chapter 9 Flashcards
homeostasis
condition in which all of the body’s systems are balanced and are working together to maintain internal stability, when body systems are working at their best
metabolism
for homeostasis to occur, the physical and chemical processes, that must be working at a steady level, when dz or injury occurs, body’s metabolism is disrupted and homeostasis is lost
body systems
integumentary, musculoskeletal, nervous, circulatory, respiratory, urinary, gastrointestinal, endocrine, reproductive, immune/lymphatic
organs
each has a specific function; cells (building blocks of body) - tissues (group of cells that perform a similar task) - organs (have specific function)- body systems
integumentary system
largest organ and system in body is the skin, functions are to protect internal organs from injury, protect body against bacteria, and prevent loss of too much water, also responds to heat, cold, pain, touch, and pressure, and regulates body temperature
dilate
when blood vessels widen when outside temp is too high, which brings more blood to the surface to cool it off
constrict
when blood vessels narrow, when outside temp is too cold, to restrict amt of blood reaching skin, so the blood vessels help body retain heat
dermis of skin
contains capillaries, nerves, sweat glands, sebaceous glands, and hair roots, where hair grows from
epidermis of skin
has no blood vessels and only a few nerve endings, contains both dead and living cells, contains pigment cells that give skin its color
musculoskeletal system
made up of muscles, bones, ligaments, tendons, and cartilage, functions: to give body shape and structure, to allow body to move, to protect body organs, to maintain posture, and to produce heat
muscle atrophy
when muscle wastes away, decreases in size,a nd becomes weak
muscle contracture
when muscle or tendon shortens, becomes inflexible, and freezes in position
CNS
central nervous system, which is composed of brain and spinal cord
PNS
peripheral nervous system, deals with periphery of the body via the nerves that extend throughout the body
CSF
cerebrospinal fluid, fluid that circulates around brain and spinal cord to provide a cushion against injury
brain
has 3 main sections, cerebrum, cerebellum, and brainstem, with outer layer of cerebrum is cerebral cortex
cerebral cortex
part of brain in which thinking, analysis, association of ideas, judgment, emotions, and memory occur. also directs speech and emotions, interprets messages from eyes ears nose tongue skin and controls voluntary muscle movement
cerebrum
divided into right and left hemispheres
right hemisphere
controls movement and function in left side of the body so any illness/injury to right hemisphere affects left side
left hemisphere
controls movement and function in the right side of the body so any illness/injury to left hemisphere affects right side
cerebellum
controls balance and regulates body’s voluntary muscles, produces and coordinates smooth movements,
brainstem
connects the cerebrum and cerebellum to spinal cord, is a regulatory center, controls HR, breathing, swallowing, coughing, vomiting, and closing/opening of blood vessels
nervous system
functions are to control and coordinate all body functions and to sense, interpret, and respond to changes occurring both inside and outside human body
sense organs
eyes, ears, nose, tongue, skin, part of CNS bc they contain receptors that receive impulses from environment that they relate impulses to nerves
sclera
outer part of eye, appears white except in front where it is called the cornea
cornea
clear outer layer of eye, but appears colored bc it lies over the iris
iris
colored part of eye
pupil
black circle in center of iris that widens or narrows to adjust the amt of light that enters the eye
retina
at back of eye that contains cells that respond to light and send a message to the brain where the picture is interpreted so a person can see
ear
provides balance and hearing, divided into 3 parts, outer middle and inner ear
outer ear
funnel-shaped part called auricle or pinna that guides sound waves into auditory canal,
auditory canal
contains many glands that secrete earwax
eardrum
aka tympanic membrane, separates outer ear from middle ear
middle ear
consists of eustachian tube and three ossicles, small bones that amplify sound