The document describes the key components and structures of animal cells. It discusses the constituents of cells, including water, ions, proteins, lipids and carbohydrates. It then describes the main organelles found in animal cells, including the nucleus, cytoplasm, cell membrane, mitochondria, endoplasmic reticulum, Golgi bodies, lysosomes and peroxisomes. It explains the functions of these organelles and how they work together to keep the cell alive.
1. Discovery of cell In 1665 by Robert
HOOK
Constituents of cell
• Water – 70 -80%
• Ions - sodium, potassium,
phosphates
• Protein - 10-20%
• Lipid - 2 %
• Carbohydrates -1%
2. Definition of Cell
• A cell is the smallest unit that is
capable of performing life functions.
• Structural & Functional unit of life
• Typical cell consist of 3 fundamental
structures
Nucleus
Cytoplasm
Cell membrane
6. Nucleus
• Largest and most important cell
organelle
• Directs cell activities
• Contains genetic material – DNA
• It occupies 10% of total cell volume
• It is present in all cells except RBC
• Administrative center of cell
• Most of the cells are uninucleated
skeletal muscle cells multinucleated
8. Nuclear Membrane
• Surrounds nucleus
Separated from cytoplasm
• Made of two layers
• Outer layer continuous
with endoplasmic reticulum
• Nuclear pore-inner layer
has nuclear pores with 90
nm diameters
• Openings allow material to
enter and leave nucleus
9. Nucleolus
• Inside nucleus
• Prominent ,dense
mass, store house of
mRNA
• Involved in synthesis
of protein, ribosome
10. • Gel like fluid portion contain many
enzymes like RNA polymerase ,DNA
polymerase, amino acid & lipid
metabolism
• Involved in vital metabolic reactions
• Contain genetic material in the form
of DNA
Nucleoplasm
11. Chromosomes
• Made of DNA
• Contain instructions for
traits & characteristics
• Long DNA molecule
complexed with protein
to form chromatin &
further organised to
chromosomes
12. Functions
• It stores hereditary material DNA
• Control & co-ordinate activities of
cell organelle
• Responsible for growth, maturation &
reproduction
• control center of protein synthesis
13. Cytoplasm
semiliquid gel like mass
containing variety of
organelle
Occupying 55% of total
cell volume
Functions –
enz.regulation of
intermediately metabolism
storage of fat, CHO,
secretary vesicles
Responsible for size,
14. It is 2nd largest cell
organelle
Respiratory center of
cell
It is power house of cell
Spherical ,rod, oval
shaped
It contain their own
DNA
1.Mitochondria
15. Mitochondrial membrane
• Bounded by two membranes
• Outer is smooth & permeable to the most
of substances
• Inner is folded to form cristae it has
selective permeability it increases surface
area
• Internal chamber contain matrix
• ETC & component of oxidative
phosphorylation present on inner
16. • Matrix contain imp enzymes require
for the
1. energy metabolism of
CHO,lipid,amino acids like citric acid
cycle β-oxidation
2. urea & heme synthesis
• Also contain circular double stranded
DNA,RNA, ribosomes
17. 1. Involved in cellular metabolism
2. Energy production by oxidation of
foodstuff
3. TCA,B –oxidn ,urea synthesis, ketone
bodies production takes-place
4. Generation of reducing equivalent
5. principle producer of energy
6. Site of ETC & oxidative phosphorylation
Functions of mitochondria
18. 2.Endoplasmic Reticulum
• Network of interconnecting
flattened membrane bound
vesicles & tubules
•continuous from perinuclear
envelope to cell membrane
also connected with Golgi
•It is a site of protein & lipid
syn
19.
20. Two types
Smooth type :
-lacks ribosomes giving smooth
appearance
-involve in synthesis of TG,PL,sterols
Rough type :
-coated with ribosome's
–involve in protein synthesis
– granular appearance
21.
22. • RER – protein synthesis , SER – synthesis of
lipid, steroid hormone,cholestrol,TG
•Involved in modification & transport of protein
• Detoxification - involved in drug metabolism
•Neutralization of hormones & toxic substances
•Transport, modification, secretion of
Glycoprotein & lipoproteins
•Storage of calcium in muscles released during
contraction - relaxation
Functions
23. Golgi Bodies
• Protein 'packaging
plant'
• Closely associate
with ER
• Unique cluster of
membrane vesicle
• Network of
flattened smooth
membranous vesicles
24. Functions
• Involved in the membrane synthesis
particularly for formation of
peroxisomes, lysosomes
• Site of post-translational modifications
• modification of newly synthesized protein
& exportation
• Site of protein sorting, packaging,&
secretion-glycosylation of protein
25. Lysosome
• Digestive 'plant' for
proteins, fats, and
carbohydrates
• Collectively called as
suicidal bag
• Spherical vesicle with
single membrane
• Transports undigested
material to cell
membrane for removal
26. pH of lysosomal matrix is acidic < 5 so
imp. in degradation & recycling
• It contain degradative enzymes like
Lipases (lipid)
Glucosidase (glycogen)
Ribonucleases ( RNA)
Cathapsins ( protein)
27. Functions
• Degradation of unwanted substances
inside cell
• Degradation of external harmful bacteria
• Function is varies according to its locality
• Kills & remove ineffective organisms &
foreign bodies
• Autolysis –
• Remove intracellular product of
metabolism from cell
28. Deficiency of lysosomal enzymes causes
diseases like glycogen/fat storage
disease
Example –
pompe’s disease
tay-sachs disease
29. Peroxisomes
•These are small organelle called microbodies
•Single membrane cellular organelle
•Spherical or oval in shape approx. 0.5 µ in
diameter
•Synthesized from budding of smooth ER
•It contain enzymes like catalase,peroxidase
•Largely present in the hepatic & renal cells
•It separates their content from cytosol
30. Functions
• Get rid of toxic substances from cell
• Catalase protects the cell from toxic
effects of H2O2
• Peroxisomes are involved in oxidation
of long chain fatty acids
• Involved in synthesis of plasmalogens
and glycolipid
• Regulate NAD/NADH ratio in cell
31. Nucleus – Managers office
Mitochondria – Power generating plant
Golgi – Post office
ER – Production unit
Lysosomes – Suicidal bags
Vacuoles – Lorries carrying waste
33. • All cells have a cell membrane
• Highly viscous, plastic structure
• Functions:
1. Controls what enters and exits
the cell to maintain an internal
balance called homeostasis
2.Provides protection and
support for the cell
picture of a real cell
membrane.
34. 4. Act as barrier between ICF & ECF
5.Selective permeability
6.Conduct action potential
7.Nutrients absorbed metabolic waste
excreted outside
8.Maintainance of size, shape, skeleton
9.Act as a receptor for various chemical
messages
36. Chemical composition - Lipid
Three major lipids
A)Glycerophospolipid / phospholipid
B)Glycosphingolipid
C)Sterols
It is composed of a lipid bilayer.
The most common molecule in the model is the phospho
Cholesterol fills up the gap at certain places
37. Lipid Bilayer -2 layers of
phospholipids
a.Phosphate head is polar
(water loving)
b.Fatty acid tails non-polar
(water fearing)
c.Proteins embedded in
membrane
Phospholipid
Polar heads
love water
& dissolve.
Non-polar
tails hide
from water
38. Chemical composition - Proteins
Major functional molecule of membrane
Consist of enzymes, pumps, channels, receptors,
antigens
Two types
Integral membrane protein
interact extensively with phospholipid
assymetrically arranged
Peripheral proteins
not interact with Phospholipid
Loosly attached to the surface
39. Complex carbohydrates are attached to protein or
lipid molecules.
polysaccharide region face outward on cellular
membrane.
Have highly branched, 3-D shapes; > 35,000
variations are found
Functions
Act as receptor sites to identify foreign substances
Bind to hormones, neurotransmitters & other
incoming chemical signal
Carbohydrates
40. Outside of cell
Inside of cell
(cytoplasm)
Lipid
Bilayer
Transport
Protein Phospholipids
Proteins
Carbohydrate
chains
Structure of the Cell Membrane
Go to
Section:
41. Fluid Mosaic Model
fluid or flexible
lipid & protein molecules
are free to move
within membrane.
molecules or large sections of membrane can easily be
added or removed molecules
mosaic – design made of inlaid work
different types of proteins built into lipid
bilayer gives the appearance.
