Transcript Cells are - Bibb County Schools

Cell Structure
& Function
http://koning.ecsu.ctstateu.edu/cell/cell.html
History
of
Cell
Discovery
Cells are
the basic unit of structure
and function in living things
Robert Hooke
1635 – 1703
Hooke was one of the first people
to observe cells
He published a book,
Micrographia, in 1665.
It had ideas about:
the life cycle of mosquitoes
origin of craters on the moon
fossils and drawings of
microscopic things.
Thin slices
of cork from
the cork tree.
(tiny rooms –
cells)
He was really
looking at
dead cells –
what was left
was the cell
wall.
Anton van Leeuwenhoek
(1632-1723)
Anton van Leeuwenhoek’s
simple microscope
He looked at:
drops of lake water
scrapings from gums and teeth
water in rain gutters
He saw tiny moving organisms
and called the wretched
beasties “animalcules.”
Bacteria from the mouth
200 years later…
Matthias Schleiden (1804-1881)
German botanist
1838
he suggested that
all plants are
made of cells
Theodor Schwann (1810-1882)
German zoologist
1839
suggested that
animals, not just
plants are made of
cells
Rudolf Virchow (1821-1902)
German doctor
1855
“all cells come
from cells”
The work of
these last three
men led to…
The
Cell
Theory
Robert Hooke 1665
• First to see “cells”
under a microscope
that he created.
Anton Van Leewenhoek 1674
• One of the first
scientist to observe
living things in pond
water with a single
lens microscope
Robert Brown- 1831
• Discovered the cell
nucleus
Matthias Schleiden - 1838
• First to discover that
plants are made up of
cells
Theodor Schwann
• Discovered that all
animals are made up
of cells
Rudolph Virchow
• Virchow's many
discoveries include
cells in bone and
connective tissue
• In 1855 he published
his now-famous
aphorism omnis
cellula e cellula
("every cell stems
from another cell").
The Cell Theory
• All living things are made up of one or
more cells.
• Cells are the basic units of structure and
function in living things.
• New cells are produced from existing cells.
The cell theory states:
All living things
are
made of one or
more cells
The cell theory states:
Cells are the
basic unit of
structure and
function in
living things
The cell theory states:
Living cells
only come from
other living
cells
The Cell Theory
The modern tenets of the Cell Theory include:
1. All known living things are made up of cells.
2. The cell is structural & functional unit of all living
things.
3. All cells come from pre-existing cells by division.
(Spontaneous Generation does not occur).
4. Cells contains hereditary information which is
passed from cell to cell during cell division.
5. All cells are basically the same in chemical
composition.
6. All energy flow (metabolism & biochemistry) of life
occurs within cells.
Cell Theory
• All living things are made up of one or
more cells.
• Cells are the basic unit of structure and
function -smallest working units of all living
things.
• All cells come from preexisting cells
through cell division.
Definition of Cell
A cell is the smallest unit that is
capable of performing life
functions.
Two Types of Cells
•Prokaryotic
•Eukaryotic
Prokaryotic
• Do not have
structures
surrounded by
membranes
• Few internal
structures
• One-celled
organisms,
Bacteria
http://library.thinkquest.org/C004535/prokaryotic_cells.html
Prokaryotic Cells
• “Simple” Cells
• Do not contain a
nucleus.
• Does contain a cell
membrane and
cytoplasm.
• Example: Bacterial
cell
Eukaryotic Cells
• “Complex” Cell
• Contains a nucleus
and several
membrane bound
organelles in addition
to cytoplasm and a
cell membrane.
Eukaryotic
• Contain organelles surrounded by membranes
• Most living organisms
Plant
http://library.thinkquest.org/C004535/eukaryotic_cells.html
Animal
Examples of Cells
Amoeba Proteus
Plant Stem
Bacteria
Red Blood Cell
Nerve Cell
“Typical” Animal Cell
http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif
“Typical” Plant Cell
http://waynesword.palomar.edu/images/plant3.gif
Plant vs. Animal Cells
Cell Parts
Organelles
Surrounding the Cell
Cell Membrane
• Outer membrane of cell
that controls movement
in and out of the cell
• Double layer
http://library.thinkquest.org/12413/structures.html
Cell Wall
• Most commonly found
in plant cells &
bacteria
• Supports & protects
cells
http://library.thinkquest.org/12413/structures.html
Inside the Cell
Nucleus
• Directs cell activities
• Separated from cytoplasm by nuclear
membrane
• Contains genetic material - DNA
Nuclear Membrane
• Surrounds nucleus
• Made of two layers
• Openings allow
material to enter and
leave nucleus
http://library.thinkquest.org/12413/structures.html
Chromosomes
• In nucleus
• Made of DNA
• Contain instructions
for traits &
characteristics
http://library.thinkquest.org/12413/structures.html
Nucleolus
• Inside nucleus
• Contains RNA to build
proteins
http://library.thinkquest.org/12413/structures.html
Cytoplasm
• Gel-like mixture
• Surrounded by cell membrane
• Contains hereditary material
Endoplasmic Reticulum
• Moves materials around
in cell
• Smooth type: lacks
ribosomes
• Rough type (pictured):
ribosomes embedded in
surface
http://library.thinkquest.org/12413/structures.html
Ribosomes
• Each cell contains
thousands
• Make proteins
• Found on ribosomes
& floating throughout
the cell
http://library.thinkquest.org/12413/structures.html
Mitochondria
• Produces energy through
chemical reactions –
breaking down fats &
carbohydrates
• Controls level of water and
other materials in cell
• Recycles and decomposes
proteins, fats, and
carbohydrates
http://library.thinkquest.org/12413/structures.html
Golgi Bodies
• Protein 'packaging
plant'
• Move materials within
the cell
• Move materials out of
the cell
http://library.thinkquest.org/12413/structures.html
Lysosome
• Digestive 'plant' for
proteins, fats, and
carbohydrates
• Transports undigested
material to cell
membrane for removal
• Cell breaks down if
lysosome explodes
http://library.thinkquest.org/12413/structures.html
Vacuoles
• Membrane-bound
sacs for storage,
digestion, and waste
removal
• Contains water
solution
• Help plants maintain
shape
http://library.thinkquest.org/12413/structures.html
Chloroplast
• Usually found in plant
cells
• Contains green
chlorophyll
• Where
photosynthesis takes
place
http://library.thinkquest.org/12413/structures.html
Cell Organelles
• http://www.execulink.com/~ekimmel/drag_
gr11/organell.htm
• http://www.tvdsb.on.ca/westmin/science/S
bi3a1/cells/cellquiz.htm
• http://www.biologycorner.com/bio1/cellquiz
.html