Download Discovering Cells

Looking Inside Cells
Enter the Cell
 Key Concept: A cell wall is a stiff layer
that helps to protect and support a plant
cell.
 Animal cells do NOT have cell walls.
 Many materials like oxygen and water
can pass through the cell wall.
Organelles in the Cytoplasm
 Key Concept: In the cytoplasm there are many
organelles that have a specific function.
 Animals Cell
Plant Cell
CYTOPLASM
 Cytoplasm- gel-like fluid
 Jell-o, hair gel
 Can you think of others?
 Key Concept: The cell membrane
controls what substances go into and out
of a cell.
 For a cell to live, the cell membrane must
let material pass in and out of the cell.
CELL WALL VS. CELL MEMBRANE
 The cell wall is only found in the plant
 The cell membrane is found in the cell wall and
the cell membrane
 Cell wall is like a wall of a house it is strong! The
cell wall is made of CELLULOSE….REMEMBER
THAT!
 The cell membrane is like a screen: it allows some
materials in and keeps others out.
Sail on to the Nucleus
 Key Concept: The nucleus is the control
center of the cell and directs all of the
cell’s activities.
 The nucleus is protected by a membrane
called the nuclear envelope.
 The nucleus holds genetic information.
Genetic information controls what the
cell does.
WHERE IS THE NUCLEUS?
What is the genetic information?
 The genetic information inside the
nucleus is called DNA (deoxyribonucleic
acid)
Nuclear Envelope
 Why do you think DNA has to be
protected by the nuclear envelope?
Nuclear Envelope
 The nuclear envelope
has holes called pores
that allows necessary
molecules to pass
between the nucleus
and the cytoplasm
ENDOPLSAMIC RETICULUM
 Endoplasmic Reticulum- Interconnected
network of thin folded membranes that form a
maze. It aids in the important production of
proteins and lipids (necessary fats)
RIBOSOMES
 Ribosomes- protein factory
 Factory – they link together amino acids, which
in turn make up proteins
 Why are proteins important?
GOLGI Apparatus
 Golgi apparatus- process, sort, and deliver the
proteins to where they need to go.
 Post Office, UPS
GOLGI Apparatus
 Golgi apparatus Some proteins are stored for later use
 Some are transported to other organelles within the cell
 Some are carried to the membrane
 Some are carried outside the cell
Vesicles
 Vesicles – Isolate and
transport molecules
 Vesicles are small sacks
that divide materials
from the rest of the
cytoplasm and take
things from place to
place
 Cells sometimes need to
isolate (separate) different
chemicals until they are
ready to be used
Proteins
Made
ER makes a
vesicle
around the
protein
Golgi makes
modifications
Protein
transported to
Golgi App.
Put into a
new vesicle
Held,
Transp.,
or
Secreted
MITOCHONDRIA/MITOCHONDRION
 Mitochondria- power house
 It supplies energy to the cell
 Battery, solar panel
 Can you think of others?
MITOCHONDRIA/MITOCHONDRION
 Mitochondria- Also has its
own separate DNA and
their own ribosomes
VACUOLES
 Vacuoles- Fluid filled sac used for storage by the
cell.
 Plant cell: one large vacuole. Like a swimming
pool
 Animal cell: many small ones like cupboards.
LYSOSOMES
 Lysosomes- rids the cell of
waste. (Like a garbage
disposal.)
 They contain enzymes and
defend the cell from
invading bacteria and
viruses.
 Lysosomes are mostly found
in animal cells
 Lysosomes also recyle
foreign or worn out parts
Centrioles
 Cylinder shaped organelles made of short
microtubules arranged in a circle
 Appear to help DNA divide during cell
division
Plant cells… Cell Walls and
CHLOROPLASTS
 Chloroplasts- capture sunlight for energy to
make food. (only in PLANTS)
 Like a solar panel
 Chloroplasts convert solar energy into chemical
energy through photosynthesis
 The outer cell wall supports, and gives
protection to the cell
Chloroplasts
 Chloroplasts also have
pigment (color)
 Only the chloroplasts that
have chlorophyll can carry
out photosynthesis
 The rate of photosynthesis
increases as the number of
chloroplasts with chlorophyll
increases
 That means: it happens faster
http://www.clearbiology.com/water-molecule-worksheet/
Cell Diversity
 Key Concept: The variety of structure in
cells reflects differences in cell function.
 Cells come in many shapes. The different
shapes help them to do different jobs.
 Some cells have organelles that others do
not. Give me examples and write them
down.