Download Cells and Cell Theory

Cells and Cell
Theory
Organisms – living things

All organisms are made up of cells.
 Multicellular:
 Examples:
 Unicellular:
 Examples:
made of many cells
Insects, snails, fish, people
made of one cell
bacteria, protists
Exception: Viruses
-
Not alive
-
Made of proteins, not cells
Organ system  organ 
tissues  cells  organelles
 Organ
- Group of different tissues
that work together to do a certain
job
 Organ
 Tissue
system – a group of organs
- Group of cells that look
alike and work together to do a
certain job
Cell Theory (a scientific
theory, not a law!)

All living things or organisms are
made of cells

New cells are created by old cells
dividing into two cells

Cells are the basic building units of
life
Cells

Basic unit of life

The smallest living things

First observed by Robert Hooke
(1665-1703)
A
cell is like a factory with each
“worker” having its own job.
 There
are many types of cells,
doing many different jobs in
plants and animals.
Types of Cells

Eukaryotic
 Single
 Has
cell
a nucleus
 All
organisms EXCEPT bacteria and
archaea

Prokaryotic
 Simplest
 No
type of cell
nucleus
 DNA
and other materials float freely
within the cytoplasm
 Bacteria
and archaea
Other Vocab

Diffusion – Material moves from crowded area
to less crowded area
 Homeostasis
- Ability of organisms
to maintain a state of balance

Example: We maintain our body temperature by
shivering to get warm and sweating to cool off.
Organelle - Small structure inside a cell that
performs a certain job

Endoplasmic Reticulum (ER) - system of tubes
that move proteins within a cell

Golgi Bodies - package and distribute (move)
proteins outside the cell
•
Lysosome: digests waste, breaks down
substances
•
Mitochondria: use oxygen to release energy,
power supply

Ribosome - Small round structure that makes
proteins
 Meiosis
 Process
of cell division
 Results
in reproductive cells
 Mitosis
 Process
of cell division
 Results
in two cells
 Cells
are identical to the parent cells
Animal vs. Plant
Cells
Three Main Parts of Cells
Cell Membrane
2. Nucleus
3. Cytoplasm
1.
Cell Membrane

Thin layer

Encloses (surrounds) the cell

Controls movement of materials
into and out of the cell

Provides shape to the cell

Provides protection for the cell
Nucleus

Controls all cell activity

Round or egg-shaped

Found near the center of the cell

Dark in color

Contains DNA
 Deoxyribonucleic
Acid: chemical in
chromosomes that stores information
about the organism
Cytoplasm

Gel-like

Contains all the living material except the
nucleus
 Examples:
 Proteins
 Nutrients
 Organelles
Plant cell parts
Plant cells may contain some extra parts.
Chloroplasts (plant cells)
Chloroplasts which are disc shaped and contain
chlorophyll for photosynthesis.
Cell wall (plant cells)
A cell wall which is a strong outer layer to
support the cell and give it shape.
Vacuole (plant cells)
A vacuole where the plant cell stores sap (the
food that it has made; a mixture of sugars, salts
and water).
To summarize: (draw and
label this!)