CELL ORGANELLS Plasma membrane Protoplasm Cell wall Cell coat Mitochondria Endoplasmic reticulum Golgi bodies Ribosome Nucleus CONCLUSION REFRENCE All living organisms on Earth are divided in pieces called cells. There are smaller pieces to cells that include proteins and organelles. There are also larger pieces called tissues and systems. Cells are small compartments that hold all of the biological equipment necessary to keep an organism alive and successful on Earth.

1. CELL ORGANELLES
By
KAUSHAL KUMAR SAHU
Assistant Professor (Ad Hoc)
Department of Biotechnology
Govt. Digvijay Autonomous P. G. College
Raj-Nandgaon ( C. G. )

2. SYNOPSIS
 INTRODUCTION
 CELL ORGANELLS
1. Plasma membrane
2. Protoplasm
3. Cell wall
4. Cell coat
5. Mitochondria
6. Endoplasmic reticulum
7. Golgi bodies
8. Ribosome
9. Nucleus
 CONCLUSION
 REFRENCE

3. INTRODUCTION
All living organisms on Earth are divided in pieces
called cells. There are smaller pieces to cells that
include proteins and organelles. There are also larger
pieces called tissues and systems. Cells are small
compartments that hold all of the biological
equipment necessary to keep an organism alive and
successful on Earth.
DEFINATION
 In 1665 Sir Robert Hook discovered the cell.
 Loewy and Sickkevitz, 1963
“Unit of biological activity surrounded by a permeable
membrane and capable of self-reproduction in a
medium, free of other living systems.”
 Sir Rudolf Peters,1968
“The living cell is the most important invention in
nature.”

4. CELL ORGANELLES
DEFINATION
“Living structural organelles witch are present in
cytoplasm are known as cell organelles.”
Cell organelles are divided on the bases of their membrane;
 Double membrane organelles
1. Mitochondria 2. Plastid 3. Vacuoles
 Single membrane organelles
1.Lysosomes 2. Micro bodies
 Non-membranous organelles
1. Ribosome
 End membranous organelles
1. Endoplasmic reticulum 2. Golgi bodies
 Micro tubular organelles
1. Centriole 2. Cilia and flagella
 Nucleus
1. Nucleolus

5. PLASMA MEMBRANE
DEFINATION
“In all types of cells weather it is plant, animal or naked a very thin, semi
permeable membrane is present around the cells which are
responsible for entry and exit of all types of ions and molecules
called as plasma membrane.”
UNIT MEMBRANE CONCEPT
 In 1935 Denielli and Davidson spoke about structure of plasma
membrane. According to them plasma membrane is the three
layered membrane and made up off protein and lipids.
 In 1960-62 Robertson supported this theory and give the unit
membrane concept for plasma membrane. According to him;
 “Plasma membrane and the other entire membrane which are
present in cell are made up off unit membrane. Even endoplasmic
reticulum, Golgi bodies, ribosome, lysosomes, nucleus are also
made up off unit membrane.”

6. STRUCTURE OF PLASMA
MEMBRANE
Denielli and Davidson (1935) first saw the electron
microscopic structure of the plasma membrane
according to them;
 The external dense layer of plasma membrane is
made up off protein and the thickness of this layer is
20Angustrom.
 The middle light layer is made up off phospholipids
and the thickness of this layer is 35Angustrom.
 The internal dense layer is made up off protein and
the thickness of this layer is also 20Angustrom.
 The total thickness of the membrane is 75Angustrom.

7. FIG: Structure of plasma membrane

8. MOLECULE STRUCTURE
The fact that the plasma, membrane is made
up off two chemical molecules, protein and
lipids are conformed. But the lipids which are
present in plasma membrane is of the two
types on the basis of their ends;
 Hydrophobic end: This end is insoluble in water and
made up off fatty acid that’s why this ends are called
non-polar ends.
 Hydrophilic end: This ands are made up off glycerol
and they are soluble in water and this ends are called
polar ends.

9. DIFFERENT THEORYS FOR
PLASMA MEMBRANE
 LAMELAR THEORY: This theory is proposed by Denielli and Davidson, according to
them plasma membrane is a bi-molecular membrane which is composed with the two
layers of protein and one layer of phospholipids. The molecules of the phospholipids
are arranged on the bases of their polar and non-polar ends.
 FLUID MOSAIC MODEL THOERY: This theory is proposed by Singer and Nicolson
in 1970, according to them;
“At the middle of the plasma membrane there are double
layer of lipid molecules is present and the polar end of the
lipid molecules is present outer side but the non polar end is
present inner side because of this arrangement of lipid molecules
water molecules can not enter to the membrane but this molecules
are permeable for the fat soluble molecules.”
Singer and Nicolson also notes that the proteins which is present in
lipid layer are of two types:
 Integral protein: Some proteins are placed into the lipid layer and they look like
a mosaic this are called integral protein.
 Peripheral protein: These types of proteins are present on the outer part of lipid
layer this are called peripheral protein.

11. CHEMICAL COMPOSITION
Now we know that the plasma membrane is
made up off lipids and proteins but
carbohydrates are also present in plasma
membrane in the form of glycolipid’s and
glycoprotein's.
So the chemical composition of the plasma
membrane is:
 Proteins – 60-80%
 Lipids – 20-40%
 Carbohydrates – 5%

12. PROTOPLASM and
CYTOPLASM
Protoplasm is the living content of a cell that is
surrounded by a plasma membrane. This term is not
commonly used in modern cell biology. Protoplasm is
composed of a mixture of small molecules such as
ions, amino acids, monosaccharide and water, and
macromolecules such as nucleic acids, proteins,
lipids and polysaccharides. In eukaryotes the
protoplasm surrounding the cell nucleus is known as
the cytoplasm and that inside the nucleus as the
nucleoplasm. In prokaryotes the material inside the
plasma membrane is the bacterial cytoplasm, while
In gram negative bacteria the region outside the
plasma membrane but inside the outer membrane is
the periplasm.

13. FUNCTION
 Plasma membrane made the outer protective
layer for the cell and cell organelles.
 They show the semi permeability for the cells.
 They took part in cell transportation.
 They give the mechanical support to the cell.
 They help cell for motion and flexibility.

14. CELL WALL
DEFINATION
“A cell wall is a tough, usually flexible but
some times fairly rigid layer that surrounded
some of cells. It is located outside the cell
membrane and provides these cells with
structural support and protection and also
act as a filtering mechanism. They are found
in plants, bacteria, fungi and some animals
and protozoa do not have cell wall.”

15. STRUCTURE
Cell wall consists of 3 types of layers:
 Middle lamella: This is the first layer formed during
cell division. It makes up the outer wall of the cell and
is shared by adjacent cells. It is composed of pectic
compounds and protein.
 Primary wall: This is formed after the middle lamella
and consists of a rigid skeleton of cellulose micro
fibrils embedded in a gel-like matrix composed of
pectic compounds, hemicellulose, and glycoprotein's.
 Secondary wall: formed after cell enlargement is
completed. The secondary wall is extremely rigid and
provides compression strength. It is made of
cellulose, hemicellulose and lignin. The secondary
wall is often layered.

16. FIG: STRUCTURE OF CELL WALL

17. CHEMICAL COMPOSITION
Cell wall is made up off polysaccharide
cellulose. Another component apart from
cellulose like hemi cellulose and different
types of polysaccharide are also found in cell
wall. The main component of middle lamella
is calcium and magnesium pacted. Primary
and secondary wall mainly contain cellulose.
Lignin, suberine, gum, tannin and minerals
Like silica, calcium oxalate and calcium
carbonate are also found in cell wall.

18. FUNCTION
 Support and mechanical strength.
 Maintaining cell shape.
 Controlling turgor pressure.
 Protection of cell.
 Reserve of carbohydrates.

19. CELL COAT
Cell coat is a covering over the plasma
membrane of most animal cell. Animal cell
which not have cell wall covered with cell
coat. It consists of glycoprotein and
polysaccharides and has a chemical
composition that differs from comparable
structure in either plants or bacteria. The
cell coat provides a biochemical identity at
the surface of the cell and these forms of
cellular identity are under control.

20. MITOCHONDRIA
HISTORY
 In 1880 Sir kolliker found mitochondria in insect cell.
 In 1882 Flemming saw a filamentous structure of mitochondria
in many cells.
 In 1912 Ringsbury co-relate mitochondria to respiration.
DEFINATION
“In cell biology, a mitochondrion (plural mitochondria)
is a membrane-enclosed organelle found in most eukaryotic
cells .These organelles range from 0.5 to 10 micrometers
(μm) in diameter. Mitochondria are sometimes described as
"cellular power plants" because they generate most of the
cell's supply of adenosine triphosphate (ATP), used as a
source of chemical energy. In addition to supplying cellular
energy, mitochondria are involved in a range of other
processes, such as signaling, cellular differentiation, cell
death, as well as the control of the cell cycle and cell
growth.”

21. STRUCTURE
A mitochondrion contains outer and inner membranes
composed of bilayer and proteins. The two membranes,
however, have different properties. Because of this double
membraned organization, there are five distinct
compartments within the mitochondrion. There is the outer
mitochondrial membrane, the intermembrane space (the
space between the outer and inner membranes), the inner
mitochondrial membrane, the crista space (formed by
infoldings of the inner membrane), and the matrix (space
within the inner membrane).
 OUTER MEMBRANE: The outer mitochondrial membrane, which
encloses the entire organelle, it contain large number of integral protein
called porins.
 INTERMEMBRANE SPACE: The intermembrane space is the space
between the outer membrane and the inner membrane.
 INNER MEMBRANE: The inner mitochondrial membrane contains
proteins with many types of functions.

22.  CRISTAE: The inner mitochondrial
membrane is compartmentalized into
numerous cristae, which expand the surface
area of the inner mitochondrial membrane,
enhancing its ability to produce ATP. For
typical liver mitochondria the area of the inner
membrane is about five times greater than
the outer membrane. This ratio is variable
and mitochondria from cells that have a
greater demand for ATP, such as muscle
cells, contain even more cristae. These folds
are studded with small round bodies known
as F1 particles or oxysomes.

23.  THE MATRIX: The matrix is the space
enclosed by the inner membrane. It
contains about 2/3 of the total protein in
a mitochondrion. The matrix is important
in the production of ATP with the aid of
the ATP synthase contained in the inner
membrane. The matrix contains a
highly-concentrated mixture of hundreds
of enzymes, special mitochondrial
ribosome, tRNA, and several copies of
the mitochondrial DNA genome.

24. FIG: STRUCTURE OF MITOCHONDRIA

25. FUNCTION
 The most prominent roles of
mitochondria are to produce ATP through
respiration.
 They regulate cellular metabolism.
 They also took part in protein synthesis.
 They produce egg yolk and middle part of
spam.

26. PLASTID
DEFINATION
“Plastids are major organelles found in
the cells of plants and algae. Plastids
are the site of manufacture and
storage of important chemical
compounds used by the cell. Plastids
often contain pigments used in
photosynthesis, and the types of
pigments present can change or determine
the cell's colour.”

27. TYPES OF PLASTID
 LEUCOPLAST: are colorless plastids and occur in
plant cells not exposed to light, such as roots and
seeds. They are colorless due the absent of
pigments.
 CHROMOPLAST: are red, yellow or orange in colour
and are found in petals of flowers and in fruit. Their
colour is due to two pigments, carotene and
xanthophyll.
 CHLOROPLAST: are probably the most important
among the plastids since they are directly involved in
photosynthesis. They are usually situated near the
surface of the cell and occur in those parts that
receive sufficient light, e.g. the palisade cells of
leaves. The green colour of chloroplasts is caused by
the green pigment chlorophyll.

28. CHLOROPLAST
DEFINATION
“Chloroplasts are organelles found in
plant cells and other eukaryotic
organisms that conduct
photosynthesis. Chloroplasts capture
light energy to conserve free energy in
the form of ATP and reduce NADP to
NADPH through a complex set of
processes called photosynthesis.”

29. STRUCTURE
Chloroplasts are observable as flat discs usually 2 to 10
micrometers in diameter and 1 micrometer thick. In land plants,
they are, in general, 5 μm in diameter and 2.3 μm thick. The
chloroplast is contained by an envelope that consists of an inner
and an outer phospholipid membrane. Between these two layers is
the intermembrane space. A typical parenchyma cell contains
about 10 to 100 chloroplasts. The material within the chloroplast is
called the stroma, corresponding to the cytosol of the original
bacterium, and contains one or more molecules of small circular
DNA. It also contains ribosomes; however most of its proteins are
encoded by genes contained in the host cell nucleus, with the
protein products transported to the chloroplast. Within the stroma
are stacks of thylakoids, the sub-organelles, which are the site of
photosynthesis. The thylakoids are arranged in stacks called grana
(singular: granum). A thylakoid has a flattened disk shape. Inside it
is an empty area called the thylakoid space or
Lumen, Photosynthesis takes place on the thylakoid membrane.

31. CHEMICAL COMPOSITION
 Protein – 35-55%
 Lipid – 20-30%
 Carbohydrates – 4-7%
 Pigments – 9-13%
Chloroplast consist 2 types of pigments:
 chlorophyll
 carotenoid
 Chlorophyll
“Chlorophyll is a green pigment found in all plants,
algae and cyanobacteria. Chlorophyll absorbs light
most strongly in the blue portion of the
electromagnetic spectrum, followed by the red
portion.”
Two types of chlorophyll mostly found in plant cells
are:
 chlorophyll a
 chlorophyll b

32. FUNCTION
 Chloroplast during the photosynthesis
produces food material and oxygen for the
plant.
 Chlorophyll provides the enzymes which are
needed to complete the synthesis of fatty acids
and crab’s cycle.
 Chromoplast gives different colors to the
plants.
 Respectively Leucoplast stores the food
material for plants.

33. ENDOPLASMIC
RETICULUM
DEFINATION
“The endoplasmic reticulum (ER)
is an eukaryotic organelle that
forms an interconnected network
of tubules, vesicles, and
cisternae within cells.”

34. STRUCTURE
The general structure of endoplasmic
reticulum is an extensive membrane network
of vacuoles. These vacuoles are nothing but
the unit membrane made.
Vacuoles are found in cytoplasm in the form of:
 CISTERNAE: These are the filamentous, flat and
alternative arranged vacuoles. These vacuoles are
found in photosynthetic cells.
 VESICLES: These are the round shape vacuoles
witch are found in protein synthetic cells.
 TUBULES: These vacuoles are in the form of
tubules and found in non -secretary cells like retina
and muscle cells.

35. FIG: Structure of endoplasmic reticulum

36. FUNCTION
 Mechanical support to cell.
 Transport of protein.
 Transport of genetic material.
 Formation of cell plate.
 Helps in glycosylation.

37. GOLGI BODIE
DEFINATION
“Also known as the Golgi body or Golgi
complex, a collection of vesicles and
folded membranes in a cell, usually
connected to the endoplasmic reticulum
(ER). It stores and later transports the
proteins manufactured in the endoplasmic
reticulum.” It is named after the Italian
histologist Camilio Golgi(1898).

38. STRUCTURE
 The Golgi is composed of stacks of membrane-bound structures known
as cisternae (singular: cisterna). An individual stack is sometimes
called a dictyosome, especially in plant cells. A mammalian cell
typically contains 40 to 100 stacks. Between four and eight cisternae
are usually present in a stack; however, in some protists as many as
sixty have been observed. Each cisterna comprises a flattened
membrane disk, and carries Golgi enzymes to help or to modify cargo
proteins that travel through them. They are found in both plant and
animal cells.
 The cisternae stack has four functional regions: the cis-Golgi network,
medial-Golgi, endo - Golgi, and trans-Golgi network. Vesicles from the
endoplasmic reticulum (via the vesicular-tubular clusters) fuse with the
network and subsequently progress through the stack to the trans Golgi
network, where they are packaged and sent to the required destination.
Each region contains different enzymes which selectively modify the
contents depending on where they reside. The cisternae also carry
structural proteins important for their maintenance as flattened
membranes which stack upon each other.
 The trans face of the trans-Golgi network is the face from which
vesicles leave the Golgi. These vesicles then proceed to later
compartments such as the cell membrane, secretory vesicles or late
endosomes.

39. FIG: STRUCTURE OF GOGI BODIE

40. FUNCTION
 They made secretory vesicles which are
bust near the plasma membrane and
release the protein outer the cell.
 Burgos and Fowcett (1955) found that
they made the acrosomes of spames.
 Transport of protein.
 Formation of lysosomes.
 Synthesis of carbohydrates.

41. RIBOSOME
“Ribosome’s are the components of cells that
make proteins from amino acids. One of the
central tenets of biology, often referred to as the
"central dogma," is that DNA is used to make
RNA, which, in turn, is used to make protein. The
DNA sequence in genes is copied into a
messenger RNA (mRNA). Ribosomes then read
the information in this RNA and use it to create
proteins. This process is known as translation
(genetics), i.e. the ribosome "translates" the
genetic information from RNA into proteins.”

43. STRUCTURE
A ribosome is not just one piece. There are two pieces or
subunits. Scientists named them 60-S (large) and 40-S
(small). When the cell needs to make protein, mRNA is
created in the nucleus. The mRNA is then sent into the
cell and the ribosomes. When it is time to make the
protein, the two subunits come together and combine with
the mRNA. The subunits lock onto the mRNA and start
the protein synthesis.
The 60-S/ 40-S model works fine for eukaryotic cells.
Prokaryotic cells have ribosomes made of 50-S and 30-S subunits.
It's a small difference, but one of many you will find in the two
different types of cells.

44. FUNCTION
The most important function of ribosome is
to produce proteins that are why ribosome
is called protein producing factory.

45. NUCLEUS
DEFINATION
“In cell biology, the nucleus also sometimes
referred to as the "control center", is a
membrane-enclosed organelle found in
eukaryotic cells. It contains most of the cell's
genetic material, organized as multiple long
linear DNA molecules in complex with a large
variety of proteins, such as histones, to form
chromosomes. The genes within these
chromosomes are the cell's nuclear genome.”

46. STRUCTURE
The structure of a cell nucleus consists of nuclear membrane
(nuclear envelope), nucleoplasm, nucleolus and chromosomes.
Nucleoplasm, also known as karyoplasm.
 NUCLEAR MEMBRANE: The nuclear membrane is a double-
layered structure that encloses the contents of the nucleus. The
outer layer of the nuclear membrane is connected to the
endoplasmic reticulum. A fluid-filled space or perinuclear space
is present between the two layers of a nuclear membrane. The
nucleus communicates with the remaining of the cell or
cytoplasm through several openings called nuclear pores.
Nuclear pores are the sites for the exchange of large molecules
(proteins and RNA) between the nucleus and cytoplasm.
 NUCLEOPLASM: The nucleoplasm is one of the types of
protoplasm, and it is enveloped by the nuclear membrane or
nuclear envelope. The nucleoplasm is a highly viscous liquid
that surrounds the chromosomes and nucleoli.

47.  CHROMOSOME: Chromatin is the combination of DNA and
proteins that makes up chromosomes. It is found inside the
nuclei of eukaryotic cells. The major components of chromatin
are DNA and histone proteins, although other proteins have
prominent roles too. The functions of chromatin are to package
DNA into a smaller volume to fit in the cell, to strengthen the
DNA to allow mitosis and meiosis, and to serve as a mechanism
to control expression and DNA replication. Chromatin contains
genetic material-instructions to direct cell functions. Changes in
chromatin structure are affected by chemical modifications of
histone proteins such as methylation (of DNA and proteins) and
acetylation (of proteins), and by non-histone, DNA-binding
proteins. It is divided between:
 Heterochromatin (condensed )
 Euchromatine ( extended )
 NUCLEOLUS: The nucleolus (also called nucleole) is a non-
membrane bound structure composed of proteins and nucleic
acids found within the nucleus. The first step in ribosomal
assembly is transcription of the rDNA, by a protein called RNA
polymerase I, forming a large pre- rRNA precursor. This is
cleaved into the subunits 5.8S, 18S, and 28S rRNA. The
transcription, post-transcriptional processing, and assembly of
rRNA occurs in the nucleolus

49. CONCLUSION
REFERENCE
 Karp, “ cell and molecular biology”
 Lynsey Peterson, “mastering the parts of cell”
 www.biology4kids.com/files/cell_main
 www.cellularbiology.com