2 Types of Cells: Prokaryotic and Eukaryotic
Prokaryotic-Also called bacteria.
World’s smallest cell.
Do not have a nucleus.
No membrane covered organelles.
Circular DNA
Eukaryotic Cells: What we have!
Complicated
internal structure
Contain a nucleus
Membrane covered
organelles
Linear DNA
Organelles – “Little Organs”
Cell structures that carry
out specific jobs in cells.
Parts of a Cell-Organelles
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Lysosomes
Golgi Apparatus
Chloroplasts
Chlorophyll
Cell Wall
Cell Membrane
Cytoplasm
Endoplasmic Reticulum
Ribosomes
Mitochondria
Vacuoles
Cytoskeleton
The structure and function of cells
• Characteristics of cells:
1. Cell wallSupport and protection, strong
and stiff. Made of cellulose.
Found only in plant cells.
2. Cell membraneDoorway of cell. In plants, just
inside cell wall. In animals, it is
the outer covering of the cell.
Made of phospholipids.
4 jobs of the cell membrane:
Support and protection for the cell
Openings called pores in the membrane allow
waste material to pass out of the cell.
Controls movement of things in and out of cell
Forms a barrier between the inside and
outside of the cell.
Nucleus: Control Center of the Cell
• Nucleus:
Control center or “brain” of the
cell that regulates or controls
all activities of the cell.
Contains cell’s genetic material.
Cytoplasm, Cytoskeleton and the Endoplasmic
Reticulum
Cytoplasm: Clear, thick, jellylike substance b/tween nucleus and cell membrane.
Constantly moves. Cell organelles located here.
Cytoskeleton : Web of proteins in cytoplasm. Acts as skeleton. Keeps cell
membrane from collapsing.
Endoplasmic Reticulum: Clear, tubular passageways in the cell through which
substances are transported. Proteins and fats made here and carried around the
cell.
Ribosomes
Attached to the surface of the endoplasmic reticulum.
Protein making sites of the cell.
The Cell’s Energy Factory-Mitochondria
Break down sugar and release
energy.
This energy powers the cell’s
organelles.
This process is called cellular
respiration.
Energy released by the
mitochondria is stored in the ATP.
(Adenosine Triphosphate)
The Cleanup Crew for the Cell
Lysosomes
• Involved in digestive activities of
the cell.
• Contain enzymes that break down
food.
• Digested food then passed on to
mitochondria to provide energy to
the cell.
•When old cell parts outlive their
usefulness, lysosomes “eat” them.
• This “energy” from an old cell part
is recycled back into the cell.
• 2 examples of lysosomes being
used: Frog’s tail, our fingers
The Cell’s Packaging Center
Golgi Apparatus or Complex
• Packages and
transports these
materials out of the
cell: Proteins
The Cell’s Storage Centers- Vacuoles
Vacuoles
Food, water, and waste are
stored in the vacuoles.
In plants, when the vacuoles are
full of water, they swell and make
the plant firm.
Plants Only!
Chloroplasts
• Energy producers for the cell.
• Contain chlorophyll, a green
substance involved in photosynthesis
that captures the sun’s energy.
• Captures energy of sunlight to
produce food for the plant cell.
• Glucose is the simple sugar
plants make for food during
photosynthesis.
A plant’s cell walls are made of a
sugar called cellulose.
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Classwork!
• Complete a DLCD (Draw, Label , Color, and
Define) of an animal and plant cell from
pages 56-57 in your science book.
• First draw or sketch out plant and animal
cell with pencil first.
• Next, label ALL parts of both cells and give
a BRIEF description of each on the back,
bottom, or sides of your DLCD.
• Last, please color both cells.
• Not homework. Put in folders at end of
class.