cells

DNA

DNA is the genetic material that carries information needed to make new cells and new organisms. The DNA is inside the nucleus and is passed from parent cells to new cells.

nucleus

In a eukaryotic cell, nucleus is a membrane-bound organelle that contains the cell's DNA and has a role in the processes such as growth, metabolism, and reproduction.

cells

In biology, cell is the smallest unit that can perform all life processes. Cells are covered by a cell membrane, have cytoplasm and DNA.

organelle

One of the small bodies in the a cell's cytoplasm that are specialized to perform a specific function.

ATP

When the mitochondrion makes energy, it stores it in ATP and then the cell uses ATP to do work.

endoplasmic reticulum (ER)

ER is a system of folded membranes that is found in the cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids. ER is also considered the highway of the cell because it carries proteins and other materials from one part of the cell to another.

mitochondrion (plural: Mitochondria)

In Eukaryotic cells, the Mitochondrion is the cell organelle that is surrounded by two membranes and is the site of cellular respiration. Mitochondrion breaks down sugar and produces energy. The energy is stored in ATP and the cell uses ATP to do work. Mitochondria are the powerhouse of the cell and produce energy for the cell.

cytoplasm

The gel-like fluid inside the cell where organelles float.

ribosome

A cell organelle composed of RNA and protein; Ribosomes are the site of protein synthesis, which means they are factories the make proteins. All cells have ribosomes. Ribosomes are the smallest of all organelles and maybe attached to the ER or float in cytoplasm.

lysosome

A cell organelle that contains digestive enzymes. Lysosomes digest food particles, wastes, cell parts, and foreign invaders. Lysosomes are the cell's clean-up crew. They digest worn-out or damaged organelles, get rid of waste and protect cells from foreign invaders like bad bacteria. Lysosomes are mainly found in animal cells.

Golgi complex

A cell organelle that helps make and package materials to be transported out of the cell. Lipids and proteins from ER are delivered to the Golgi complex. Golgi Complex is like the mail room or post office of the cell. It receives materials, packages them and then distributes them.

chloroplasts

A cell organelle that uses/absorbs the energy of sunlight to make food. It is green because is contains chlorophyll. Chloroplasts are the site of photosynthesis.

cell membrane

A phospholipid layer that covers the cell's surface; it acts as a protective barrier between the inside of a cell and the cell's outside environment. Cell membrane controls materials going into and out of the cell. Cell membranes contains proteins, lipids (fats and cholesterol) and phospholipids.

cell wall

A rigid or stiff structure that surrounds the cell membrane and provides support to the cell so that they can keep their shape. Plant cells have cell walls. Animal cells do not have cell walls.

vesicle

A small cavity or sac that contains materials in a eukaryotic cell that need to be moved into or out of the cell. Vesicles move materials within a cell or in and out of a cell. For example, vesicles carry protein from the ER to Golgi Complex and from Golgi Complex to other parts of the cell.

What do all cells have?

All cells have cell membranes, organelles, cytoplasm and DNA.

proteins

All cells need proteins to live, therefore all cells have ribosomes. Ribosomes make proteins for the cell.

eukaryote

An organism made up of cells that have a nucleus enclosed by a membrane; eukaryotes include animals, plants, humans, and fungi, but not bacteria and archaea.

prokaryote

An organism that consists of a single cell that does not have a nucleus or membrane-bound organelles. Examples are bacteria and archaea.

What controls the size of a cell?

Cell's surface area-to-volume ratio. Cell's cannot get very large because of the cell's surface area-to-volume ratio. Volume of a cell increases faster than its surface area and because of this cells would not be able to get enough food and get rid of the waste fast enough and so they will die.

cytoskeleton

Cytoskeleton is a web of proteins in the cytoplasm. Cytoskeleton acts both like a muscle and a skeleton. It helps cell's membranes from collapsing and also helps some cells move.

vacuole

a vesicle; in plant cells some vacuoles act like lysosomes and store digestive enzymes; the large central vacuole in plant cells stores water and other liquids