STM 010. 2nd Achievement

sensory receptors

are dendrites of sensory neurons specialized for receiving specific kinds of stimuli

unencapsulated

• free or naked

• nerve endings are dendrites whose terminal ends have little or no physical specialization

encapsulated nerve endings

are dendrites whose terminal ends are enclosed in a capsule of connective tissue

exteroceptors

• occur at or near the surface of the skin and are sensitive to stimuli occurring outside or on the surface of the body

• include touch, pain, temperature, vision, hearing, smell, and taste

interoceptors

respond to stimuli occurring it he body from visceral organs and blood vessels

proprioceptors

respond to stimuli occurring in skeletal muscles, tendons, ligaments, and joints

mechanoreceptors

respond to physical force such as pressure and stretch

photoreceptors

respond to light

thermoreceptors

respond to temperature changes

chemoreceptors

respond to dissolved chemicals

nociceptors

respond to tissue damage (injury); the brain interprets the pain

sclera

tough outer coat ; “white” of the eye

choroid

pigmented vascular layer prevents scattering of light

retina

innermost layer of the eye

conjunctiva

mucous membrane covering the front surface of the sclera and also lines the eyelid

lens

transparent body behind the pupil

external ear

• auricle (pinna)

• curving canal 2.5 cm ; 1 inch in length

• contains ceruminous glands

• ends at the tympanic membrane

middle ear

• houses ear ossicles - malleus, incus, stapes

• ends in the oval window

• the auditory tube connects the mid ear to the throat

• inflammation called otitis media

inner ear

• bony labyrinth filled with perilymph

• the receptors for balance

• specialized hair cells on the organ of corti respond when bent by the movement

deafness

is a partial or total loss of hearing

labyrinthine disease

is a term applied to disorders of the inner ear that produce symptoms of dizziness, nausea, ringing in the ears, and hearing loss

motion sickness

functional disorder that is characterized by nausea caused by angular and vertical motion

otitis media

is an acute infection of the tympanic cavity

astigmatism

is the unequal focusing of light on the retina, which causes part of an image to appear blurred

blindness

• is partial loss or lack of vision

• caused by a number of disorders such as cataract, glaucoma, and detachment or deterioration of the retina

cataract

• cloudiness or opacity of the lens, which impairs or prevents vision

• common in older people and is the leading cause to blindness

color blindness

inability to perceive certain colors or, more rarely, all colors ; red-green color blindness is the most common type

conjunctivitis

• inflammation of the conjunctiva

• caused by allergic reactions, physical or chemical causes, or infections

farsighted

is a blurred vision cause by light rays being incorrectly focused behind the retina

glaucoma

is a condition in which aqueous humor is produced more rapidly than it is removed

nearsighted

is blurred vision caused by light rays being incorrectly focused in front of the retina

retinoblastoma

is a cancer of immature retinal cells

strabismus

a disorder of the extrinsic eye muscles in which the eyes are not directed toward the same object simultaneously

anosmia

loss of sense of smell

ageusia

loss of sense of taste

hyposmia

reduced ability to smell

hypogeusia

reduced ability to taste sweet, sour, bitter, or salty things

endocrine system

Second messenger system of the body

steroids

made from cholesterol

prostaglandis

made from highly active lipid

endocrine glands

are activated by other hormones

humoral stimuli

Changing blood levels of certain ions stimulate hormone release

pituitary gland

• Size of a grape

• Hangs by a stalk from the hypothalamus

• Protected by the sphenoid bo

prolactin

• Stimulates and maintains milk production following childbirth

• Function in males is unknown

andrenocorticotropic hormone

• Regulates endocrine activity of the adrenal

cortex

thyroid stimulating hormone

• Influences growth and activity of the thyroid

growth hormone

• Causes amino acids to be built into proteins

• Causes fats to be broken down for a source of energ

gonadotropic hormones

• Regulate hormonal activity of the gonads

luteinizing hormone

• Triggers ovulation

• Causes ruptured follicle to become the corpus luteum

• Stimulates testosterone production in males

oxytocin

• Stimulates contractions of the uterus during labor

• Causes milk ejection

antidiuretic hormone

• Can inhibit urine production

• In large amounts, causes vasoconstriction leading to increased blood pressure (vasopressin)

thyroid gland

• Found at the base of the throat

• Consists of two lobes and a connecting

isthmus

thyroxine

secreted by thyroid follicles

triiodotyronine

conversion of T4 at target tissues

calcitonin

• Decreases blood calcium levels by causing its deposition on bone

parathyroid gland

• Tiny masses on the posterior of the

thyroid

• Secrete parathyroid hormone

mineralocorticoids

• Produced in outer adrenal cortex

• Regulate mineral content in blood, water,

and electrolyte balance

• Target organ is the kidney

glucocorticoids

• Produced in the middle layer of the adrenal cortex

• Promote normal cell metabol

sex hormones

Produced in the inner layer of the adrenal

cortex

insulin

allows glucose to cross plasma membranes into cells from beta cells

glucagon

allows glucose to enter the blood from alpha cells

pineal gland

Found on the third ventricle of the brain

thymus

• Located posterior to the sternum

estrogen

• Produced by Graafian follicles or the placenta

• Stimulates the development of secondary

female characteristics

• Matures female reproductive organs

progesterone

• Produced by the corpus luteum

• Acts with estrogen to bring about the menstrual cycle

• Helps in the implantation of an embryo in the uterus

blood plasma

• blood minus its cells

• water containing many dissolved substances

• varies with size and sex; 4 to 6 liters about average; about 7% to 9% of bodyweight

granular leukocytes

neutrophils, eosinophils, and basophils

nongranular leokocytes

lymphocytes and monocytes

RBCs

4.5 to 5 million per mm' of blood

WBCs

5,000 to 10,000 per mm' of blood

platelets

300,000 per mm' of blood

RBCs (erythrocytes)

• disk shaped, without nuclei

• transports oxygen and carbon dioxide

hematocrit test

medical test in which a centrifuge is used to separate whole blood into formed elements and liquid fraction

WBCs (leukocytes)

defense

leukopenia

abnormal low WBC count

leukocytosis

abnormal high WBC count

platelets

play an essential role in blood clotting

antigen

substance that can activate immune system; present on the surface

antibody

substance made by body in response to stimulation by an antigen

TYPE A

anti-B type antibodies in plasma

TYPE B

anti-A type antibodies in plasma

TYPE AB

type A and type B self antigens; no anti-A or anti-B antibodies in plasma

TYPE O

no type-A and type-B antigens; both anti-A and anti-B antibodies in plasma

rh system

this term is used because this important blood cell antigen was first discovered in the blood of rhesus monkeys

Rh-positive blood

rh factor antigen present in RBCs

Rh-negative blood

no Rh factor present in RBCs

type o rh negative

universal donor blood

type ab rh negative

universal recepient blood

anemia

the decreased oxygen carrying capacity of the blood, and it is the most common blood disorder

erythroblastosis fetalis

results from anti rh antibodies produced by a previously sensitized rh woman carrying an rh+ fetus

polycythemia

is a condition characterized by an excess of erythrocytes in the blood

leukemia

is the group of cancers in the red bone marrow cells that forms WBCs

hemophilia

is a group of inherited diseases that occurs almost always in the males because they are sex-linked disorders

thrombocytopenia

is a condition in which the number of platelets is so low that spontaneous bleeding cannot be prevented

thrombosis

the condition resulting from the formation of a blood clot in an unbroken blood vessel

atria

upper chambers and receiving chambers

ventricles

lower chambers and discharging chambers

myocardium

wall of each heart chamber is composed of cardiac muscle tissue

endocardium

smooth lining of heart chambers

endocarditis

inflammation of endocardium