A phospholipid layer that covers a cell's surface and acts as a barrier between the inside of a cell and the cell's environment.
An organelle found in the plant and algae cells where photosynthesis occurs.
A collection of genetically identical cells that are permanently associated but in which little or no integration of cell activities occurs.
The region of the cell within the membrane.
A system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and the production of lipids.
A single-celled organism that has a nucleus and membrane-bound organelles.
A cell organelle that helps make and package materials to be transported out of the cell.
In eukaryotic cells, the cell organelle that is surrounded by two membranes and that is the site of cellular respiration.
In a eukaryote cell, a membrane-bound organelle that contains the cell's DNA.
A collection of tissues that carry out a specialized function of the body.
A group of organs that work together to perform body functions.
One of the small bodies that are found in the cytoplasm of a cell and that are specialized to perform a specific function.
An organism that does not have nucleus or membrane-bound organelles - sometimes surrounded by a sticky capsule.
A cell organelle where protein synthesis occurs.
A group of similar cells that performs a common function.
A fluid-filled vesicle found in the cytoplasm of plant cells or protists.
A small cavity or sac that contains materials in a eukaryotic cell.
In 1665 this English scientist viewed a slice of cork through a crude microscope and discovered "cells."
Anton van Leeuwenhoek
In 1675 this Dutch scientist discovered single-celled organisms while viewing pond water through this microscopes.
States that all living things are composed of cells, that cells are the basic units of structure and function in organisms, and that all cells arise from existing cells (Schleiden, Schwan, and Virchow).
A cell's shape reflects the cell's function.
Cell size is limited by a cell's surface area-to-volume ratio.
The fluid inside the cell that is full of dissolved particles.
A web of protein fibers found in eukaryotic cells that supports the cell structure.
A type of cytoskeleton - these are long, thin fibers attached to the cell membrane and can expand or contract the cell membrane.
A type of cytoskeleton - they are thick, hollow fibers and information molecules move through them to various parts of the cells.
A type of cytoskeleton - moderately thick and mainly anchor organelles and enzymes to certain parts of the cell.
This is a double membrane that surrounds the nucleus - it has many nuclear pores that allow certain molecules to move in and out of the nucleus.
The prominent structure within the nucleus - is also the region where ribosome parts are made.
Endoplasmic Reticulum with ribosomes attached to its surface. Proteins formed enter the ER and are packaged in vesicles.
Endoplasmic Reticulum with no attached ribosomes - makes lipids and breaks down toxic substances.
A vesicle that contains specific enzymes that breaks down large molecules.
Used to pump excess water out of the cell of protists.
A long, hairlike structure that grown out of a cell and enables the cell to move.
Short, thick outgrowths on some prokaryotes that allow them to attach to surfaces or to other cells.
Composed of many individual, permanently associated cells that coordinate their activities.
The process by which cells develop specialized forms and functions.