Cell Structure and Function

Cell

basic unit of all living things

Cell membrane

thin, flexible barrier around a cell; regulates what enters and leaves the cell

Cytoplasm

a jellylike fluid inside the cell in which the organelles are suspended

Cell wall

strong wall outside a plant cell's cell membrane that protects the cell and maintains its shape

Organelle

a tiny cell structure that carries out a specific function within the cell

Nucleus

organelle that controls all the activities of a cell and contains hereditary material made of proteins and DNA

Chloroplast

a structure in the cells of plants and some other organisms that captures energy from sunlight and uses it to produce food

Mitochondrion

bean shaped organelle that releases energy from stored food molecules which supplies energy for the cell

Ribosome

an organelle that is resposible for making proteins.

Endoplasmic reticulum

a cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another.

Golgi body

A structure in a cell that receives proteins and other newly formed materials from the endoplasmic reticulum, packages them, and distributes them to other parts of the cell.

Tissue

group of similar cells that perform a particular function

Organ

a collection of tissues that carry out a specialized function of the body

Organ system

group of organs that work together to perform a specific function

Organism

Any living thing

Mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes

Meiosis

A process in cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus, which results in the production of sex cells

Chromosome

a structure in the nucleus that contains hereditary material

Vacuole

an organelle that stores food, water, and other materials needed by the cell

Multicellular

organisms composed of many cells

Unicellular

a type of organism that is made up of a single cell

cytoskeleton

reinforces cell shape, functions in movement

components are made of protein

microtubules

forms mitotic spindle and maintains cell shape

microfilaments

fibrous proteins; forms cellular cortex

intermediate filaments

provide structural support and tensile strength, anchoring organelles in place.

centrosome

microtubule organizing center

peroxisome

an organelle involved in the breakdown of fatty acids and detoxification of hydrogen peroxide

metabolizes waste

nuclear envelope

a double membrane that surrounds the nucleus, protecting its contents. protein-lined pores allow material to move in and out

nucleolus

structure where ribosomes are formed