Cell
Pronounced: sel
basic unit of all living things. The human body is composed of trillions of cells, which vary in size and shape according to function.
cell membrane
Pronounced: sel MEM-brān
forms the boundary of the cell
cytoplasm
Pronounced: SĪ-tō-plas-em
gel-like fluid inside the cell
nucleus
Pronounced: NŪ-klē-us
largest structure within the cell, usually spherical and centrally located. It contains chromosomes for cellular reproduction and is the control center and source of energy production for the cell.
chromosomes
Pronounced: KRŌ-ma-sōms
located in the nucleus of the cell. There are 46 chromosomes in all normal human cells, with the exception of mature sex cells, which have 23.
genes
Pronounced: JĒNS
regions within the chromosome. Each chromosome has several thousand genes that determine hereditary characteristics.
DNA
Pronounced: D-N-A
comprises each gene; is a genetic material that regulates the activities of the cell. DNA abbreviates deoxyribonucleic acid.
tissue
Pronounced: TISH-ū
group of similar cells that performs a specific function
muscle tissue
Pronounced: MUS-el TISH-ū
composed of cells that have a special ability to contract, usually producing movement
nervous tissue
Pronounced: NURV-us TISH-ū
similarly specialized cells united in the performance of a particular function; found in the nerves, spinal cord, and brain. It is responsible for coordinating and controlling body activities.
connective tissue
Pronounced: ke-NEK-tiv TISH-ū
connects, supports, penetrates, and encases various body structures. Adipose (fat), osseous (bone) tissues, and blood are types of connective tissue. Fibrous tissue is a type of connective tissue that provides strength and stability such as ligaments and tendons.
epithelial tissue
Pronounced: ep-i-THĒ-lē-al TISH-ū
the major covering of the external surface of the body; forms membranes that line body cavities and organs and is the major tissue in glands. Glandular tissue is designed to secrete substances such as digestive enzymes.
organ
Pronounced: OR-gen
two or more types of tissues that together perform special body functions. For example, the skin is an organ composed of epithelial, connective, muscle, and nervous tissue.
viscera
Pronounced: VIS-er-a
large internal organs contained in the body cavities, especially in the abdominal cavity
system
Pronounced: SIS-tem
group of organs that work together to perform complex body functions. For example, the cardiovascular system consists of the heart, blood vessels, and blood. Its function is to transport nutrients and oxygen to the cells and remove carbon dioxide and other waste products.
cranial cavity
Pronounced: KRĀ-nē-al KAV-i-tē
space inside the skull (cranium) containing the brain
spinal cavity
Pronounced: SPĪ-nal KAV-i-tē
space inside the spinal column containing the spinal cord
thoracic cavity
Pronounced: thō-RAS-ic KAV-i-tē
space containing the heart, aorta, lungs, esophagus, trachea, bronchi, and mediastinal area
abdominal cavity
Pronounced: ab-DOM-i-nal KAV-i-tē
space containing the stomach, intestines, kidneys, adrenal glands, liver, gallbladder, pancreas, spleen, and ureters
pelvic cavity
Pronounced: PEL-vik KAV-i-tē
space containing the urinary bladder, certain reproductive organs, parts of the small and large intestine, and the anus
abdominolpelvic cavity
Pronounced: ab-dom-i-nō-PEL-vik KAV-i-tē
both the pelvic and abdominal cavities
Basic unit of all living things
Cell
Pronounced: sel
The human body is composed of trillions of cells, which vary in size and shape according tofunction.
Forms the boundary of the cell
Cell membrane
Pronounced: sel MEM-brān
Gel-like fluid inside the cell
Cytoplasm
Pronounced: SĪ-tō-plas-em