Download The Cell - Belle Vernon Area School District

The Cell
Basic Unit of Life
The Cell
I. Introduction to the cell
The concept that all living material is made of cells or
chemical products of cells is a CENTRAL, unifying theme
in modern biology.
II. Cell has all the characteristics of Life
A. Grow
D. Respond to stimuli
B. Reproduce
E. Homeostasis
C. Move
F. Organized
III. The cell is the fundamental unit of life
Cell Time Line of Discovery
A. Discovery of the cell
1. 1665 Robert Hooke examine cork and noticed
that the material was made
up of “little boxes” or cells.
(DEAD material only).
2. 1675 Anton van
Leeuwenhoek microscopic
creatures.
Bacteria & protista.
(Living material).
Leeuwenhoek
3. 1805 Lorenz
Oken - first
initial
statement of
the cell theory.
4. 1838 Mathias
Schleiden - conclude
that plants were
composed of cells.
5. 1839 Theodore
Schwann - concluded
that animals were
composed of cells.
6. 1855 Rudolph
Virchow - while
studying
disease,
determined that
cells only come
from other cells.
Cell Theory
1. All living material is made up of cells or the products of
cells.
2. Cells come from preexisting cells.
3. The cell is the most elementary form of life.
4. Every cell has a cell membrane that separates it from the
environment & from other cells.
5. Most cells are small 0.001 cm.
Cell Diversity
All living things are made of cells, but not all cells are identical.
A. Size & Shape
2m long, nerve cells down a giraffe’s neck to 0.2 um.
 Most are around 10 - 50 um.
 Many are cuboidal (plants) or spherical (animals).
 Cells then are limited in size by the ratio of volume to
surface area.
B Two Types of cells
1. Prokaryote - No nucleus
ex. Bacteria
2. Eukaryote – Nucleus
ex. Protista, Fungi, Plants, Animals
Plant vs Animal Cells
1. Plant
a. Square
b. Large water vacuole
c. Chloroplasts
2. Animal cells
a. Circle
b. Centrioles
Multicellular Organization
 Organization from very simple to very
complex
 Division of labor occur within a cell.
 Certain organelles carry out specific
functions.
 Each cell depends on all other cells to
perform one or more of the life
functions.
Inner Life of a Cell
Tissues, Organs, & Organ
Systems
1.
Molecule-group of atom held together by bonds. (water,
phosphate).
2.
Organelle-cell component that preforms a specific function.
(Mitochondria SER, RER, Nucleus).
3.
Cell-basic unit of life (Nerve Cell).
4.
Tissue-group of similar cells that carry out a common
function. (Nervous Tissue).
5.
Organ-several type of tissues that together perform a bodily
function. (Brain).
6.
Organ System -a groups of organs that work together that
perform a related task. (Brain, spinal cord, nerves).
7.
Organism-a living thing. (Human).