4. Cell Theory
• All living things are made of cells
• Cells are the basic units of structure and
function of living things
• Living cells only come from other living
cells.
5. Overview
• In the same way there are different kinds
of cells inside you, different organisms
have different types of cells. Trees have
different cells than you and so do
monkeys. Each of those cells is different in
some way.
6. Cells and Organelles help
perform homeostasis
Homeostasis
Is the process of any
living thing that
allows it to live and
regulates its
internal
environment so as
to maintain a
stable, constant
condition.
Example: You get
hot and sweat!
7.
8. Oraganelles
• ORGANELLES mean little
organs. Basically this means that
organelles have specific roles to play in
how cells work just like organs help the
body to function properly as a whole.
20. Golgi Body
• a set of flattened,
membrane-
bound sacs that
serves as the
packaging and
distribution
center of the cell
21. Key Terms
• Organelles-structures that make up a cell
• Cell Wall-outer most part of a cell
• Cell Membrane-just inside the cell plant
wall which forms the outer covering of the
cell
• Nucleus-brain of the cell
22. Vocabulary
Cell Membrane: The purpose of the cell membrane is to hold
the cell together. It keeps all of the pieces, like the organelles
and the CYTOPLASM, inside.
Cell Wall: Cell walls help the plant maintain its shape. Walls
also help the plant keep its structure consistent
Nucleus: The NUCLEUS is like the brain of the cell. If you
take the nucleus out of a cell it dies. It is the thing that tells
every part of the cell what to do. It even tells the cell when to
divide.
Endoplasmic Reticulum: The purpose of the ER is
to collect proteins and create something called
steroids and store ions
23. More Words To Know
Vacuoles: Vacuoles are bubbles that float in the cell.
Those bubbles store the different molecules a cell needs
to survive. Some contain food and others hold oil. There
are even vacuoles that hold onto waste products.
Ribosomes: Ribosomes are the protein builders of the
cell. When they build proteins, scientists say that they
SYNTHESIZE the proteins. Ribosomes are found either
floating around in the CYTOPLASM or attached to the
Endoplasmic Reticulum (ER). The floating ribosomes
synthesize proteins that will be used inside the cell. The
ribosomes attached to the ER make proteins that will be
used inside the cell AND sent outside the cell.
24. Vocabulary
Mitochondria: The big thing you need to
remember about MITOCHONDRIA is that they are
the cell's little powerhouses. They are the thing that
lets cells survive. Their whole purpose is to break
down food molecules so that the cell has the energy
to live.
Chloroplasts: Chloroplasts are very much like
mitochondria. The big difference is that instead of
taking food and breaking it down into energy,
chloroplasts take energy from the sun and create
food.
25. Vocabulary
Lysosome: Lysosomes combine with the food taken
in by the cell. The enzymes in the lysosome bond to
the food and start to digest it.
28. Plant cells
• Plant cells have different structures than animal cells
• . Plant cells have something called a CELL WALL while
animals do not.
• Plant cells have an organelle called a CHLOROPLAST
that takes energy from the sun and converts it into
sugars.
• Does your body make sugar from the sun or do you get it
from food?
29.
30. Animal Cells
• Animal cells organize the body. You have brain cells,
stomach cells, bone cells, and many other types of cells.
Each is different from the others.
• Nerve cells conduct electrical impulses through the body.
There are cells in your intestine that absorb nutrients
from the food you eat. Stomach cells secrete an acid to
digest your food
• Do you think that your skin cells can absorb the nutrients
from your lunch? Why not?
32. Eukaryotic vs. Prokaryotic Cells
• Eukaryotic Cells:
– Bigger than Pro cells
– Have a nucleus
Prokaryotic Cells:
-Usually smaller than Eu cells
-Have NO nucleus
