Mitochondria By Amy and
Gabrielle
Structure
- 1) largest organelles in the cytoplasm.
- 2) diameter between .5 and 1 micrometer.
- 3) tubular and shaped like a kidney.
- 4) found in Eukaryote cells, not in bacteria.
- 5) contain two membranes:
- ( outer membrane has a smooth exterior.
- ( inner membrane is folded into layers called
cristae.
- 6) cristae divides cell into two sections.
- ( a matrix that lies inside the inner membrane.
- ( outer compartment that lies between two
membranes
- 7) matrix contains enzymes that break down carbohydrates
and in effect, carry out cellular respiration.
- 8) average of 3,000 to 5,000 mitochondria in the human
cell.
- 9) contain their own DNA.
Evolution and Reproduction
- 1) Endosymbiosis Theory
- ( supports the belief that mitochondrion and
chloroplasts are predecessors of Eukaryotes.
- ( originated from Prokaryote cells because they
are the same size as bacteria and some contain cristae
folds similar to those of the mitochondria.
- ( discovered in 1880
- 2)Reproduction of Eukaryote cells
- ( mitochondria divide into two when the Eukaryote
cells split during the process of meiosis and mitosis.
- ( mitochondria can not be grown in a cell free
culture.
Functions
- 1) make energy from the food we eat.
- ( breaks down carbohydrates and sugars into ATP
- (adenosine triphosphate) in a biochemical
reaction called cellular respiration.
- 2) cellular respiration uses oxygen and involves two
main pathways.
- ( carbon pathway; where sugar is broken down into
carbon dioxide and hydrogen.
- ( hydrogen pathway; where hydrogen transfers into
oxygen which forms water and releases energy.
- ( released energy stored in molecules of ATP.
- 3) ATP
- ( stores cell's energy needed for protein
manufacture, DNA replication and consumption of new
organelles.
- (needed for muscle contraction, pumping water
through membranes, and cell movement.
- 4) control the concentration of water, calcium, and ions
in cytoplasm. They also breakdown and recycle the
energy contained in fatty and amino acids.
Mitochondrial Diseases
- 1) When mutations occur in the mitochondria, ATP supply
decreases and therefore the energy of the cell also
decreases.
- ( as more mutations occur throughout the body,
whole systems fail and the person dies.
- ( the brain, heart, and skeletal muscles are the
most vulnerable because they require the most energy.
- ( one out of 10,000 people are affected by a
mitochondrial disorder.
- 2) symptoms:
- ( poor growth
- ( loss of motor control
- ( muscle weakness
- ( visual and/or hearing problems
- ( cardiac disease
- ( gastric-intestinal disorders
- ( respiratory disorders
- ( diabetes
- ( liver disease
- ( susceptibility to infection
- ( learning disabilities or retardation
- ( neurological problems and seizures
- 3) treatments:
- ( are not widely available
- ( can include vitamin and enzyme therapies and
physical and occupational therapy
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