This document provides information about cell structure and function. It begins by outlining cell theory, including that all living things are composed of cells, cells are the basic units of structure and function, and cells only come from existing cells. It then discusses cell diversity in shape, size, and function. The rest of the document describes specific parts of eukaryotic cells like the nucleus, mitochondria, chloroplasts, as well as comparing plant and animal cells. Key cellular structures and their functions are defined.

1. Chapter 4
Cell Structure and Function

2. Cell Theory
 All living things are composed of one or
more cells.
 Cells are the basic units of structure and
function in an organism.
 Cells come only from the reproduction of
existing cells.

3. Cell Diversity
 Cells vary in shape,
size and internal
organization.
 All cells have a
specific job to do and
look and function the
best for that job.

4. White blood
cells
Stem cells

5. Nerve Cells
Heart cells

6. Skin cells
Plant cells

8. Important Vocabulary
 Many cells have a variety of internal structures
called organelles or mini organs.
 Most cells are surrounded by a cell membrane.
 Many cells have a large organelle called the
nucleus.
 Cells that contain organelles and a nucleus are
called eukaryotic cells.
 Cells that DO NOT contain organelles and a
nucleus are called prokaryotic cells.

10. What’s the difference
here?
 Let’s compare three items: a eukaryotic cell,
a prokaryotic cell and a virus.
 What are the similarities?
 What are the differences?

15. Flu virus

16. T4 Bacteriophage

17. HIV

18. Prokaryotes Vs. Eukaryotes Vs.
Viruses
 No membrane  Nucleus with • No nucleus
bound nucleus membrane
 Only plants have • No membranes
 Has a cell wall cell wall
 Only a few • No organelles
 Contains many
organelles or organelles • Cannot
none at all.  Has a lipid bi- reproduce on
 Has a capsule layer membrane its own
surrounding it surrounding it.
 Specialized by • Generally not
 Three main thousands of considered
types. different sizes alive by most
and shapes.
standards

19. Parts of the Eukaryotic
Cell
 Cell Membrane
 Cytoplasm (cytosol)
 Mitochondria
 Ribosome
 Endoplasmic reticulum (rough and smooth)
 Golgi apparatus
 Lysosome
 Cytoskeleton
 Cilia and Flagella
 Nucleus
 Nucleolus
 Cell wall
 Vacuole
 Chloroplast

21. Plant Cells Vs. Animal Cells
 Contain chloroplasts for  No cell wall
photosynthesis  No chloroplasts
 Have a cell wall to maintain
structure and rigidity  Contain lysosomes and
 Usually do not contain peroxisomes
lysosomes and peroxisomes  Contain cilia and/or
 Cells are square and rigid or flagella
geometric shaped  Cells are fluid and flexible,
 Limited movement many shapes
 Have one large central
vacuole
 Cells can move around.
 Has small vacuoles

23. Parts of Eukaryotic Cell
You are required to know the parts, what
they look like and their function for the
test!

24. Cell Membrane
 The cell membrane is selectively permeable
which means some substances can cross and
others cannot cross.
 Cell membranes are made of primarily lipids and
proteins.
 Cell membranes are made of a lipid bi-layer.
 A cell membrane is called a fluid mosaic because
it behaves more like a liquid than a solid.
 It is flexible and provides an effective barrier and
transport function.

26. DRAW
THIS!

27. Cytoplasm
 This lies between the
cell membrane inside
of the cell.
 It is a fluid that all the
organelles float in.
 It is sometimes called
the cytosol.

28. Mitochondria
 Mitochondria are the
powerhouses of the cell.
 Mitochondria create ATP for
the cell to use as energy.
 One cell many have
thousands of mitochondria
depending on its function.
 Mitochondria have two
membranes and have their
own DNA which only comes
from the mother.

30. Ribosomes
 Ribosomes are the most
numerous of the cell’s
organelles.
 Ribosomes are made of
proteins and RNA.
 Ribosomes are responsible
for creating proteins.
 Ribosomes are found free
in the cytoplasm and also
attached to the rough ER.
(endoplasmic reticulum)

32. Endoplasmic Reticulum
 The ER comes in two varieties, the rough ER and
the smooth ER.
 The rough ER contains ribosomes and makes
proteins.
 The smooth ER does not contain ribosomes and
makes lipids such as steroids.
 The rough and smooth ER are sometimes attach to
each other.
 Both ER are involved in cell product transport of
proteins and lipids.

34. Nucleus
Ribosomes

35. Golgi Apparatus
 The golgi is the
processing,
packaging and
transport system.
 It is a system of
membranes that work
closely with the ER.
 The golgi modifies the
products for transport
throughout the cell.

38. Lysosomes
 Lysosomes contain
enzymes that help
digest proteins,
carbohydrates, lipids,
DNA and RNA.
 These enzymes can
also digest old
organelles, viruses
and bacteria.
 Lysosomes are rare
in plant cells.

40. Cytoskeleton
 Cytoskeleton’s are made
of two parts: the
microtubules and the
microfilaments.
 The microtubules assist
in cell division by moving
the cells apart.
 Microfilaments are made
of protein and help with
muscle contractions.
 Both help support the cell
and give structure but do
allow for movement.

41. Cilia and Flagella
 Some cells have flagella.
They usually only have
one.
 Many cells have cilia
Cilia
which can number in the
thousands.
 A flagella is like a whip.
 Cilia are like tiny
paddles.
Flagella
 Cilia and flagella are
made of microtubules.

42. Nucleus
 The nucleus is
surrounded by a
membrane called
the nuclear
envelope.
 The nucleus
contains all the DNA
for the cell.
 It directs all the
activities of the cell.
 The nuclear
envelope contains
pores so that RNA
can pass into the
cytoplasm during
protein synthesis.

44. Nucleolus
 The nucleolus is
found inside the
nucleus.
 It is responsible for
making the
ribosomes.
 There is usually only
one.

45. Cell Wall
 Found in plant cells
and bacteria only.
 Not found in animal
cells.
 Helps maintain
structure and
protection.
 Does contain small
pores to move water
and oxygen and
carbon dioxide in and
out.

46. Vacuoles
 These are fluid filled
and store many
different things such
as water, waste,
enzymes and
poisons.
 In plants vacuoles
take up 90% of the
space.
 Vacuoles are small in
animal cells.

48. Chloroplast
 This also called a plastid.
 Chloroplasts have their
own membrane and their
own DNA.
 Chloroplasts are found
only in plant cells and
some protists. (little
animals)
 Chloroplasts do
photosynthesis and
contain chlorophyll which
make them green.
 Photosynthesis creates
sugar from sunlight for
the plant to use.