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study of structure of an organism


mass of protoplasm; basic unit of structure of all animals and plants


area of cell cytoplasm that contains two centrioles; important in reproduction of cell


located in nucleus & made of deoxyribonucleic acid and protein.

connective tissue

body tissue that connects, supports or binds body organs


fluid inside a cell; contains water, proteins, lipids, carbohydrates, minerals, and salts


insufficient amounts of fluid in tissues


swelling; excell amount of fluid in tissues

endoplasmic recticulum

fine network of tubular structures in the cytoplasm of a cell; allows for the transport of materials in and out of the nucleus and aids in the synthesis and storage of protein.

epithelial tissue

tissue that forms the skin and parts of the secreting glands, and that lines the body cavities.


the structures on chromosomes that carry inherited characteristics.


is the total mass of genetic instruction humans inherit from their parents.

golgi apparatus

that structure in the cytoplasm of a cell that produces, stores, and packages secretions for discharge from the cell.


those structures in the cytoplasm of a cell that contain digestive enzymes to digest and destroy old cells, bacteria and foreign matter.


the process of cell division that occurs in gametes or sex cells (ovum and spermatozoa)


those structures in a cell that provide energy and are involved in the metabolism of the cell.


process of asexual reproduction by which cells divide into two identical cells

muscle tissue

body tissue composed of fibers that produce movement

nerve tissue

body tissue that conducts or transmits impulses throughout the body.


the spherical body in the nucleus of a cell that is important in reproduction of the cell.


the structure in a cell that controls cell activities such as growth, metabolism and reproduction


body part made of tissues that have joined together to perform a special function


structures in the cytoplasm of a cell including the nucleus, mitochondria, ribosomes, lysosomes and Golgi apparatus


study of how disease occurs and the responses of living organisms to disease processes.

pinocytic vessicles

pocketlike folds in the cell membrane that allow large molecules such as proteins and fats to enter the cell.


thick, viscous substance that is the physical basis of all living things


study of the processes or functions of living organisms

stem cells

have the ability to transform themselves into any of the body's specialized cells and perform many different functions.


group of organs and other parts that work together to perform a certain function


a group of similar cells that join together to perform a particular function.


pouchlike structures found throughout the cytoplasm that have a vacuolar membrane with the same structure as the cell membrane. they are filled with a watery substance, stored food or waste products.

abdominal cavity

is divided into an upper and lower part. The upper contains the stomach, small intestine, most of large intestine, appendix, liver, gallbladder, pancreas and spleen. the lower contains the urinary bladder, reproductive organs and last part of the large intestine.

abdominal regions

divisions of the abdominal cavity


means before or in front of

body cavities

spaces within the body that contain vital organs. (dorsal/posterior cavity and ventral/anterior cavity)

body planes

are imaginary lines drawn through the body at various parts to separate the body into sections

buccal cavity

for the teeth and tongue


body parts located near the sacral region of the spinal column (also known as the "tail")


means body parts located near the head

cranial cavity

contains the brain


body parts distant from the point of reference


body parts on the back of the body

dorsal cavity

one long, continuous cavity located on the back of the body, divided into 2 sections (cranial & spinal)

frontal (coronal) plane

divides the body into a front section and a back section.


body parts below other parts


body parts away from the midline


body parts close to the midline or plane

midsagittal (median) plane

divides the body into right and left sides

nasal cavity

for the nose structures

orbital cavity

for the eyes

pelvic cavity

(lower abdominal cavity) contains the urinary bladder, the reproductive organs and last part of large intestine


towards the back; behind


body parts close to the point of reference

spinal cavity

contains the spinal cord


body parts above other parts

thoracic cavity

is located in the chest and contains the esophagus, trachea, bronchi, lungs, heart and large blood vessels

transverse plane

is a horizontal plane that divides the body into a top half and a bottom half.


body parts in front of the plane or on the front of the body

ventral cavity

larger than the dorsal cavity. It is separated into 2 distinct cavities by the dome-shaped muscle called the diaphragm.


a person with an absence of color pigments


baldness, a permanent loss of hair on the scalp.


to contract or narrow; to make smaller


areas of dried pus and blood, commonly called scabs


a bluish discoloration of the skin, lips or nail beds caused by insufficient oxygen


also called corium or "true skin". has framework of elastic connective tissue and contains blood vessels, lymph vessels, nerves,involuntary muscle, sweat and oil glands and hair follicles.


enlarge or expand; to make bigger


the outermost layer of skin made up of 5 smaller layers by no blood vessels or nerve cells.


is a reddish color of the skin that can be caused by either burns or a congestion of blood in vessels

integumentary system

or skin, has been called both a membrane, because it covers the body, and an organ because it contains several kinds of tissues.


a yellow discoloration of the skin, can indicate bile in the blood as a result of liver or gallbladder disease; or occurs in conjunction with certain diseases that involve destruction of red blood cells


(macular rash) flat spots on the skin, such as freckles


a brownish black pigment produced in the epidermis by specialized cells called melanocytes


(papular rash) firm, raised areas such as pimples and the eruptions seen in some stages of chickenpox and syphilis


pus-filled sacs such as those seen in acne, or pimples

sebaceous glands

are oil glands that open onto hair follicles. They produce sebum, an oil that keeps the skin and hair from becoming dry and brittle.

subcutaneous fascia (hypodermis)

the innermost layer of skin. It is made of elastic and fibrous connective tissue and adipose (fatty) tissue and connects skin to underlying muscles.

sudoriferous glands

are sweat glands. They are coiled tubes that extend through the dermis and open on the surface of skin at pores.


a deep loss of skin surface that may extend into the dermis; may cause periodic bleeding and the formation of scars


blisters, or fluid-filled sacs, such as those seen in chickenpox


itchy, elevated areas with an irregular shape; hives and insect bites are examples

appendicular skeleton

forms the extremities and is composed of the shoulder girdle, arm bones, pelvic girdle, and leg bones

axial skeleton

forms the trunk of the body and is composed of the skull, spinal column, ribs and breastbone.


bones of the wrist




is the spherical structure that surrounds and protects the brain.


the long shaft or middle section of a long bone


is a membrane that lines the medullary canal and keeps the yellow marrow intact. It also produces some bone growth.


the end or head at the extremity of a long bone


thigh bone of the leg; the longest and strongest bone of the body


slender smaller bone of the lower leg that attaches to the proximal end of the tibia


spaces in the cranium that allow for the enlargement of the skull as brain growth occurs. they are made of membrane and cartilage and turn to solid bone at 18 months of age.


are openings in bones that allow nerves and blood vessels to enter or leave the bone.


long bone of the upper arm


are areas where two or more bones join together.


connective tissue bands which help hold long bones together at joints

medullary canal

is a cavity in the diaphysis filled with yellow marrow


palm of hand; bone on hand between wrist and each finger.


bone of foot between instep and toe

os coxae

hipbone which join with the sacrum on the dorsal part of the body.




a tough membrane covering out of bone. It contains blood vessels, lymph vessels and osteoblasts, special cells that form new bone tissue.


bones of the fingers and toes

red marrow

is found in certain bones, such as the vertebrae, ribs, sternum and cranium, and in the proximal ends of humerus and femur. it produces red blood cells (erythrocytes), platelets (thrombocytes) and some white blood cells (leukocytes)


or (costae). They attach to the thoracic vertebrae on the dorsal surface of the body.


shoulder blade or bones


are air spaces in the bones of the skull that act as resonating chambers for the voice. They are lined with mucous membranes.

skeletal system

is made of organs called bones. an adult human has 206 bones.


or breastbone, is the last bone of the axial skeleton


are areas where the cranial bones have joined together


one of seven bones that form the instep of the foot; ankle


the larger weight-bearing bone between the ankle and the knee commonly called the shin bone


larger long bone on forearm between wrist and elbow


The 26 bones of the spinal column

yellow marrow

is mainly a storage area for fat cells. It also contains cells that form leukocytes (white blood cells)


long bone on forearm between wrist and elbow


.moving a body part toward the midline

cardiac muscle

forms the walls of the heart and contracts to circulate blood


moving in a circle at a joint or moving one end of a body part in a circle while the other end remains stationary; such as swinging an arm in a circle


to become short; draw together


muscle fibers that are stimulated by nerves contract or become short and thick, which causes movement


a severe tightening of a flexor muscle resulting in bending of a joint.


allows muscle to return to its original shape after it has contracted or stretched


irritability, the ability to respond to a stimulus such as a nerve impulse


the ability to be stretched


increasing the angle between two bones, or straightening a body part


a tough, sheetlike membrane that covers and protects the tissue


decreasing the angle between two bones, or bending a body part


end or area of muscle that moves when muscle contracts


means function without conscious thought or control

muscle tone

the state of partial contraction providing a state of readiness to act

muscular system

system made up of more than 600 muscles


end or area of a muscle that remains stationary when muscle contracts


turning a body part around its own axis; such as turning head from side to side

skeletal muscle

attached to bones and causes body movement


are strong, tough, fibrous connective-tissue cords.

visceral (smooth) muscle

is found in the internal organs of the body, such as those of digestive and respiratory systems, and blood vessels and eyes


under one's control


moving a body part away from the midline


is a mass of nerve tissue well protected by membranes and the cranium, or skull

central nervous system (CNS)

consists of the brain and spinal cord


the section below the back of the cerebrum; responsible for muscle coordination, balance, posture and muscle tone.

cerebrospinal fluid

a clear, colorless fluid in the ventricles of brain. this fluid circulates continually between ventricles and through subarachnoid space. serves as shock absorber to protect brain and spinal cord; also carries nutrients to some parts of brain and spinal cord and helps remove metabolic waste.


the largest and highest section of brain; responsible for reasoning thought, memory, judgment, speech, sensation, sight, smell, hear and voluntary body movement.


the section located between the cerebrum and midbrain; containing two structures - the thalamus and hypothalamus


regulates and controls the autonomic nervous system, temperature, appetite, water balance, sleep and blood vessel constriction and dilation. It is also involved in emotions such as anger, fear, pleasure, pain and affection

medulla oblongata

the lowest part of the brainstem; connects with the spinal cord and is responsible for regulating heartbeat, respiration, swallowing, coughing and blood pressure


are three membranes that cover and protect the brain and spinal cord. Dura mater - thick, tough outer layer; arachnoid membrane - middle layer is delicate and weblike, loosely attached to other meninges to allow space for fluid flow between layers; pia mater - innermost layer, is closely attached to brain and spinal cord, contains blood vessels that nourish nerve tissue.


the section located below the cerebrum at the top of the brainstem; responsible for conducting impulses between brain parts and for certain eye and auditory reflexes


are a combination of many nerve fibers located outside the brain and spinal cord.

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