Download Cells - Fort Thomas Independent Schools

Cells
The basic unit of life
© susan anderson 2008-2010
Discovery of Cells

1590 – Invention of the microscope
allowed people to see cells for the first
time.
 Hand
lens is simple microscope.
 A compound microscope has more than one
lens.
Early Cell Scientists

Robert Hooke
– one of the first to see cells
 Saw cork cells
 Named them “cells”
 1663

Van Leeuwenhoek
 Mid
1600’s
 Viewed pond water
 Saw small organisms (he called animalcules)
Early Cell Scientists

Schleiden, Schwann, and Virchow
 1838
– botanist
 Schwann – zoologist
 Virchow – doctor (1855)
 Together developed “The Cell Theory”
 Schleiden
“The Cell Theory”
All living things are made of cells.
 Cells are the basic unit of structure and
function in living things.
 Cells all come from other cells.


**This theory holds true for all living things
Looking inside cells - Organelles

Cell Wall – rigid outer layer of plant and
some other cells.

Cell Membrane – selectively permeable
boundary
Looking inside cells - Organelles

Nucleus – control center
 Nuclear
membrane protects
nucleus/boundary.
 Chromatin are the strands of genetic material.
 Nucleolus is where ribosomes are made.
Looking inside cells - Organelles
Cytoplasm – between the cell membrane
and the nucleus; gel-like fluid.
 Mitochondria – produces most of the
energy for the cell.
 Endoplasmic Reticulum –passageways
around the cell.

Looking inside cells - Organelles
Ribosomes – builders of proteins
 Golgi Bodies – package and
distribute chemicals in the cell.
 Chloroplasts – found in plant cells, capture
energy from the sun and use it to make
food.

Looking inside cells - Organelles
Vacuoles – store food and other materials
 Lysosomes – break down old materials
and release materials to be recycled.

Bacterial Cells
Does not have a nucleus (prokaryote)
 Genetic material found in cytoplasm
 Only organelles are ribosomes

 Cells
that have a nucleus, like plants and
animals are called eukaryotes.
Cell Specialization

Cells’ structure reflect their function
 Blood
cells
 Skin cells
 Nerve cells