Transcript What is a Cell?

Cell Anatomy
Cell Parts & Their Functions
What is a Cell?
A cell is the smallest unit that is
capable of performing life functions.
It is the basic unit of living things.
Cell Theory
• All living things are made up of cells.
• Cells are the smallest working units of all
living things.
• All cells come from preexisting cells through
cell division.
Examples of Cells
Amoeba Proteus
Plant Stem
Bacteria
Red Blood Cell
Nerve Cell
Cell Organelles
• Cell Parts are referred to as organelles.
Cell Wall
• Found in plant cells & some bacteria (not animal cells)
• Supports & protects the cell
Cell Wall
Cell Membrane
• Protective layer around all cells (both plant and animal)
• Allows food and oxygen into the cell and moves waste products
out of the cell
Cell Wall
Cell Membrane
Cytoplasm
• Space found inside of the cell (gel-like stuff that fills
the cytoplasm is called the cytosol)
• Surrounded by cell membrane
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
• Contains instructions (genes) for everything cell does (found in
the DNA)
• Strands of DNA form our chromosomes
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
Ribosome
• Each cell contains thousands of these
• Make proteins (structures that do certain jobs for the cell)
– (Think of it like a brick yard, it makes the things that cell is made
of)
• Found on ER & floating throughout the cell
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
Ribosome
Endoplasmic Reticulum
(ER for Short)
• Moves materials around in cell
–
Like a highway
• Smooth ER: doesn’t have (lacks) ribosomes
• Rough ER : ribosomes embedded (fixed) on the surface
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
Ribosome
ER
Mitochondrion
• Releases energy from food
– Energy/Power Plant of the cell
• Plural form is called the mitochondria
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
Ribosome
ER
Mitochondrion
Chloroplasts
• Found only in plant cells
• Contains green chlorophyll (why plants look green)
• Where photosynthesis (chemical reaction) takes place
– Helps plant cells make food
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
Ribosome
ER
Mitochondrion
Chloroplasts
Vacuole
• Temporary storage spaces; there are two types
– Central vacuole- found only in plants and contains water solution (helps
plants maintain—keep– their shape)
– Lysosome-found in both plant and animals cells, gets rid of wastes
(garbage disposal of the cell)
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
Ribosome
ER
Mitochondrion
Chloroplasts
Vacuoles
Golgi Body
• Protein 'packaging plant‘ (sometimes called the Golgi
Apparatus)
• Move materials into the cell
• Move materials out of the cell
Cell Wall
Cell Membrane
Cytoplasm
Nucleus
Ribosome
ER
Mitochondrion
Chloroplasts
Vacuoles
Golgi Body
Make a Cell
• Your assignment:
– We will make a model of the cell using the paper plate as the
basis of your cell.
– You need to decide if you want to make a plant cell or an
animal cell. This is a project, so it needs to look presentable
(which means no pencil and colors on the diagram)!
– You must have a diagram of your cell on the front of the
plate with the following organelles: nucleus, cell membrane,
cytoplasm, ribosome, endoplasmic reticulum, mitochondrion,
lysosome, and Golgi Apparatus (body)—if you have a plant
cell, you must also have a chloroplast and cell wall
– On the back of your plate, you must define IN YOUR OWN
WORDS what each organelle does; if you chose the animal
cell, you must also include the chloroplast and cell wall in your
list (note that they are only found in plant cells)
Bibliography
• http://www.scienceclass.net/PowerPoints/Cell_structure_functio
n.htm
• Glencoe Life Structure Book A
Thoughts from Yesterday…
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
What splits the cells?
Is there such a things as a “god” cell?
What is the smallest component in a cell?
How is an apple living? I know that it is the
cells, but how are they “living”?
With a stem cell, can you make a clone?
Can you mix DNA successfully?
How did they know what to name all these
things?
How did they discovery them (cells)?
Can you have a clone of yourself?
How do white blood cells fight bacteria and
other sicknesses?
Is our brain just another body part or are we
our brain?
If your parents are short and you are short
how did cells know that you would be short?
What’s the difference between DNA and a
cell?
If you have the same blood type as someone
else, can you have blood cells inserted into your
body?
Are there different cells?
•
•
Crazy that we can re-grow/create a part of
our bodies using only a stem cell.
Viruses are not living and a lot more things
are living (than I thought). It’s neat that
they have to take over you and use you as a
host.
In order to grow or heal yourself, your cells
have to split.
I didn’t know that babies were just a bunch
of cells before they turned into a baby.
Cells are the smallest working units of living
things and that all living things are made of
cells.
Can’t believe that something as big as living
creatures is run by something as small as a
cell!
I didn’t know that cells divided to make more.
Your brain tells cells to split and make more.
All living things are made of cells and they
are really important.
Didn’t know that cells could “eat” each other.
•
I didn’t know that cells have “brains”!
•
•
•
•
•
•
•
•