about mitochondria

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5. INTRODUCTION
Mitochondria are derived from bacteria by a process
termed as endosymbiosis.
Mitochondria arose about 2 billion years ago when a
bacterium fused with an archael cell or established a
symbiotic relationship with a primitive eukaryotic cell.
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6. Mitochondria is a double membrane bound organelle
found in cytoplasm of eukaryotic cells.
Mito – thread, chondrion – granule like.
First observed by Richard Altman ( 1894)
 Term mitochondria was coined by Carl Benda (1898)
They produce enzymes for the metabolic conversion
of food to energy
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7. MORPHOLOGY
 Size 0.05 – 1.0 µm in diameter.
Length 1 – 10 µm long
Shape Bean shaped , in fibroblast it is elongated and
thread like.
Number Depends on type, size and functional state of
cell.
Eg : an average liver cell contain around 1500
mitochondria.
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8. STRUCTURE
OUTER MEMBRANE
INTERMEMBRANE SPACE
INNER MEMBRANE
CRISTAE
MATRIX
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10. FUNCTION
Powerhouse of the cell
Mitochondria areresponsible for the conversion
of nutrientsinto energy–yielding molecule ATP
to fuelthe cells activities. The function known as
aerobic respiration is the reasonmitochondria
are frequently referred to asthe powerhouse of
the cell.
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11. OTHER FUNCTIONS
Production of heat( non shivering thermogenesis).
Role in apoptosis (programmed cell death).
Synthesis of estrogen and testosterone.
Role in neurotransmitter metabolism.
Role on cholesterol metabolism.
Role in heme synthesis.
Role in cellular proliferation.
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12. PLASTID
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13. INTRODUCTION
The plastid (Greek: plastós: formed, molded) is a
major organelle found in the cells of plants and algae.
Plastids are the site of manufacture and storage of
important chemical compounds used by the cell. They
often contain pigments used in photosynthesis, and
the types of pigments present can change or
determine the cell's colour. They possess a double
stranded DNA molecule, which is circular, like that of
prokaryotes.
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14. PLASTID IN PLANTS
 Those plastids which contain pigments can carry out
photosynthesis. Plastids can also store products like
starch and can synthesise fatty acids and terpenes,
which can be used for producing energy and as raw
material for the synthesis of other molecules. For
example, the components of the plant cuticle and its
epicuticular wax, are synthesized by the epidermal
cells from palmitic acid, which is synthesized in the
chloroplasts of the mesophyll tissue. All plastids are
derived from proplastids which are present in the
meristematic regions of the plant. 11

15.  Proplastids and young chloroplasts commonly divide
by binary fission, but more mature chloroplasts also
have this capacity. In plants, plastids may differentiate
into several forms, depending upon which function
they play in the cell.
 All plastids are derived from proplastids which are
present in the meristematic regions of the plant.
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16. STRUCTURE OF PLASTID IN PLANTS
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17. DEVELOPED FORMS OF PLASTID
Chloroplasts green plastids:
for photosynthesis; see also
etioplasts, the predecessors of
chloroplasts
Chromoplasts coloured
plastids: for pigment synthesis
and storage
Gerontoplasts: control the
dismantling of the
photosynthetic apparatus
during senescence
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18.  Leucoplasts colourless plastids: for monoterpene synthesis;
leucoplasts sometimes differentiate into more specialized
plastids:
Amyloplasts: for starch storage and detecting gravity
Elaioplasts: for storing fat
Proteinoplasts: for storing and modifying protein
Tannosomes: for synthesizing and producing tannins and
polyphenols
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19. REFERENCE
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