CellsCells - the basic unit of living organisms; weren’t discovered until the invention of the microscopemicroscope (Anton van Leewenhoek).

The Discovery of Cells

The term “cells” was a term coined by Robert Hooke as he studied the first cork cells.

In fact, it was Hooke who coined the

term "cells": the boxlike

cells of cork reminded him of the cells of a monastery.

The Discovery of Cells

Types of Microscopes:Light MicroscopeLight Microscope – uses a series of lenses to magnify objects (1500x)Electron MicroscopeElectron Microscope – uses a beam of electrons instead of light to magnify structures

The Discovery of Cells

VIDEO HereVIDEO Here

Cells IntroCells Intro

Cell Theory (Schleiden and Schwann contributed to these fundamental ideas)All organisms are composed of one or more cells.The cell is the basic unit of structure and organization of organisms.All cells come from preexisting cells.

The Discovery of Cells

The Discovery of Cells

beforenucleus

truenucleus

The Discovery of Cells

Two basic types of cellsProkaryotesProkaryotes - cells that do NOT have membrane bound organelles.

EukaryotesEukaryotes – cells that do contain membrane bound organelles like the nucleus, chloroplast, or mitochondria

What do cells really look like?

Cardiac cells

Red Blood Cells

Nerve cells

HIVMacrophage attacking a bacteria

Why are cells so Why are cells so small ?????small ?????

http://www.cellsalive.com/howbig.htm

The Plasma Membrane

Survival of a cell depends the cell’s ability to maintain the proper conditions (homeostasis) within itself.The plasma membraneplasma membrane is a flexible boundary between the cell and its environment. The plasma membrane is selectively selectively permeablepermeable, which means that only certain molecules can pass through.

http://www.bio.davidson.edu/people/macampbell/111/memb-swf/membranes.swf

http://www.stolaf.edu/people/giannini/flashanimat/lipids/membrane%20fluidity.swf

http://telstar.ote.cmu.edu/biology/downloads/membranes/index.html

Hydrophilic head

Hydrophobic tails

VIDEO HereVIDEO Here

The Cell MembraneThe Cell Membrane

http://www.stolaf.edu/people/giannini/flashanimat/lipids/membrane%20fluidity.swf

Cool animationCool animation

http://telstar.ote.cmu.edu/biology/downloads/membranes/index.html

Parts of the CellParts of the CellRibosomes – site of protein synthesis, made up of rRNAGolgi apparatus – folded membranes that store and transports enzymes and hormones, also produces the cell wall in plantsCytoplasm – jelly-like material surrounding the nucleus of the cellNucleus – The control center of the cellNucleolus – Site of ribosome synthesisNuclear Membrane – Surrounds the nucleus. Cell Membrane – Membrane surrounding the organelles and the cytoplasm of the cell.

http://www.cellsalive.com/cells/cell_model.htm

Parts of the CellParts of the CellMitochondria – The site of cellular respiration or energy production. Membrane bound.Rough Endoplasmic Reticulum – forms a link between the nuclear membrane and the cell. Ribosomes are attached to the surface. Proteins are synthesized in the ribosomes and enclosed in vessicles and sent to the Golgi.Vacuole – Site of storage of glucose, water, salts, and toxic substances. Larger in plants cells than in animal cells.

Parts of the CellParts of the CellCell Wall – Plant, fungal, and bacteria have a cell wall that us used for support and protection. It is composed of cellulose.Chloroplast – Site of photosynthesis in the plant and algal cell. They are generally lens shaped and bound by a double membrane.Smooth Endoplasmic Reticulum – It forms a link between the nuclear membrane and the cell. Site of many metabolic reactions and synthesis of phospholipids and fatty acids.

Parts of the CellParts of the CellLysosome – Contain enzymes needed for digesting food, viruses, bacteria and old cells.Centrioles – Not normally found in plant cells. They are found in animal cells in pairs and are necessary for cell division.