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Body Systems

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epithelial tissue
sheets of cells that cover the body's suface and form the lining of the internal organs
connective tissue
hold together and support other tissues and cushion, insulate, and connect organs
nervous system
the system that forms the communication system that helps the body respond to the enviroment
neuron
a nerve cell that transmits signals
epidermis
the outermost layer of skin made of mostly dead epitheliat cells that flake off
melanin
a pigmented protein that fives the skin color
dermis
the layer of skin that lies beneath and supports the epidermis
skeletal muscle
a voluntary muscle connected to bone
smooth muscle
an involuntary muscle found on most organs
cardiac muscle
an involuntary muscle that helps your heart pump blood
homeostasis
the internal stability maintained by the body
joint
an area where one bone meets another
ligament
a strong fibrous tissue in a joint, attatching bone to bone
tendon
dense tissue attatching bone to muscle
hormone
signal molecules released by glands to help regulate the body systems
interstitial fluid
aqueous solution filling space between cells in a tissue
alimentary canal
the tube in which digestion occurs starting at the mouth and ending at the anus
bolus
a chewed clump of food that travels the alimentary canal
peristalsis
a series of muscle contractions that push through the esophogus
chyme
acidic mixture of food and stomach fluids that travel from the stomach to the small intestine
villi
small fingerlike projections in the wall of the small intestine that absorb nutrients
arteries
blood vessels carrying blood away from the heart
capillaries
microscopic blood vessels connecting arteries and veins allowing exchange between blood and interstitial fluid
veins
blood vessels carrying blood to the heart
lymph
fluid from blood lost to interstitial fluid that is collected in the lymphatic vessels and reused in blood
aorta
the artery that supplies oxygen rich blood to the body; on left side of the heart
pulmonary circuit
carry blood from the heart to the lungs to collect oxygen and back to the heart to be dispersed through the body
systemic circuit
carry oxygen rich blood from the heart, to the body and back to the heart
plasma
solution in blood containing water, salts, and proteins
hemoglobin
a protein in red blood cells that stores oxygen
platelet
small fragments of blood cells that stick to a damaged blood cells and release clotting factors to form fibrin and trap red blood cells from leaving vessels
pharynx
the throat; passage ways for air and food cross
epiglottis
covers air passage when swallowing to prevent water and food from entering lungs
trachea
the air passageway to the lungs
diaphragm
sheet of muscle forming the bottom wall of the chest cavity allowing breathing
pathogens
disease causing organisms or viruses
germ theory of disease
a theory stating that infectious disease is caused by pathogens that spread among organisms
histamine
chemical alarm released by mast cells which causes blood vessels to increase blood flow and the number of white blood cells there
antigen
a molecule on the surface of cancer cells, pollen, fungi, bacteria, and viruses that provokes an immune response
antibodies
proteins found on the surface of white blood cells that attck certain antigens
vaccine
a nonharmful does of a pathogen to stimulate immune response and formation of memory cells to protect from a real exposure to the pathogen
active immunity
when the body produces antibodies against infection
passive immunity
when the body recieves antibodies for a disease from another source
allergies
an abnormal oversensitivity to an otherwise nonharmful antigen known as an allergen
urea
compound of ammonia and carbon dioxide excreted from the body by the kidneys
excretion
the removal of nitrogen-containing wastes from the body
endocrine glands
glands that secret hormones
nephrons
microscopic filtering tubules in the kidney consisting of one tubule and its blood vessels
nervous
the system that coordinates the body's activities by detecting stimulii and directing the body's responses
skeletal
the system that provides body support, protects certain organs such as the brain and lungs, and works with the muscular system in body movements
muscular
the system that enables body movement and facial expressions essentail to human communication
integumentary
the system that covers the body and protects it from injury, infection, excessive heat/cold, and drying out
circulatory
the system that delivers oxygen and nutrients to body cells and transports waste products to excretory organs
respiratory
the system that exhchanges gases with the environment
digestive
the system that ingests food, breaks it down into smaller chamical units for use in the body and eliminates undigested material
excretory
the system that removes waste products from the body and regulates the chemical makeup of the blood
endocrine
the system that secretes hormones that affect the functons of target cells and thereby regulates the activites of the other organ systems
reproductive
the system that reproduces gametes; the female system also provides the organs needed to support a developing embyro
lymphatic/immune
the system that defends the body against infections and cancer cells; supports the function of the circulatory sustem by returning fluid to blood vessels near heart
keratin
protein that makes up hair and nails
central nervous system
the part of the nervous system that includes the brain and spinal chord
peripheral nervous system
the part of the nervous system that includes nerves
sensory receptors
the part of the nervous system that includes the nose, mouth, eyes, ears, and skin
nose/mouth> pharynx> trachea> lungs
the order of the respiratory system
rectum and anus
organs of elimination
ingestion
taking food in
digestion
machanically and chemically breaking down food
absorbtion
cells take up nutrients
elimination
removal of undigested material
pharynx
the part of digestion where the bolus goes before the throat
epiglottis
prevents food from entering the trachea
esophagus
the part of digestion that moves the bolus to the stomach through peristalsis
gastric juice
mixture of mucus, hydrochloric acid and enzymes that breaks down food
small intestine
the part of digestion where digestion is completed and absortion begins
liver
makes bile to separate fat
gallbladder
stores bile and releases it into the small intestine to mix with chyme
pancreas
releases juices into the small intestine that contain enzymes for breaking down carbs, proteins, and lipids
large intestine
reabsorbs water from undigested matieral
pineal
the gland that controls biorhythms in some animals and control the onset of puberty in humans
thyroid
the gland that stimulates metabolic rate and is essential to normal growth and development
pituitary
the gland that stimulates growth and stimulates secretion of hormones from other glands
ovary
the gland that stimulates development of female secondary sex characteristics, stimulates growth of sex organs at puberty, and prompts monthly preparation of uterus for pregnancy
hypothalamus
the gland that the major area where the nervous and endocrine systems interact
pancreas
the gland that controls blood glucose levels and determines the fate of glycogen
adrenal
the gland that initiates stress responses, increases heart rate, blood pressure, and metabolic rate, dilates blood vessels, mobilizes fat and raises blood sugar levels
thymus
the gland that promotes production and maturation of white blood cells
testis
the gland that stimulates development of male secondary sex characteristics, stimulates growth spurt at puberty, and stimulates spermatogenesis
parathyroid
the gland that increases blood calcium level, stimulates calcium reabsortion and activates vitamin D