Download Adult stem cells

TOPIC 2: CELLS
Cells may have
different shape.
List the properties of living things
Is a river living organism? Why?
Is a TV living organism? Why?
Is a mushroom living thing? Why?
Metabolism
Response
Growth
Characteristics of life
Reproduction
Nutrition
Excretion
Types of microscope
Light microscope can magnify objects about 1000 times.
Electron microscope (EM): focuses beam of electrons through
specimen or onto its surface.
a. Scanning EM: it is used to study of detailed structure of the
surface of the cell.
b. Transmission EM: is used to study details of internal structure
of the cell.
Different
techniques in
microscope
• Scanning electron
microscope 580X
• Light microscope
• 230X
Different techniques
in microscope
• Differential
interference
contrast
micrograph 380X
• Transmission
electron
micrograph
9,375X
Organization of Life
Arrange the following words from largest
structure to smallest structure:
Atom
Protein
Plant Cell
Molecule
Virus
Mitochondria
Bacteria
Nucleus
Long Nerve Cell
Chicken Egg
Grain of rice
Cell size and scales
http://learn.genetics.utah.edu/content/begin/cells/scale/
THE CELL THEORY
1. All living things are composed of cells
2. The cell is the smallest unit of life
3. All cells come from pre-existing cells
HOW CAN WE GROUP CELLS ACCORDING
TO THEIR TYPE?
PROKARYOTIC CELLS
EUKARYOTIC CELLS
PROKARYOTIC CELL (DEFINITION)
- No true nucleus
- No membrane-bound organelles
- Ex. Bacteria
EUKARYOTIC CELL (DEFINITION)
- True nucelus
- Membrane bound organelles
- Ex. Animal cell, plant cell
• Bacterial colony at the tip of a needle.
CELL MEMBRANE
Parts of PROKARYOTIC CELLS
1. Cell membrane
2. Cytoplasm
3. Nucleoid (genetic material)
4. Cell wall
5. Ribosomes
Parts of PROKARYOTIC CELLS
6. Capsule
7. Pili
8. Flagella
9. Plasmid
What does the term “bacterial growth”
mean?
What are the conditions for bacterial
growth?
Is there any bacterium in your body?
Are all bacteria harmfull?
Classification of Bacteria
• According to shape
Eukaryotic cells
What are these cells?
Is it an animal cell or plant cell? Why? What
are the parts that you can identify?
EUKARYOTIC CELLS
1.
2.
3.
4.
5.
6.
7.
8.
Cell membrane
Cytoplasm
Nucleus
Ribosomes
Rough endoplasmic reticulum
Smooth endoplasmic reticulum
Golgi apparatus
Mitochondria
What are the diffreneces between the cell in
slide 4 and this cell?
EUKARYOTIC CELLS
Plants
9. Cell wall
10. Chloroplast
11. Vacuoles
12. Cytoskeleton
Animals
9. Lysosome
10. Centrioles
11. Vacuoles
12. Cytoskeleton
13. Cilia
14. Flagella
What does the eukaryotic cell cytoplasm
contain? Explain.
• Organelle name:
Nucleus
• Structure:
• Function:
• Label the parts of
the nucleus.
Structure: Nucleus is made of double membranes with
pores. It contains genetic material (chromatin)
What is the function of the nucleus? to cotrol all cellular
activities. E.g: protein synthesis
• Why are there pores on the nuclear membrane? To
allow molecules to enter and exit the nucleus. These
molecules carry messages to the organelles.
• Define chromatin. It is eukaryotic genetic material
which consists of DNA and protein.
• Organelle name:
rough endoplasmic reticulum
(rER) and smooth endoplasmic
reticulum (sER)
• Structure: It has flattened
membranous structure which
has ribosome on the
membrane.
• Function of rER: produce
proteins and transport them to
Golgi body.
• Structure-function relation:
folded membranes have more
surface area, more protein
syntheis takes place.
sER
• It produces lipid and transport these
proteins to the Golgi body.
• It has role in the synthesis of cell membrane.
Why?
• It stores Ca2+ in the muscle cell
Golgi body
• Organelle name: Lysosome
• Structure: Membrane bound vesicle.
• Function:
a. To digest old organelles, harmful chemicals, bacteria
b. Autolysis during development of embryo
• Organelle name:
• Vacuole
• Structure:
Mebrane bound
vesicle
Function:
a. To store food or
waste
b. To pump out
excess water
from fresh water
protist cells.
• Organelle name:
Mitochondria
• Structure:
Membrane bound
organelle. It has
double membranes,
inner membrane has
folded structure
• Function:
To supply energy
(ATP) to the cell by
breaking down of
sugar.
• Why is the inner
• Organelle name: Chloroplast
• Structure: It has double membranes, It contains chlorophyll
(green pigments)
• Function: to produce sugar by photosynthesis.
• What is photosynthesis? Name the three things which are
used in photosynthesis.
• Name a similarity between nucleus, mitochondrion and
chloroplast.
• Do all cells of a plant have chloroplast? Justify your
answer.
• Name of the cell part: cell wall
• Structure: cellulose
• Function: to protect cell against
water pressure in the plant cell.
• Organelle name: Ribosome
• Structure: Has two subunits, made of rRNA and proteins.
• Function: to produce protein
• What else do we need to produce protein?
SKELETON OF THE CELL
• Name of the
cell part:
cytoskeloton
• Structure:
protein fiber
• Function:
a. to give shape
to animal cells.
b. To transport
organelles in
the cell.
Muscle fibers for movement
• Organelle name: centrosome
• Structure: protein fibers
• Function: have role in cell division.
• They are found only in animal cells.
• Name of the cell
part: flagella
• Structure:
protein fiber
• Function:
movement
HOW CAN WE GROUP ORGANISMS
IN TERMS OF CELL NUMBER?
1- Unicellular organisms (one celled organism)
Ex. Bacteria and protisits
2- Multicellular organisms (many celled
organism) Ex. Plants, animals, fungi
EVOLUTION CONNECTION: Secondary
endosymbiosis is the key to much of protist
diversity
 The endosymbiont theory explains the origin of
mitochondria and chloroplasts.
• Eukaryotic cells evolved when prokaryotes established
residence within other, larger prokaryotes.
• This theory is supported by present-day mitochondria
and chloroplasts that
– have structural and molecular similarities to
prokaryotic cells and
– replicate and use their own DNA, separate from the
nuclear DNA of the cell.
© 2012 Pearson Education, Inc.
Evolution of eukaryotic cell
Stem cell
It is an unspecialized cell that can produce an
identical daughter cell and a more specialized cell that
undergoes differentiation.
Stem cells can be used for therapeutic purpuses.
Therapeutic cloning can produce stem cells with
great medical potential
 When grown in laboratory culture, stem cells can
• divide indefinitely and
• give rise to many types of differentiated cells.
 Adult stem cells can give rise to many, but not all,
types of cells.
 Embryonic stem cells are considered more promising
than adult stem cells for medical applications.
 The ultimate aim of therapeutic cloning is to supply
cells for the repair of damaged or diseased organs.
© 2012 Pearson Education, Inc.
 Embryo /fetus has stem cells (ES).
 Umblical cord has stem cells.
 Adult tissues have stem cells . Development of adult
stem cells is limited.
 Example: Stem cell from the bone tissue may develop
into heart muscle cell, heart muscle and nerve tissue.
© 2012 Pearson Education, Inc.
Figure 11.15
Blood cells
Adult stem
cells in bone
marrow
Nerve cells
Cultured
embryonic
stem cells
Heart muscle cells
Different culture
conditions
Different types of
differentiated cells
Cell size surface area volume ratio
• When surface area volume ratio is small, that
means surface area of the cell is not enough
and cell will divide.
Emergent properties
Group of cells can
perform more complex
function than a single
cell. This property is
called emergent
property.