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
What is the name of the membrane of the external ear that vibrates during sound? Describe it.
Tympanic membrane
Sound waves cause it to vibrate
Border between external and middle ear
What are the names of the three bones found in the middle ear?
Auditory Ossicles: Malleus, incus, stapes
Name the three areas of the ear where we find bony labyrinth.
Cochlea: hearing
Vestibule: balance
Semicircular canals: balance
Describe two of the qualities of sound
Volume or amplitude: function of wave amplitude
Pitch: function of wave frequency
Describe how sound travels through your ear.
- Sound waves strike the tympanic membrane and cause it to vibrate.
- Sound waves strike the tympanic membrane and cause it to vibrate.
- The foot plate of the stapes vibrates in the oval window.
- The vibrations of the oval window causes a vibration through the cochlea and vibrates the perilymph.
What are the two muscles of the middle ear that move the ossicles?
Tensor tympani: inserts on malleus
Stapedius: inserts on stapes
What are the two subgroups of the Peripheral Nerves?
Sensory Neurons- Carry AP from the periphery to the CNS
Motor Neurons- Carry AP from the CNS to effector organs.
Sensory neurons carry info up the hill. Motor Neurons carry info down the hill.
What are the two types of motor neurons?
Somatic Motor Neurons - Supply information to the skeletal muscles.
Autonomic Motor Neurons - Supply infornation to the smooth/cardiac muscle.
Describe the cell bodies of Somatic Motor Neurons
These cell bodies are located in the CNS.
Their axons extend from CNS to skeletal muscle and the tails of the axon can sometimes be quite long.
Controlled consciously most of the times.
Describe the cell bodies of Autonomic Motor Neurons
Contain 2 Neurons. 1-preganglionic 2- postganglionic
Body of 1st neuron in CNS body of 2nd neuron in autonomic ganglia.
Synapse within the autonomic ganglia.
Unconcious control.
What is a gland?
Organ of secretion
What is a exocrine gland?
Glands that secrete substances onto the bodies external surface
What is an endocrine gland?
Glands that secrete chemical signals or hormones into the circulatory system.
What is a hormone?
Type of intercellular signal, between cells, that are produced by endocrine glands, enter circulatory system and affect distant cells.
What is Autocrine?
Released by cells and have an affect only on the same cell type from which the chemical signal was released.
What is Paracrine?
Released by cells and affect other cell types locally. Does not get transported through blood.
What is Pheromones?
Secreted into environment and modify behaviior and physiology of the other organism.
What are neurohormones?
Produced by neurons and function like hormones.
Describe positive feedback?
When the body increases the deviation from the norm.
Describe negative feedback?
When the body works against positive feedback to keep the body at homeostasis
What is the function of the endocrine system?
Responsible for maintaining homeostasis via precise regulation.
What is the function of the pituitary gland?
Regulates many body functions and other endocrine glands.
Where is the pituitary gland located?
Beneath the hypothalumus of the brain in the skull bone indentation called Stella Turcica which forms a nest to protect the gland.
What are the two areas of the pituitary gland?
Posterior Pituitary: Extention of the hypothalumus, produces neurohormones.
Anterior Pituitary: Produces endocrine hormones. Contains glandular tissue.
What is the name of the structure that connects the Hypothalumus and the Posterior Pituitaty? How does it function?
Hypothalamo-Hypophysial Tract
Nerve cells are produced by the hypothalumus, they are sent through the posterior pituitary via the HHT and then they are released into the bloodstream.
What is the name of the structure that connects the hypothalumus to the anterior pituitary gland? How does it function?
Hypothalamo-hypophysial Portal System
Neurohormones are produced by Hypothalumus and decend through portal system. They enter anterior pituitary and leave the capillaries and enter the endocrine glands and tell them to produce certain hormones.
What hormones are produced by the Posterior Pituitary?
Antidiuretic Hormone (ADH) - Prevents the output of large amounts of urine.
Oxytocin: Stimulates smooth muscle fibers in the uterus for childbirth and promotes ejection of milk during lactation.
How does the thyroid gland function to produce T3/T4?
First the follicular cells produce thyrogobulin and fills the follicle.
Then Iodine enters the cell from the outside.
Iodine then binds with the component of the thyrogobulin called tyrosine.
This binding causes T3/T4
What are the symptoms of hyperthyroidism or the overproduction of T3/T4?
Increase metabolic rate
Increase blood pressure/heart rate
Increase appetite/weight loss
What hormone does the parathyroid secrete?
PTH- parathyroid hormone.
This inreases calcium levels in the blood by promoting calcium reabsorbtion.
Describe the composition of the adrenal gland
Found on the superior poles of the kidneys.
Has two sections: Cortex - outer layer, Medulla - inner layer.
What does the adrenal medulla secrete?
Secretes the neurohormone epinephrine and norepinephrine.
What hormone is produced by the Zona glomerulosa layer of the adrenal cortex?
Mineralocorticoids: increase the rate of sodium reabsorption by the kidneys.
What hormone is produced by the Zona fasciculata layer of the adrenal cortex?
Glucocorticoids: increases fat and protein breakdown.
What hormone is produced by the Zona reticularis layer of the adrenal cortex?
Androgens: Stimulate pubic and axillary hair growth.
Describe the structure and function of the pancreas
Located along the small instestine and stomach.
Has a dual function as both an endocrine and exocrine gland.
How is the pancreas an exocrine gland?
It secretes digestive juices into the small intestine to break down food that did not fully digest in the stomach.