The document discusses the key scientists who contributed to cell theory and lists the three main tenets of cell theory. It also provides an overview of the major organelles found in cells like the nucleus, mitochondria, chloroplasts, lysosomes, and describes their main functions. Additionally, it compares the structure and organization of plant and animal cells and provides an analogy between the parts of a cell and that of a fictional city called Grant City.
1. Who are the scientist that
have significant contribution
in the field of cell theory?
What are the 3 tenets
of cell theory?
2. Objectives of the lesson
The learners should be able to:
1. identify and describe the structure of major
and subcellular organelles
2. state the function of major and subcellular
organelles
3. compare the parts of the cell to the parts of
the city
3. How did you come up with your
answer?
What is the function of each picture
presented?
What can you infer?
5. Cell
All the pocesses that occur within an organism
are supported by the cell. The cell contains
different parts called organelles, which carry out
different functions. The fine detail of the cell
(which may be revealed by an electron
microscope) is called the cells ultrastructure.
Organelles perform different functions within a
cell. This is called division of labor.
6.
7. CELL MEMBRANE
•is a phospholipid bilayer
embedded with protein and
carbohydrates. It is
semipermeable which means it
controls the entry and exit of
certain substances.
•in the cell membrane are several
specialized fingerlike folds called
microvilli which mainly increase
the surface area of the cell.
8. CYTOPLASM
•it contains the semifluid substance called cytosol where
the different organelles are suspended.
•within the cytosol are different substances such as
electrolytes (substances that produce electrically
conducting solutions), metabolites (substances
produced during metabolism), ribonucleic acid (RNA)
and synthesized proteins.
•the site of many physiological processes such as
glycolysis (conversion of glucose into another form)
and protein and fat synthesis.
9. CYTOPLASM
•it is where the molecules first
pass through after entering or
before exiting the cell membrane
•appears to have no form.
However, it does have a structure
due to the presence of
cytoskeleton.
•it has 3 major filaments: the
microfilament, microtubule and
intermediate filament
10. CYTOPLASM
•microfilament - has a diameter of about 7 nm and
mainly composed of contractile protein called actin.
•microtubule - diameter of about 25 nm and composed
of globular proteins called tubulins; help form the
shape of the cell.
•intermediate filament - about 10 nm and most stable
and the least soluble constituent of the cytoskeleton;
provides tensile strength in the cell
•Tensile Strenght - refers to the maximum stress that an
object can withstand before it breaks.
11.
12. CENTRIOLES
• during cell division, the microtubules
eventually arrange themselves in a
specific manner to form centrioles.
• these centrioles come in pairs and are
at right angles with each other.
• they help in the separation and
transfer of the replicated genetic
materials in the cells called
chromosomes.
• visible only in actively dividing animal
cells, because they are involved in the
development of spindle fibers.
13. NUCLEUS
•serves as a control center of the cell, because it is
where most of the genetic processes take place.
•it has several parts
• nuclear envelope - boundary of nucleus, composed of the
outer and the inner nuclear membrane.
• perinuclear space - between the membranes
• nucleoplasm - inside the nuclear envelope. Within the
nucleoplasm are strands of chromatin, which is a
combination of deoxyribunucleic acid (DNA) and proteins
• nuclear pores - where substances move in and out of the
nucleus.
14. NUCLEUS
•the information in the chromatin strands enables the
nucleus to control the activities of the cell.
•The DNA in the chromatin strands is the basis for the
duplication of new genetic materials. This duplication
ensures that new cells formed during cell division will
have genetic materials of their own.
• if the nucleus were absent, the cell would lose its
ability to produce new cells and proteins. (mature RBC
has no nucleus, 120)
15.
16. NUCLEOLUS
•membrane-free organelle found
inside the nucleus
•usually spherical in shape
•important in creating the
ribosomes, which are the site of
protein synthesis
•the absence of nucleolus will
compromise the process of
protein production because there
is none that can produce the
ribosomes.
17. RIBOSOMES
•are small spherical organelles,
composed of two subunits,
which can be found Rough
Endoplasmic Reticulum (and
also in the cytoplasm and in
mitochondria, and other
places). Ribosomes translate
genetic information in the
form of mRNA into proteins.
18. ENDOPLASMIC RETICULUM
•is found near the nucleus and is made up
of a number of flattened sacs called
cisternae, which are continuous with the
nuclear envelope.
•The Rough Endoplasmic Reticulum is
named such because it has a lot of
ribosomes on its outer surface.
20. SMOOTH ENDOPLASMIC RETICULUM
•The Smooth Endoplasmic Reticulum however , does not have
ribosomes. The Rough ER transports proteins that are
synthesized in the ribosomes while the Smooth ER
synthesizes Lipids.
21. GOLGI BODIES
•the same with ER, membrane-bound Golgi bodies also
consist of cisternae
•two faces (part facing the ER is called cis face, whereas
one facing the cytoplasm or the cell membrane is called
the trans face)
•responsible for the modification of proteins received
from the ER. These proteins are then transported in
vesicles around the cell. Also, its enzymes manufacture
and attach carbohydrates and proteins or lipids.
23. LYSOS0MES
•are membrane- bound spherical sacs which contain
hydrolytic enzymes (proteins that use water to break down
substances) ; use to digest food, recycle old components of
the cell, and kill invading microorganism.
•The white blood cells have many lysosomes that dispose
bacteria.
•The lysosomal membrane contains a special carbohydrate
covering its inner surface. This prevents the lysosome from
releasing the hydrolytic enzymes all at one. If this happens,
the cell may be killed. This why lysosome is also called the
suicide bag of the cell.
25. MITOCHONDRIA
•a double membrabne organelle
•outer membrane serves its covering, while inner membrane is
folded many times to create the cristae
•inside cristae is the matrix that contains different enzymes
•also found in the mitochondrion are circular molecules of
DNA and ribosomes
•1000-2000 mitochondrion in a typical animal liver cell
•responsible for producing adenosine triphosphate
(ATP), the energy currency of the cell
27. FLAGELLA AND CILIA
•are appendages responsible for locomotion of cells
•their locomotive action is due to the specialized arrangement
of microtubules
•both have central core called the axoneme, which is
sorrounded by an extension of the cell membrane
•axoneme is connected to the basal body, which is identical to
the appearance of the centriole
•flagellum - moves a whiplike manner, such as that Euglena, a
protist
•cilia - require power and recovery strokes, as in the swimming
movement of Paramecium, a protist
28.
29. FLAGELLA AND CILIA
•In humans, the flagella and
the cilia are important in
reproduction. In males,
sperm cells have flagella that
enable them to swim. A
sperm cell uses its flagellum
to reach the egg. In females
the cilia in the fallopian tubes
move the egg or embryo
toward the uterus.
30.
31. CELL WALL
•an additional cell covering in
plant cells. Located outside the
plasma membrane & primarily
made of cellulose (a
polysaccharide, which is a su
bstance composed of a long
chain of carbohydrates).
•mantains the shape of the plant,
protects the cell, and helps
regulate the cell's uptake of
32. •peptidoglycan - composed of amino acids and
sugars. The peptidoglycan in the cell walls of
bacteria give their structure and provide
protection. The presence of such can be
identified using a Gram-positive bacteria
(those showing a darker color in the
microscope) have thicker layers of
peptidoglycan than Gram-negative bacteria
(those showing a lighter color)
33. •chitin - nitrogen-containing polysaccharide
similar to cellulose forms a transparent
substance. Chitin in the cell wall fungi cells
seves as structural support
•some cells in plant roots have extensions. These
are specialized structures called root hairs.
•root hairs increase the surface area of the roots
for better absorption of water and minerals.
34. CHLOROPLAST
•a double-membrane organelle. Inside the chloroplast is the
stroma, a colorless fluid surrounding several grana.
•Each granum contains several stacks of thylakoids that
contain chlorophyll, which is the green pigment responsible
for capturing light energy during photosynthesis and for
plant's green color.
•lumen - space inside the thylakoid, which serves as the site of
several reactions during photosynthesis
•each granum is connected to one another via one another
the intergrana thylakoids or the stroma thylakoids.
•has DNA similar to that bacteria
35.
36. VACUOLE
•central vacuole - occupies the largest space in mature
plant cells which is sorrounded by a membrane called
tonoplast
•in animal - serves as the temporary storage of
substances
•in plants - maintain turgor pressure to keep the cell
from wilting
•turgor pressure - pressure exerted onto the wall by
water moving into the cell
39. Difference Between Animal and Plant Cell
ANIMAL CELL PLANT CELL
Comparatively smaller in size Usually larger in size
Enclosed by a thin plasma membrane Enclosed by a rigid cell wall in addition to
Plasma membrane
Often changes its shape Cannot change its shape
Plastids are usually absent Plastids are present
Often contains many small vacoules Mature plant cell contains large central
vacuole
Nucleus usually lies in the center Nucleus lies on one side of the cytoplasm
Centrioles are practically present Centrioles are normally absent except for
lower plant forms
Lysosomes are always present in animal cells Lysosomes are present
40. Difference Between Animal and Plant Cell
ANIMAL CELL PLANT CELL
Researved food in form of glycogen Researved food in form of starch
Cannot synthesize all amino acids, co-
enzymes and vitamins required by them
Synthesize all amino acids, co-enzymes and
vitamins required by them
Spindle formed during cell division is
aphiastral (has an ester in each pole)
Spindles formed during cell divisions in
anastra (without asters on the opposite side
Cytokinesis occurs by construction of
furrowing
Cytokinesis occurs by cell plate method
Animal cell lacking contractile vacuole
usually burst if placed in hypotonic solution
Plant cell does not burst if placed in
hypotonic solution due to the presence of
cell wall
41. CELL CITY ANALOGY
Cell City
In a far away city called Grant City, the main export and production product is the steel
widget. Everyone in the town has something to do with steel widget making and the entire
town is designed to build and export widgets. The town hall has the instructions for widget
making, widgets come in all shapes and sizes and any citizen of Grant can get the instructions
and begin making their own widgets. Widgets are generally produced in small shops around
the city, these small shops can be built by the carpenter's union (whose headquarters are in
town hall).
After the widget is constructed, they are placed on special carts which can deliver the widget
anywhere in the city. In order for a widget to be exported, the carts take the widget to the
postal office, where the widgets are packaged and labeled for export. Sometimes widgets
don't turn out right, and the "rejects" are sent to the scrap yard where they are broken down
for parts or destroyed altogether. The town powers the widget shops and carts from a
hydraulic dam that is in the city. The entire city is enclosed by a large wooden fence, only the
postal trucks (and citizens with proper passports) are allowed outside the city.
42. CELL CITY ANALOGY
Match the parts of the city (underlined) with the parts of the cell.
1. Mitochondria ___________________________________________
2. Ribosomes _____________________________________________
3. Nucleus ________________________________________________
4. Endoplasmic Reticulum ___________________________________
5. Golgi Apparatus _________________________________________
6. Protein ________________________________________________
7. Cell Membrane __________________________________________
8. Lysosomes ______________________________________________
9. Nucelolus _______________________________________________
10. Cell ______________________________________________
43. APPLICATION
Create your own analogy of the cell using a different
model. Some ideas might be: a school, a house, a
factory, or anything you can imagine.