Lab 11 Flashcards
Scattered throughout the body that include the somatic senses - touch, pressure, pain, temperature and proprioception and the visceral senses, which provide information about internal organs
General sesnses
Vision, hearing, equilibrium, taste and smell have distinct receptor cells that are restricted to the head and are localized in complex sensory structures (eye and ear) or in distinct epithelial structures (taste buds and olfactory epithelium)
Special senses
Functions as padding and insulation within the orbit to protect the eye
Adipose tissue
“White of the eye”
Protects and shapes the eyeball and provides a sturdy anchoring site
Sclera
Transparent, anterior portion of the sclera
Allows light to enter the eye and it helps bend (refract) light rays so they are focused on the photoreceptors in the retina
Cornea
Solid white cord of sensory nerve fibers
Optic Nerve III
Skeletal muscles provide rotary movements of the eye, focus the eye for optimum vision and anchor the eye in the bony orbit
Appear as flat bands on the surface of the eye
Extrinsic eye muscles
Found in front of lens between lens and cornea (anterior cavity)
Aqueous humor
Forms a fluid cushion, retain eye shape, provides a root for nutrient an waste transport
Aqueous humor
Outermost layer of the eye
Sclera and Cornea
Middle layer of the eye includes:
Iris, ciliary body, choroid
The coloured, circular portion of the eye that lies anterior to the lens
Consists of two layers of muscles - inner circular and outer radial smooth muscles
Iris
Inner circular and outer radial smooth muscles arranged around a central opening called the:
Pupil
In close vision and bright light, the circular smooth muscles of the iris _______ and the pupil becomes _______, as a result, less light enters the eye
Contract: constricted
In distant vision and dim light, the radial smooth muscles _______ and the pupil _______, allowing more light to enter the eye
Contract; dilates
Is normally flexible and changes shape to focus light rays for close and far vision
Crystalline lens
The lens is held in place by _______ _______ which are attached to the ciliary body
Suspensory ligaments
Is attached to the iris posteriorly and is made up of ciliary processes and ciliary muscles
Ciliary body
Control the shape of the lens
Ciliary muscles
Contain capillaries that produce the aqueous humor
Ciliary processes
Continuous with the ciliary body and extends around the posterior of the eye
Highly vascular and darkly pigmented tissue
Functions to absorb excess light rays to prevent reflection and scattering of light within the eyeball
Choroid
Choroid has an iridescent portion (“rainbow”, in sheep) that enhances night vision by reflecting light back onto the:
Retina
Forms the innermost layer of the eye, is very thin and easily separated from the choroid
Very thin yellow layer which most likely has fallen inwards onto the vitreous body/humor
Held in position up against the choroid by the vitreous body in the intact eye
Retina
The retina consists of two layers:
Outer pigmented layer (next to the choroid)
Inner neural layer
The neural layer is composed of three main types of neurons:
Photoreceptors
Bipolar cells
Ganglion cells
Photoreceptor cells, the rods and cones convert light energy into signals that are sent to the bipolar cells and then back to the ganglion cells where the ______ _____ are generated
Action Potentials
The ganglion cell axons leave the back of the eye as the
Optic nerve
The percentage of total blood volume occupied by RBCs is called the _______ and this value is about 45%.
Hematocrit
The hematocrit is determined by centrifuging a sample of _______ blood.
Heparinized
Heparin prevents:
Clotting of blood
The heavier formed elements are packed down by centrifugal force and the less dense plasma remains at the:
top
The hematocrit can vary in healthy individuals. For males, the value is _______ while in females it is ______.
40-54%; 38-46%
Leukocytes and platelets contribute less than ____ of blood volume.
1%
Plasma makes up most of the remaining ____ of whole blood.
55%
Uses a series of lithographed colors that lustrate the tints of blood ranging from 10% to 100% hemoglobin concentration The scale us accompanied by a booklet containing tear-away sheets of prepared paper. A sample of blood is placed of the paper and the color of the blood is matched with the appropriate standard color of the scale.
Tallquist Scale
An instrument which compares hemoyzed sample of blood wth a color standard by moving a slide on the __________ back and forth until the”two halves of the green field match, A numerical value in grams Hb/100 mi of blood is attained on the upbe host scale by the index mark on the slide.
Hemoglobinometer
Are located on the RBC surface
Antigens
Are located in the blood plasma
Antibodies
The term Rh positive (Rh*) signifies the presence of ________ in the blood. Rh positive individuals carry ________ in their blood and do not form antibodies against the antigen.
antigen D
The individuals in the population that do not have antigen D present in their blood are termed _________. These individuals will form antibodies against antigen D if it is introduced into their blood and agglutination of the red blood cells can occur.
Rh negative
The Rh system differs from the ABO blood group system in that there are no ______ occurring antibodies are present in the plasma.
Natrually
An abnormally low red blood cell count, for example, could furnish evidence that indicates _______. Signifies a decreased amount of hemoglobin in the blood and consequently a decreased amount of oxygen will reach the tissues. Could result from a decreased production of erythrocytes if deficiencies in iron or Vitamin B12 occurred or if certain types of malignancies were present. May also be caused by increased destruction or malformation of red blood cells as might occur in cases of severe infections, sickle cell anemia or incorrect transfusions.
Anemia
The hematocrit and hemoglobin evaluations are the most important tests in the diagnosis of _______
Anemia
A condition characterized by above normal red blood cell counts, may be due to living at high altitudes or red marrow malignancy.
Polycythemia
A tool used for manual cell counting. As the name implies it was originally invented for quantifying blood cells.
A hemocytometer (also known as a haemocytometer or a cell counting chamber)
In healthy individuals, the white blood cell count ranges between ______ and _______ white blood cells per cubic millimeter of blood.
5,000 and 10,000
A white cell count of more than 10,000 is called ________.
Leukocytosis
A white blood cell count significantly less than 5,000 is termed _________.
Leukopenia
______ conduct blood away from the heart and ______ conduct blood towards the heart
Arteries; veins
Interconnecting the two major blood vessel types are microscopic _______. Consist of only a single layer of endothelial cells (simple squamous cells) and a basement membrane. The exchange of materials between the circulatory system and the tissues only occurs through these thin walled _______.
Capillaries
Three structural layers (tunics) make up the wall of an artery and vein:
Tunica Interna
Tunica Media
Tunica Externa
The innermost layer, composed of a single layer of endothelial cells. In some of the large arteries this layer also includes an internal elastic membrane (known as the
elastica interna) which appears as a thin, bright, scalloped line.
Tunica interna (intima)
The middle layer, consisting mainly of smooth muscle and elastic fibers running in a circular direction around the lumen.
Tunica media
The outer layer, composed of fibrous connective tissue and fat cells. In some of the larger arteries the tunica media and tunica externa are separated by an external elastic membrane, the elastica externa.
Tunica externa (adventitia)
Consists of a layer of endothelial cells. There is no elastica interna.
Veins - Tunica Interna
Composed mainly of circular smooth muscle cells.
Veins - Tunica Media
Composed of loose fibrous connective tissue with fat cells.
Veins - Tunica Externa
The upper two chambers are the ______. The lower two chambers are the ______.
atria; ventricles
The ______ are the thin-walled receiving chambers for blood returning to the heart from veins
Atria
Are the pumping chambers and have a very thick muscular wall.
Ventricles
A slight groove containing _______ _______ ______ separates the left and right ventricles externally on the ventral surface.
Coronary Blood Vessels
The cardiac muscle of the heart wall requires its own separate coronary circulation as blood within the heart chambers cannot adequately supply oxygen and nutrients to the thick _______.
Myocadium
The coronary veins drain blood from the capillaries and return the blood to the _______ _____, a large vein that also opens into the right atrium.
Coronary sinus
This large artery originates from the right ventricle of the heart and is the start of the pulmonary circuit of blood flow.
Pulmonary Trunk
Does the pulmonary artery carry oxygenated or deoxygenated blood?
Deoxygenated
The artery which carries oxygenated blood from the left ventricle into the systemic circulation
Aorta
The large vein which dellvers venous blood collected from the head, neck and arm regions to the right atrium.
Superior Vena Cava
The large vein which delivers venous blood collected from the lower body regions to the right atrium.
Inferior Vena Cava
These veins are visible on the dorsal surface of the heart. These blood vessels carry oxygenated blood from the lungs to the left atrium of the heart.
Pulmonary Veins
Receives blood from the systemic circulation through the superior vena cava, inferior vena cava, and the coronary sinus
Right atrium
Carries blood collected from the head, neck and arms
Superior vena cava
Returns blood from the myocardium.
Coronary sinus
Venous blood passes from the right atrium
into the:
Right ventricle
From the right ventricle, it is pumped to the lungs by way of the
Pulmonary trunk
The pulmonary trunk leaves the anterior end of the right ventricle and curves dorsally. The pulmonary trunk splits into two smaller arteries, the left and right ______ _______, which continue to the lungs.
Pulmonary arteries
After gas exchange in the lungs occurs, blood rich in oxygen returns to the _____ _____, through the pulmonary veins.
Left atrium
Blood next enters the left ventricle, which pumps it through the:
Aorta (to body)
The major circulatory pathways of the body are:
Pulmonary circulation
Systemic circulation
Composed or the arteries and veins that transport blood from the heart to the lungs and back to the heart
Pulmonary circulation
Transports oxygenated blood to all parts or the body that are not in the pulmonary circuit and returns deoxygenated blood to the heart
Systemic circulation
Where the optic nerve leaves the retina
“Blind spot”
Optic disc
Lateral to the optic disc is a small yellowish area on the retina
Macula lutea
The central portion of the macula lutea has a small depression
Fovea centralis
The lens of the eye must become more rounded or convex in shape in order to view objects at close range. This adjustment is called:
Accommodation
The closest distance at which an object appears to be in sharp focus is called
Near point
Refers to the degree of “sharpness” of eyesight
Visual acuity
Determines the smallest standard-sized printed letter of the alphabet that can be clearly seen by an individual at a distance of 20 feet
Snellen Test
A person with normal vision is defined as one who can read standard-sized letters at a distance of 20 feet and is recorded as a fraction 20/20
Normal visual acuity
Hyperopia is corrected with a:
Converging lens
Myopia is corrected with a:
Diverging lens
The cornea or lens has irregularities in the surface curvature, this condition is known as:
Astigmatism
The ear is divided into 3 main regions:
External ear, middle ear, internal ear
Collects sound waves and channels them inwards
External ear
Transfers sound vibrations to the oval window
Middle ear
Contains receptors for hearing and equilibrium
Internal ear
The external ear consists of two parts:
Auricle (pinna)
External auditory canal (meatus)
The flap of skin and elastic cartilage fixed to the side of the head
Pinna
Collects sound waves and channels inwards
Pinna
Passageway that leads into the head from the auricle.
Functions to conduct airborne sound waves picked up by the auricle to the tympanic membrane.
External auditory canal
External auditory canal contains special glands called:
Ceruminous glands
Secretion from ceruminous glands and its function:
Cerumen (wax), prevents insects from entering ear canal
Division of the ear is a small air-filled chamber hollowed out of the _________ bone
Temporal bone
Chain of 3 bones or ossicles that connect the middle ear with the inner ear:
Malleus (hammer)
Incus (anvil)
Sapes (stirrup)
The Malleus contacts the tympanic membrane while the stapes fits snugly into the _____ ______ of the inner ear
Oval window
Vibrations of the tympanic membrane are transferred and magnified by the ossicles to cause ______ at the oval window
Vibrations
The anterior wall of the middle ear contains the opening of the __________ tube or ________ tube
The structure connects the middle ear with the pharynx.
Function: equalizes pressure across the two cavities.
Auditory (pharyngotympanic) tube; eustachian tube
The internal ear consists of two main divisions:
Outer bony labyrinth
Inner membranous labyrinth
A system of chambers within the temporal bone of the skull which contains perilymph fluid
Bony labyrinth
3 layers of the outer bony labyrinth include:
Cochlea
Vestibule
Semicircular canals
Lies within the bony labyrinth and consists of interconnecting sacs and ducts filled with endolymph fluid
Membranous labyrinth
Structures of the membranous labyrinth:
Cochlear duct
Saccule and utricle
Semicircular ducts
Receptors for hearing are located within the:
Cochlear duct
The receptors for equilibrium are located with the:
Saccule
Utricle
Semicircular ducts
Spiral, bony chamber that resembles a snail’s shell
Cochlea
Running through the center of the cochlea is the part of the membranous labyrinth known as:
Cochlear duct
The cochlear duct contains the _______________, the receptor organ for hearing.
Organ of Corti
Special receptors, _________, located in the organ of corti are designed to convert sound waves into nervous impulses that are carried by the cochlear branch of the vestibulocochlear nerve VIII to the auditory area of the cerebral cortex.
Hair cells
Note the cochlear duct in the presence of the organ of corti which contained the hearing receptor cells (hair cells) between the _________ and ________ membranes
Tectorial and basilar
______________ sensations provide information about the position of the head in space by monitoring gravity, linear acceleration, and rotation.
Equilibrium
The sense of equilibrium has two components _______ and _______ equilibrium
Static and dynamic equilibrium
Vestibule is an egg-shaped cavity of the Bony labyrinth that contains 2 saclike chambers of the membraneous labyrinth:
Saccule and utricle
The receptors involved in maintaining ________ equilibrium are located here these receptors evaluate the position of the head in space with respect to gravity.
Static equilibrium
(Static equilibrium) They also respond to linear acceleration forces, that is, ___________ line changes in speed and direction of movement.
Straight
The utricle and saccule each contains sensory hair cells that have cytoplasmic processes which extend into the cavity of the _________ labyrinth
Membranous
The hair cell processes are embedded in a gelatinous layer which consists contains particles of calcium carbonate, called:
Otoliths
When the head tips downward, the otoliths slide with gravity in a downward pull on the gelatinous mass which, intern, exerts a downward pull on the process is of the hair cells and makes them:
Bend
The movement of the process stimulates the _________ at the base of the hair cells.
Dendrites
The impulses then transmitted to the brain through the vestibular branch of the:
Vestibulocochlear nerve VIII.
The three semicircular canals which contain the membraneous then semicircular ducts arranged at right angles to each other in three planes:
Anterior duct
Posterior duct
Lateral duct
The receptors involved in maintaining ___________ equilibrium are located within the ducts.
Dynamic
These receptors evaluate the position of the head in response to angular _________ movements of the head.
Rotational
DYNAMIC: Due to the orientation of the ducts, movement of the head and body can be detected in ______ dimensions of space.
ALL
The ampulla is the dilated portion of each duct which has a small elevation called the:
Crista
Each crista is composed of a group of hair cells covered by a mass of gelatinous material called the:
Cupula
When the head moves, the endolymph inside the semi circular duct flows over the hair cell processes and _______ them
Bends
The movement of the hair cell processes stimulate ________ neurons, and the impulses pass over the vestibular branch of the vestibulococlear nerve.
Sensory
The impulses then reached the brain where they are integrated with inputs from ________ receptors and proprioceptors
Visual
Commands are then sent to motor centres that control the:
Extrinsic eye muscles
Neck, limb and trunk muscles
The muscle movements that occur allow one to remain focused on the visual field and adjust ones body position to maintain or regain _______
Balance
Loss of hearing may result from a failure to conduct sound waves and vibrations from the outer to inner ear and middle ear deafness, also called:
Conduction deafness
Conduction deafness may be due to damage to the:
Tympanic membrane OR
Auditory ossicles
Hearing loss may also be due to a neurological failure such as damage to the hair cells of the cochlea, to the cochlear nerve or to the neural pathway that transmit and transmits nerve impulses from the vestibulocochlear nerve to the primary auditory cortex in the temporal lobe.
Sensorineural deafness
is a screening test for hearing performed with a tuning fork. It can detect unilateral (one-sided) conductive hearing loss (middle ear hearing loss) and unilateral sensorineural hearing loss (inner ear hearing loss).
The Weber test
is used to evaluate hearing loss in one ear. Differentiates sound transmitted through air conduction from those transmitted through bone conduction via the mastoid bone. By comparing air and bone conduction, it helps detect conductive hearing loss in one ear.
The Rinne test
Weber test - if sound is louder in the right ear, this indicates _________ deafness in the right ear or _________ deafness in the left ear.
Conduction; sensioneural
When a cold swab is placed in an ear, it increases the density of the fluid and the lymph inside the semicircular ducts. This increase in the density of the endolymph stimulates the hair cells within the semicircular ducts causing a sensation of rotation called _________
Nystagmus
Five primary or basic tastes are present in humans:
Sweet, sour, bitter, salt, and umami.
______ taste is elicited by many organic substances such as sugars, alcohols and some amino acids.
Sweet
______ taste are produced by hydrogen ions is found in the citric acid of lemon juice.
Sour
______ foods taste salty due to the presence of metal ion such as sodium and potassium.
Salty
______ flavours are often due to nitrogen containing compounds such as caffeine, quinine and nicotine. Umami is described as a meaty or savoury taste produced by glutamate or other amino acids.
Bitter
Taste buds generally respond to a mixture of the _____ basic tastes
Five
