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Overview of Body Systems


study of body structure


study of the body and its functions


A group of cells that work together for a common function


A group of tissues that work together for a common function

Organ System

group of organs that work together to perform a specific function

Integumentary System

covers and protects the body from infection, heat and moisture loss

Skeletal System

provides support and protection for the body and its organs

Digestive System

Ingest food and breaks it down into smaller unites to be used by the body

Circulatory System

The human body system that contains the heart, blood, and all of the blood vessels. It delivers all the nutrients to the cells and removes wastes

Respiratory System

system responsible for taking in oxygen and releasing carbon dioxide using the lungs

Nervous System

Coordinates body's activities by detecting stimuli and directing the body's responses

Muscular System

Enables body movement

Endocrine System

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream.

Excretory System

the system that removes waste from your body and controls water balance

Lymphatic System

a secondary circulatory system that helps the body fight pathogens and maintain its fluid balance

Immune System

Defends the body against infections

Reproductive System

system of organs involved in producing offspring

Epithelial Tissue

a body tissue that covers the surfaces of the body, inside and out

Connective Tissue

Groups of cells that support the body and hold it together

Nervous Tissue

tissue that receives messages from the body's external and internal environment, analyzes the data, and directs the response


a cell that is specialized to conduct nerve impulses

skeletal muscle

Voluntary, striated muscle that moves bones, works in pairs and is attached to bones by tendons

Cardiac Muscle

Striated, involuntary muscle found only in the heart

Smooth Muscle

involuntary, non-striated muscle found mainly in organs


process by which organisms maintain a relatively stable internal environment


a chemical that serves as a messenger. Each hormone is secreted by a gland and travels to one or more target organs, where it brings about responses.

interstitial fluid

fluid in the spaces between cells


the outer layer of the skin covering the exterior body surface of vertebrates


a pigment that gives the skin its color


the deep vascular inner layer of the skin


Subcutaneous tissue layer below the dermis


hard protein material found in the epidermis, hair, and nails


individual segment of the backbone; encloses and protects the spinal cord


a connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together

red marrow

produces blood cells

yellow marrow

bone marrow that is yellow with fat


strong connective tissue that holds bones together in movable joints


strong connective tissue that attaches muscle to bone

muscle fiber

an elongated contractile cell that forms the muscles of the body


one of many contractile filaments that make up a striated muscle fiber


contractile unit of muscle


protein that mainly makes up the thin filaments in striations in skeletal muscle cells


protein that makes up the thick filaments in striations in skeletal muscle cells

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