2 - Chapter 2 - Cells to Organ Systems (Key Terms)

adenosine triphosphate (ATP)

The energy compound of the cell that stores energy needed for cell activities

carbohydrates

The category of organic compounds that includes sugars and starches

cell

The basic structural and functional unit of the living organism, a microscopic unit that combines with other cells to form tissues (root: cyt/o)

chromosome

A thread-like body in a cell’s nucleus that contains genetic information

cytology

Study of cells

cytoplasm

The fluid that fills a cell and holds the organelles

deoxyribonucleic acid (DNA)

The genetic compound of the cell, makes up the genes

enzyme

An organic substance that speeds the rate of a metabolic reaction

gene

A hereditary unit composed of DNA and combined with other genes to form the chromosomes

glucose

A simple sugar that circulates in the blood, the main energy source for metabolism (roots: gluc/o, glyc/o)

histology

Study of tissues

homeostasis

A steady state, a condition of internal stability and constancy

lipid

A category of organic compounds that includes fats (root: lip/o)

membrane

A simple, very thin, and pliable sheet of tissue that might cover an organ, line a cavity, or separate structures

metabolism

The sum of all the physical and chemical reactions that occur within an organism

mitosis

cell divison

mucus

A thick fluid secreted by cells in membranes and glands that lubricates and protects tissues (roots: muc/o, myx/o); the adjective is mucous

nucleus

The cell’s control center; directs all cellular activities based on the information contained in its chromosomes (roots: nucle/o, kary/o)

organ

A part of the body with a specific function, a component of a body system

organelle

A specialized structure in the cytoplasm of a cell

protein

A category of organic compounds that includes structural materials, enzymes, and some hormones

ribonucleic acid (RNA)

An organic compound involved in the manufacture of proteins within cells

tissue

A group of cells that acts together for a specific purpose (roots: hist/o, histi/o); types include epithelial tissue, connective tissue, muscle tissue, and nervous tissue