments

List the basic taste sensations.

sweet, sour, bitter, salty, umami

Which system exhibits thoracolumbar outflow?

sympathetic

Which system is referred to as the "fight or flight" system?

sympathetic

Where would gustatory hairs be found?

taste buds

Give an example of a chemoreceptor. A photoreceptor. A mechanoreceptor.

taste/smell. rod and cone cells of the retina. hearing and balance among others

In what lobe is the olfactory cortex located?

temporal

List the four types of papillae found on the tongue. Which ones house taste buds?

Filiform, fungiform, foliate, circumvallate (vallate). All but filliform.

This region, the center of the macula, is where most light is focused on the retina and it consists only of cone cells?

Fovea centralis

What is the effect of glutamate on the bipolar cells of the retina?

Glutamate hyperpolarizes the bipolar cells (i.e., an IPSP)

This clinical test for normal eye movement is called the _____________ test.

H test

Hyperpolarization of the rod cell has what effect on the bipolar cell? (See PowerPoint slide#60)

Hyperpolarization of the rod cells slows glutamate release and thus the inhibition of the bipolar cells so that the bipolar cells release neurotransmitters that stimulate the ganglion cells.

The maculae are located in the __________________ and _________________ of the vestibule.

Saccule and Utricle

Name the three coats (tunics) of the eye. Which one is referred to as the "vascular tunic"?

Sclera, uvea, sensory(retina). Choroid of the Uvea

What are splanchnic nerves?

Splanchnic nerves pass through the autonomic ganglia without synapsing and extend to the structure being innervated (e.g., the adrenal medulla).

The cavity of the cochlea contains three chambers. Name the three chambers and describe their respective positions (superior, inferior, etc.). What is the helicotrema?

Superior - scala vestibuli runs from the oval window to the helicotrema (perilymph) Middle - scala media or cochlear duct (endolymph) Inferior - scala tympani runs from helicotrema to round window (perilymph)

The posterior segment of the eye (behind the lens) is filled with a viscous material called __________________________.

vitreous humor

What is meant by the term anosmia?

without smells- the inability to detect odors.

Name the three processes that occur simultaneously as we adjust/focus for close vision?

Accomodation of the lenses (bulge on lens increases as we move the focal point closer) Constriction of the pupils Convergence of the eyeballs

What is an uncinate fit?

An olfactory hallucination - usually an unpleasant odor

Between the sphincter papillae and dilator papillae.

As the names imply, the sphincter pupillae constricts the pupil. and the dilator pupillae dilates the pupil.

This structure is found within the cochlear duct and is the receptor for hearing: ___________________

organ of Corti

Which system exhibits craniosacral outflow?

parasympathetic

Which system is referred to as the "resting and digesting" system?

parasympathetic

The autonomic system uses a two-neuron chain. In the ____________________ system, long preganglionic fibers and short postganglionic fibers are typical; in the _____________________ system, short preganglionic fibers and long postganglionic fibers are typical.

parasympathetic, sympathetic

What is presbyopia? Myopia? Hyperopia? Astigmatisum? Nyctalopia?

1. As we age, the lens loses its elasticity and thus its ability to focus on close objects. 2. Nearsighted 3. Farsighted 4. An unequal curvature of the lens 5. Night blindness

Place these steps in the correct order (cAMP opens ion channels in the membrane, odorant molecule binds to odorant receptor in cell membrane, adenylate cyclase catalyzes the conversion of ATP to cAMP, G Protein complex detaches from odorant receptor, alpha subunit of G Protein complex binds with adenylate cyclase and activates the enzyme)

2. an odorant binds to a specific odorant receptor. 3. the associated G protein is activated. The a,b, and y subunits dissociate. the a subunit of the Gprotein binds to and activate adenylate cyclase. 4. Adenylate cyclase catalyzes the conversation of AyP to cyclic AMP (cAMP). 5. cAMP opens ion channels, such as Na+ and Ca2+ channels. 6. ions entering the olfactory hair cause depolarization of the neuron.

Light absorption by rhodopsin triggers a rapid series of steps in which retinal changes shape from _________________ to the _______________________ isomer and then detaches from opsin.

Cis- to the all trans-

In this photoreceptor, the inner segment directly joins the cell body?

Cone cells

The sensory receptor cells in the retina which are responsible for high acuity color vision are the ______________

Cone cells

This thin, transparent membrane lines the eyelids and covers the anterior surface of the eye?

Conjunctiva

Kinetic (dynamic) equilibrium is a function of the ___________________ ____________________________.

Crista Ampullaris.

What is meant by dual innervation?

Dual innervation refers to the fact that organs innervated by the ANS are typically innervated by both divisions. In general what one division stimulates in that organ/gland, the other division inhibits so that there is a built in "check" or check and balance system.

What is the function of the pharyngotympanic tube?

Equalization of air pressure between the middle ear and the atmosphere

What are palpebrae? Canthi? Lacrimal caruncle?

Eyelids. The corners of the eye. Medial and Lateral.

What is the function of the crista ampullaris? The cupula?

Kinetic equilibrium - rotational movements of the head set fluids within the semicircular canals into motion. The crista ampullaris detects movement of these fluids

Name the three auditory ossicles. Name the structure that separates the outer ear from the middle ear.

Malleus, incus, stapes Tympanum or tympanic membrane

The inner ear is divided into a bony labyrinth and a membranous labyrinth. Which contains endolymph? Perilymph?

Membranous labyrinth contains endolymph. Perilymph- The bony labyrinth

What are otoliths?

Otoliths are literally "ear stones". They are actually calcium carbonate crystals which are embedded in the otolithic membrane and they serve to increase its inertia once it goes into motion.

This muscle raises the upper eyelid? This muscle surrounds the eye and we use it when me wink at someone?

Parasympathetic

Distinguish between paravertebral and prevertebral ganglia of the sympathetic (thoracolumbar) system?

Paravertebral (chain ganglia) run parallel to the spinal cord in the thoracolumbar region (on each side of the spinal cord/vertebral column).

Name the three main types of neurons that make up the retina.

Photoreceptors Bipolar cells Ganglion cells

What are the two layers of the retina?

Pigmented layer (simple cuboidal epithelium) and the neural layer

prevertebral ganglia of the sympathetic (thoracolumbar) system?

Prevertebral (in front of the vertebral column) ganglia lie on the anterior surface of the aorta and the names of most of these ganglia correspond to blood vessels branching of the aorta (i.e., superior mesenteric artery/superior mesenteric ganglia).

The receptors responsible for non-color vision (dim light) are __________________.

Rod cells

What is the cornea?

The cornea is the transparent, anterior 1/6 of the sclera which allows light to enter the eye.

Distinguish between intrinsic and extrinsic eye muscles?

The extrinsic eye muscles are involved with movement of the eye (superior, inferior, medial,and lateral rectus and the superior and inferior oblique muscles). Instrinsic (meaning within) muscles are the sphincter pupillae and dilator pupillae.

What is the function of the cupula ?

The hair cells of the crista ampullaris are embedded in a gelatinous mass called the cupula so that fluid movement bends the cupula as well as the emeshed hair cells.(PowerPoint slide #93)

Distinguish between iris and pupil.

The iris is the colored portion of the eye (a portion of the uvea). The pupil is a reflexively activated diaphragm within the iris that allows light to enter the eye.

What is the function of the tensor tympani and stapedium muscles?

The tensor tympani attaches to the malleus and the stapedium attaches to the stapes. Both muscles contract reflexively to prevent damage to the hearing receptors

Distinguish between muscarinic and nicotinic receptors. ACh binding to ___________________ receptors is almost always stimulatory.

These are two classes of receptors based on their response in one case to nicotine, a plant alkaloid, and in the other case to muscarine, a compound found in certain fungi. Nicotinic

What is the helicotrema?

This represents the junction of the scala vestibuli and the scala tympani.

Name the structure that produces aqueous humor.

ciliary process

These are the largest of the papillae and they are found in a "V" shaped row on the back of the tongue?

circumvallate

If aqueous humor is produced at a faster rate than it drains from the anterior segment of the eye, this condition results in: _____________________________

glaucoma

Postganglionic axons of the sympathetic system release this neurotransmitter: __________________.

norepinephrine

What is meant by the term emmetropic?

normal eye 20/20 vision

The fact that visceral pain afferents travel along the same pathway as somatic pain fibers helps to explain the phenomenon of ______________ _____________.

referred pain

The major portion of parasympathetic cranial outflow is via the _______________ nerve.

vagus nerve