Cells & Microscope

What is a cell?

It is what all living things are made of.

DEFINITION

A cell is the basic unit of any organism or living thing. This means that it is the smallest “part” that is able to carry out life processes.

THE DISCOVERY OF CELLS: In 1590, the microscope was invented by Zacharias Janssen At almost the same time, Galileo invented the telescope! By 1650, Anton van Leeuwenhoek and other scientists were using simple microscopes to examine many different materials. In 1655, Robert Hooke observed dead cork cells using a very basic microscope.

Van Leeuwenhoek discovered protozoa in 1674 and bacteria in 1683. From discoveries like these came the formation of the cell theory.

THE DEVELOPMENT OF THE CELL THEORY:

Cell Theory The Cell Theory When Schleiden and Schwann proposed the cell theory in 1838, cell biology research was forever changed. The cell theory and three parts and states that: All life forms are made from one or more cells. Cells only arise from pre-existing cells. The cell is the smallest form of life.

Types of Microscopes

Eyepiece Body Tube Coarse Adjustment Knob Arm Fine Adjustment Knob

Base

Nosepiece Objective Lenses Stage Clips Stage Diaphragm Illuminator

THE COMMON HOUSE FLY

Viewing cells and organisms • Dry Mount • Wet Mount http://www.pbrc.hawaii.edu/bemf/microangela/

Life Processes Life processes are characteristics of living things. These are activities or processes carried out by the cells of all living things. Whether an organism is only one cell or made up of many cells, all living things: produce organisms of the same kind, obtain energy from the environment (the chemical activities involved in this are called metabolism and include processes such as respiration and excretion), move, grow and develop at some point during their life spans,

How Big Are Cells?

So what about viruses?

amoeba

Cell Shapes

Green algae

White blood cell

Red blood cell Nerve cell

Cell Function In multicellular organisms, each kind of cell does its own special job. This is known as specialization.

Classification of Organisms based on type of cells

Green algae

Rod-shaped bacteria Fungus cell

Plant cells from a leaf

5 Kingdoms of Organisms with cells that differ in their characteristics:Protists; Fungi; Monera; Plants; Animals

Mouse cells

QUESTION: How does a cell, especially an organism that is only made up of a single cell, carry out all of the activities and the life processes and survive ?

Parts of Cells

ANSWER: The cells have even smaller parts called organelles (tiny organs).

 nucleus

 cytoplasm

 Golgi  mitochondria body  cell wall  vacuoles

 lysosomes

 endoplasmic reticulum

 cell membrane

 ribosomes

Bibliography

http://www.neosoft.com/~uthman/blood_cells.html http://library.thinkquest.org/3564/ http://megasun.bch.umontreal.ca/protists/protists.html

http://www.plantbio.ohiou.edu/pbc/plasmos/home.htm#contents http://www.pbrc.hawaii.edu/bemf/microangela/ http://www.biology.arizona.edu/cell_bio/tutorials/cells/cells2.html http://www.cellsalive.com/ http://www.biology.arizona.edu/cell_bio/tutorials/cells/cells3.html http://www.ucmp.berkeley.edu/history/hooke.html