cell structure and functions

1. Cell
WHY DO WE NEED TO DISCUSS THIS?
Structure &
functions

2. The principal Parts of a cell are:
The Cell Membrane
The Protoplasm and its organelles;
and
The nucleus

4. CELL MEMBRANEAll cells and their protoplasmic contents are surrounded by a
thin layer called plasma membrane.
The plasma membrane also serves as a boundary between the
environment and the inside of the cell. Furthermore, the membrane
gives form to cells.
Because of the structure of the cell membrane, it
is semipermeable and selectively permeable. It allows
only chosen substances to enter and leave the cell.
The plasma membrane also connects one cell to
two or more adjacent cells. At times it can serve as an
organ.

5. protoplasm and its
organelles
The plasma membrane encloses a mass of
jellylike material called protoplasm. The
protoplasm is a colorless or somewhat grayish,
translucent, viscous substance that is capable of
flowing.
Various organelles, also called little
organs, are also present in the protoplasm. Some
of them are visible under the light microscope;
others are not.

6. Cytoplasm and
karyoplasm
If a nucleus is present in a cell, the
protoplasm is differentiated into two: (1)
cytoplasm, the protoplasm lying outside the
the nucleus; and (2) karyoplasm or
nucleoplasm the protoplasm inside the
nucleus.

7. Mitochondria
Mitochondria (sing., mitochondrion)
are rod-shaped bodies in the cytoplasm.
They vary in number and shape. They are
centers of cellular respiration, a process in
which energy-rich adenosine triphosphate, a
compound in cells that functions in energy
storage and transfer is produced.
POWER HOUSE OF THE CELL

8. ribosomes
All throughout the cytoplasm are
tiny dotlike structures called ribosomes.
These organelles are composed of nucleic
acids (RNA) and proteins. They are numerous
in cells that manufacture great amounts of
protein. The synthesis of proteins occurs in
ribosomes.
Protein factories of the cell
ribosomes

9. Endoplasmic reticulum
Ribosomes are often attached to
long strands of membrane called
endoplasmic reticulum which forms a
network of tiny canals through the cell.
These canals are formed by two parallel
membranes. They connect the nuclear
membrane and plasma membrane, thus
serving as passageway for food substances.
Manufacturer and shipper of the cell

10. Endoplasmic reticulum
Manufacturer and shipper of the cell
Rough Endoplasmic
Reticulum, the outer
surfaces of the
membranes are lined
with ribosomes,
resulting granular
appearance. The rough
ER bears ribosomes that
aid in protein synthesis.
Smooth Endoplasmic
Reticulum have no
ribosomes. The smooth
ER functions in the
synthesis of lipids, drug
detoxification, and
attachment of receptors
on the cell membrane
proteins

11. Golgi bodies
In 1898, an Italian scientist, Camillo Golgi (1843-1926), observed a
series of vesicles in the nerve cells of an owl. These vesicles were named Golgi
bodies, after him.
Golgi bodies (Golgi complex/Golgi apparatus) are associated with many
functions. They are also believed, to modify, process, and package
macromolecules such as proteins for secretion after they are released from the
ER. During the process, certain proteins are surrounded by pieces of the
membrane that detach from the Golgi body. These pieces form tiny, membrane-
bond spheres called vesicles.
The vesicles carry the protein to the plasma membrane. Each vesicle
then joins with the plasma membrane and pours its contents out of the cell.
Packaging counters of the cell

12. Golgi bodies
Packaging counters of the cell

13. vacuoles
Vacuoles are fluid-filled cavities
surrounded by membrane regulates the
molecular traffic between the vacuole and
the cell substances.
Vacuoles in plant cells store large
amounts of water.
Tanks of the cell

14. Let’s
have a

15. Let’s have a
review!!
CELL
MEMBRANE

16. Let’s have a
review!!
PROTOPLASM AND
ORGANELLES

17. Let’s have a
review!!
CYTOPLASM VS.
KARYOPLASM

18. Let’s have a
review!!
CYTOPLASM VS.
KARYOPLASM

19. Let’s have a
review!!
MITOCHONDRIA

20. Let’s have a
review!!
RIBOSOMES

21. Let’s have a
review!!
ENDOPLASMIC
RETICULUM

22. Let’s have a
review!!
GOLGI
BODIES

23. Let’s have a
review!!
VACUOLES

24. lysosomes
Lyso means dissolving power, and
some means body. Lysosomes were
discovered only in 1952. It is also called as
suicidal bags as it helps in cell renewal and
break down old cell parts. The lysosome also
makes possible the destruction of
microorganisms such as bacteria such as
bacteria and othr harmful foreign bodies
taken in by the cell through its membrane.
Suicide bags of the cell

25. Centrosomes and
centrioles
A centrosome is a mass of dense in
protoplasm with structures called centrioles
at the center. The centrioles, as a part of
the cytoplasm, duplicate and form at the
center for spindle fiber formation during cell
division.
Helpers In cell division

26. cytoskeleton
A cytoskeleton supports the internal
system of a cell and also gives the cell its
shape. It consists a microtubules– provide
pathway for cellular molecules to move
about.
Framework of the cell

27. Organelles
peculiar to
plant cells

28. Cell wall
The cells of plants, fungi, and some
single-celled organisms are protected and
supported by a rigid cell wall, which lies
outside the plasma membrane and is
composed mainly of cellulose.

29. PRIMARY CELL WALL- is the outer layer. It
expands as the cell grows.
SECONDARY CELL WALL- develop inside the
primary cell wall. This new layer adds strength to the
wall.
MIDDLE LAMELLA- separates the two cell walls
of adjacent cells which is composed of a jelly-like
polysaccharide called pectin.
PLASMA MEMBRANE

30. chloroplasts
Chloroplasts are the chromoplasts
containing the green coloring pigment called
chlorophyll which is essential in
photosynthesis.

31. chromoplasts
Chromoplasts also contain various yellow
or orange pigments called carotenoids. These
chromoplasts also give many flower and fruits
their characteristic yellow or orange color. The
chromoplasts in tomatoes contain red pigment,
rheodoplast. This pigment makes tomatoes red.

32. leukoplasts
Leukoplasts serve as food storehouses in many plant
cells.

33. nucleus
It contains the genetic material DNA,
which determines the characteristics of a
cell and directs the production of proteins.
The DNA molecules in the nucleus are found
in nucleoplasm or in a definite structure
called chromosomes.
Control center of the cell

34. chromosomes
The chromosomes are originally
chromatin materials that contain the
hereditary information of the cell. When the
cell reproduces or divides, the chromatin
becomes visible as shortened chromosome
strands.

35. Nuclear membrane
The bilayer membrane, which
protects the nucleus by surrounding around
it and acts as a barrier between the cell
nucleus and other organs of a cell.

36. nucleolus
Chromatin inside the nucleus is
condensed into a darker region called
nucleolus, a structure involved in the
production of ribosomal RNA (rRNA)
that translate messenger RNA (mRNA)
to produce proteins.

37. Questions?

38. ACTIVITY 2

39. ACTIVITY
2
Outer membrane of cell that controls
movement in and out of the cell
Contains genetic
material - DNA
Make proteins
Transports undigested material
to cell membrane for removal
Move
materia
ls out of
the cell
Most commonly found
in plant cells & bacteria
Where
photosynthesis
takes place
Protoplasm
lying outside
the nucleus
Membrane-bound sacs for
storage, digestion, and waste
removal
Contains RNA to build
proteins

40. 26.
Outer membrane of cell that
controls movement in and
out of the cell
Contains genetic
material - DNA
Make proteins
Transports undigested
material to cell membrane
for removal
Move materials
out of the cell
27.
28.
29.
30.

41. Most commonly found in
plant cells & bacteria
Where
photosynthesis
takes place
Protoplasm lying
outside the nucleus
Contains RNA to
build proteins
Membrane-bound sacs
for storage, digestion,
and waste removal

42. CHANT
CELL

43. ASSESSMENT

44. Instruction: Write the letter of the correct answer.
a. Cytoplasm
b. Nucleolus
c. Chromosomes
d. Ribosomes
e. Chromoplasts
f. Nuclear membrane
g. Cell wall
h. Vacuoles
i. Rough ER
j. Cytoskeleton
k. Lysosomes
l. Chloroplasts
m. Nucleus
n. Smooth ER
o. Leukoplasts
p. Cell membrane
q. mitochondria
1. Contain the hereditary information of the cell
2. It hard wall that protects the cell membrane; commonly found on plants and single-celled
organisms.
3. Supports the internal system of a cell and also gives the cell its shape.
4. It contains the genetic material DNA, which determines the characteristics of a cell and
directs the production of proteins.
5. A type of endoplasmic reticulum that has no ribosomes.
6. The protoplasm lying outside the nucleus.
7. Connects one cell to two or more adjacent cells; at times it can serve as an organ.
8. Serve as food storehouses in many plant cells.
9. A structure involved in the production of ribosomal RNA (rRNA) that translate messenger
RNA (mRNA) to produce proteins.
10. It is also called as suicidal bags as it helps in cell renewal and break down old cell parts.
11. It stores large amounts of water in the cell.
12. The tiny dotlike structures that is responsible for protein synthesis.
13. They are centers of cellular respiration, a process in which energy-rich adenosine
triphosphate, a compound in cells that functions in energy storage and transfer is
produced.
14. The bilayer membrane, which protects the nucleus by surrounding around it and acts as a
barrier between the cell nucleus and other organs of a cell.
15. Contains the green coloring pigment called chlorophyll which is essential in
photosynthesis.

45. 1. Contain the hereditary information of the cell.
2. It hard wall that protects the cell membrane; commonly found on plants and single-celled organisms.
3. Supports the internal system of a cell and also gives the cell its shape.
4. It contains the genetic material DNA, which determines the characteristics of a cell and directs the
production of proteins.
5. A type of endoplasmic reticulum that has no ribosomes.
6. The protoplasm lying outside the nucleus.
7. Connects one cell to two or more adjacent cells; at times it can serve as an organ.
8. Serve as food storehouses in many plant cells.
9. A structure involved in the production of ribosomal RNA (rRNA) that translate messenger RNA
(mRNA) to produce proteins.
10. It is also called as suicidal bags as it helps in cell renewal and break down old cell parts.
11. It stores large amounts of water in the cell.
12. The tiny dotlike structures that is responsible for protein synthesis.
13. They are centers of cellular respiration, a process in which energy-rich adenosine triphosphate, a
compound in cells that functions in energy storage and transfer is produced.
14. The bilayer membrane, which protects the nucleus by surrounding around it and acts as a barrier
between the cell nucleus and other organs of a cell.
15. Contains the green coloring pigment called chlorophyll which is essential in photosynthesis.
a. Cytoplasm
b. Nucleolus
c. Chromosomes
d. Ribosomes
e. Chromoplasts
f. Nuclear membrane
g. Cell wall
h. Vacuoles
i. Rough ER
j. Cytoskeleton
k. Lysosomes
l. Chloroplasts
m. Nucleus
n. Smooth ER
o. Leukoplasts
p. Cell membrane
q. mitochondria
C. CHROMOSOMES
G. CELL WALL
M. NUCLEUS
N. SMOOTH ER
A. CYTOPLASM
P. CELL MEMBRANE
O. LEUKOPLASTS
B. NUCLEOLUS
K. LYSOSOMES
H. VACUOLES
D. RIBOSOMES
A. MITOCHONDRIA
F. NUCLEAR MEMBRANE
L. CHLOROPLASTS
J. CYTOSKELETON

46. THANK
YOU!!