Organelles With DNA

Mitochondria
 bounded
by exterior and interior membranes
 interior partitioned by cristae

Chloroplasts
 have
enclosed internal compartments of stacked grana,
containing thylakoids
 found in photosynthetic organisms
Mitochondria
A. "Powerhouse of the cell" - cellular metabolism
B. Structure- outer and inner membranes, cristae
C. Have their own DNA
Mitochondria- Introduction
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sausage-shaped typically 1 to
4μ long, divide by fission
outer membrane is porous
less porous inner membranes
loosely described as a large
wrinkled bag packed inside
of a smaller, unwrinkled bag.
http://www.tutorvista.com/biology/structure-mitochondria
Outer membrane
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simple phospholipid bilayer, containing protein structures
called porins
Porins render it permeable to molecules of about 10
kilodaltons or less (the size of the smallest proteins).
Ions, nutrient molecules, ATP, ADP, etc. can pass through the
outer membrane with ease.
The intermembrane space has an important role in the
primary function of mitochondria, which is oxidative
phosphorylation.
Inner membrane
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freely permeable only to oxygen, carbon dioxide, and
water.
Its structure is highly complex, including all of the
complexes of the electron transport system, the ATP
synthetase complex, and transport proteins.
The wrinkles, or folds, are organized into lamillae
(layers), called the cristae (singlular: crista).
The cristae greatly increase the total surface area of
the inner membrane.
Matrix
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contains the enzymes for the citric acid cycle reactions.
The matrix also contains dissolved oxygen, water, carbon
dioxide, the recyclable intermediates that serve as energy
shuttles,
matrix components can diffuse to inner membrane
complexes and transport proteins within a relatively short
time-diffusion is slow process.
Isolated mitochondria, show a rounded appearance in
electron micrographs-mitochondria are spherical
Plastids three types
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1. Chloroplast: By trapping solar energy, green plastids
manufacture food through photosynthesis
2. Chromoplasts provide color to various flowering
parts
the primary function in the cells of flowers is to attract agents
of pollination, and

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in fruit to attract agents of dispersal
3.Leucoplasts are the centers of starch grain formation;
they are also involved in the synthesis of oils and proteins
Chloroplasts
•Chloroplasts are larger and
more complex than mitochondria
•Grana – closed compartments
of stacked membranes
•Thylakoids – disc shaped
structure – light capturing
pigment
•Stroma – fluid matrix
three membranes divide chloroplasts into three
distinct internal
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(1) the intermembrane space between the two
membranes of the chloroplast envelope;
(2) the stroma, which lies inside the envelope but
outside the thylakoid membrane; and
(3) the thylakoid lumen.
Endosymbiosis
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Endosymbiotic theory suggests engulfed
prokaryotes provided hosts with advantages
associated with specialized metabolic activities.
Theory of Endosymbiosis