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The Cell
The cells and organelles
The structure of cell
• Organisational levels of cell
• Criterias of a living cell
• Classification of cells on the
basis of no. & nuclear
membrane sizes of cells
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Plasma membrane
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Kinds of permeability
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Impermeaility
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Permeability
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Semipermeability
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Selectively permeability-
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Fluid mosaic model of P.M.
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Movement of substances
across membrane
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diffusion
Osmosis
Click here to view animation
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Hypotonic ,isotonic & hypertonic solutions
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Endosmosis & exosmosis
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Special processes involved in
transport of materials
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Endocytosis & exocytosis
Endosymbiosis
Click here to view animation
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Functions of nucleus-central role in cellular
reproduction
Controls all metabolic activities
Every eukaryotic cell has fixed no.of
chromosomes
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The paired condition of chromosomes is diploid
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Diploid cell-full no. Of chromosomes
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Unpaired chromosomes of each kind is a
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Haploid cell ,has half no. Of chromosomes
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Cell wall
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Location-plant cells,bacteria,fungi
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Structure-primary cell wall is made up of cellulose
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Cellulose is insoluble fibrous polysacccharide
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Primary cell wall-mechanical strength&protection
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Secondary cell wall-inner face of the primary wall
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Composed of liginin,suberin substances
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Plant cell -living -only primary cell wall
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Plant cell-non-living secondary cell wall is
deposited on the inner
Face of primary cell wall
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Nucleus
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Location-plant cell -pushed on one side of cell
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Animal cell-centrally located uninucleated,
binucleated, multinucleated
Resting nucleus -spherical
Chemically nucleus80%protein,12%DNA,5%RNA, 3%lipids
Structure of nucleus under microscope
Cytoplasm

The cytoplasm is the part of a cell that
is enclosed within the cell membrane.
Plastid
The effect of the pds3 mutation on plastid development. (A) wild-type. (B)
Plastids in leaf mesophyll cells of purple seedlings 5 days after germination.
(C) Plastids in leaf mesophyll cells of albino seedlings 30 days after
germination. (D) Plastids in leaf mesophyll cells of albino seedlings 90 days
after germination. St: starch granule; Tk: thylakoid; Oil: oil drops; PG:
plastoglobule. Scale bar = 1.2 m.
Chloroplast
Chromoplast
Prokaryotic cell & eukaryotic cell
The prokaryotes are a group of organisms that lack a
cell nucleus or any other membrane-bound organelles.
They differ from the eukaryotes, which have a cell
nucleus. Most are unicellular.
endoplasmic reticulum
The endoplasmic reticulum (ER) is an eukaryotic
organelle that forms an interconnected network of
tubules, vesicles, and cistern within cells.
mitocondria
A mitochondrion is a membrane-enclosed organelle
found in most eukaryotic cells. 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.
lysosomes
Lysosomes are spherical organelles that contain
enzymes that break up endocytized materials and
cellular debris. They are found in animal cells
Insert from wikipedia
vacuoles
A vacuole is a membrane bound organelle
which is present in all plant and fungal cells and
some protist, animal and bacterial cells.
Ribosomes
Centrosome
Click here for pictures
some interesting facts about cells
1. The Longest Cell in your body is the motor neuron
cell, which is located in the spinal cord, near the
central nervous system.
2. It is believed that there are more nerve cells in your
brain than stars in the milky way.