A&P II -- Final Exam Flashcards
What is sensation?
Conscious awareness of the effects of stimuli, received by sensory receptors. The brain perceives info about body and environment via senses.
What are the 5 types of sensory receptors according to the categorized by the type of stimulus?
Mechanoreceptors: Respond to manual stimulus tickle, touch, vibration.
Chemoreceptors: Respond to different chemicals. Smell and taste.
Thermoreceptors: Respond to change in temperature.
Photoreceptors: Respond to light. Sense of vision.
Nociceptors (pain receptors): Extreme mechanical, chemical or thermal stimuli. Causes sense of pain.
What are the 3 types of receptors catergorized by location?
Exteroreceptors: Associated with skin
Visceroreceptors: associated with organs.
Proprioceptors: Associated with joints and tendons.
What are Direct Pathways and what are their two tracts?
Control fine, skilled movements in the face and distal limbs
Corticospinal: direct control of movements below the head
Corticobulbar: direct control of movements in head and neck
What are the four special senses?
Olfaction, Taste, Sight and Balance
What kind of neurons are found in the olfactory system?
Bipolar Neurons which have 1 axon and 1 dendrite.
What are the three regions of the frontal lobe that affect the perception of smell?
Lateral Olfactory Area: Concious perception of smell
Medial Olfractory Area: Visceral and emotional reactions to smell
Intermediate Olfactory Area: affect modification of incoming information.
What are the 4 types of papillae in the tongue?
Vallate: Largest, least numerous. In the middle area of tongue.
Fungiform: Mushroom-shaped. Scattered irregularly over the superior surface of tongue.
Foliate: Leaf-shaped. In folds on the sides of the tongue. Decrease in number with age.
Filiform: fiber shaped. Most numerous on the tongue surface.
What are the five types of taste types?
Sour: Caused by Hydrogen ions
Salty: Caused by Sodium ions
Bitter: presence of g-protein that open gated channels
Sweet: Sugars and carbs. carbs break down into sugars.
Umami: Caused by amino acids. Found in rich aged foods.
What are the 5 accessory structures of the visual system?
Eyebrows: inhibit sweat
Eyelids (palpebrae): help lubricating the eyes and protect the eyes from foreign objects.
Conjunctiva: thin transparent mucous membrane. Covers the inner eyelid and part of the eye;
Lacrimal glands: produce tears (lubrication and protection of the eye);
Extrinsic eye muscles: move the eyeball (clinical test for normal eye movement – “H” test).
What are the four areas of the lacrimal apparatus?
Lacrimal gland: produces tears to moisten, lubricate, wash. Tears pass through ducts and then over eye.
Lacrimal canaliculi: collect excess tears through openings called “puncta” in the corner of eye.
Lacrimal sac: collects excess tears to drain through nasolacrimal duct.
Nasolacrimal duct: opens into nasal cavity
What are the three layers of the eyeball?
Fibrous Tunic (outer layer): contains sclera and cornea
Vascular tunic (middle layer): choroid, ciliary body, iris. Contains most of the blood vessels in eye.
Nervous tunic (inner layer): retina
What is the sclera?
The outer white area of the eye that is made of dense collagenous connective tissue.
Maintains shape and protects internal structures of eye
What is the cornea?
The transparent front area of the eye. Its is transparent to allow light to enter the eye
What are the two sublayers of the Nervous layer?
Pigmented retina: reduce light scattering
Sensory retina: contains rod and cone cells that are sensitive to light. Only area that contains photoreceptors.
What does the area of light focus in the retina consist of?
Macula Lutea and Fovea Centralis
Describe the Fovea Centralis?
The dark spot in center of retina. Contains the highest area of visual ability and the most photoreceptor cells.
What is the name of the blind spot in your eye? Why is it called the blind spot?
Optic Disc.
It is called the blind spot because it contains no photoreceptors and only contains a port in which blood vessels and the optic nerve enter/exit the eye.
Describe the focal point and where is the ideal place for it on the retina?
It is the crossing point for all converging light rays. The ideal focal point is the fovea centralis.
Describe Rods
A photoreceptor cell responsible for black and white vision. Found over retina but not in fovea centralis.
Has two components opsin and retinal
Describe Cones
Photoreceptor cells responsible for color vision and visual acuity. Found mostly in fovea centralis and macula lutea.
How does light travel through the retina?
The action potential first reaches the pigmented layer of the retina —> then goes through the photoreceptor layer containing rods and cones —> then the AP reaches the bipolar cells —> reaches the ganglion cells —> then transfers to the optic nerve.
Describe the eye disorders myopia and hyperopia
Myopia (near-sightedness) Focal point too near lens, image focused in front of retina
Hyperopia: (Farsightedness)
Image focused behind retina
What are the three main areas of the ear?
External ear: (hearing). Terminates at eardrum
(tympanic membrane). Includes auricle and external auditory meatus
Middle ear: (hearing). Air-filled space containing auditory ossicles
Inner ear: (hearing and balance). Interconnecting fluid-filled tunnels and chambers within the temporal bone