INTRO TO CELLS

Facts

Cells are the fundamental units of life. All living organisms are composed of

and depend on cells to function normally.

Scientists estimate that our bodies contain anywhere from 75 to 100 trillion cells.

Cells do everything from providing structure and stability to providing energy and a means of reproduction for an organism.

There are more bacterial cells in the body than human cells.

Scientists have estimated that about 95% of all the cells in the body are bacteria

Cells contain genetic material. Cells contain DNA

There are many types of cells.

Different types of cells reproduce through different methods.

Most prokaryotic cells reproduce by a process called binary fission (cloning process)

Eukaryotic organisms go through mitosis.

Groups of similar cells form tissues.

Cells have varying life spans. Cells have different life

spans based on the type and function of the cell.

Certain cells of the digestive tract live for only a few days, while some immune system cells can live for six weeks.

Pancreatic cells can live for as long as a year.

Cells commit suicide.

When a cell becomes damaged or undergoes some type of infection, it will self destruct by a process called apoptosis.

Apoptosis keeps the body’s natural process of cell reproduction in check.

A cell’s inability to undergo apoptosis can result in the development of cancer.

Two Main Types of Cells

Prokaryotic Lack a membrane

bound nucleus DNA is not found in

the nucleus Shapes: rod,

spherical, spiral Bacteria

Eukaryotic Membrane bound nucleus Many organelles that perform functions Kingdoms: Animalia, Plantae, Fungi,

Protista

Plant and Animal Cells

Animal Plant

Have a cell membrane

Nucleus Other organelles

Cell membrane and nucleus

Have a rigid cell wall to hold its shape

Chloroplasts for photosynthesis