Lysosomes, Mitochondria Flashcards
Lysosomes are…
spherical sacs, surrounded by a single membrane and having no internal structures.
Lysosomes diameter
0.1-0.5 micrometres
Lysosomes contain…
digestive(hydrolytic) enzymes, which must be kept separated from the other organelles.
Lysosomes are responsible for…
the breakdown of unwanted structures such as old organelles.
In white blood cells, lysosomes are…
used to digest bacteria.
Enzymes are sometimes released…
outside the cell. E.g. in the replacement of cartilage with bone during development.
The heads of sperm contain special…
lysosome, the acrosome, for digesting the path.
Mitochondria diameter
1 micrometre
Mitochondria can be…
various shapes, often sausage-shaped.
Mitochondria are surrounded by…
double membrane(envelope).
Cristae
The inner membrane is folded to form finger-like cristae which project the interior solution called the matrix.
Intermembrane
The space between the two membranes.
The outer membrane of mitochondria contains…
transport protein called porin, which forms wide aqueous channels allowing easy access of small, water-soluble molecules from the cytoplasm to enter the intermembrane space.
The inner membrane is far more…
selective barrier. It precisely controls which ions and molecules can enter the matrix.
Another function of mitochondria is…
the synthesis of lipids.
During respiration a series of…
reactions take place in which energy is released from energy-rich molecules. Most of this energy is transferred to molecules of ATP.
ATP
Adenosine triphosphate is the energy-carrying molecule found in all living cells. Known as the universal energy carrier.
The reactions of respiration take place in…
matrix and in the inner membrane (cristae). The matrix contains enzymes and these supply H and electrons to the reactions that take place in cristae.
The folding of cristae increases the…
the efficiency of respiration as it increases the surface area.
One made, ATP leaves…
the mitochondrion and as it is a small soluble molecule, it rapidly spread to all parts of the cell.
The energy is released by…
breaking down ATP to ADP(adenosine diphosphate). This is hydrolysis reaction. The ADP can be then recycled into mitochondrion for conversion back to ATP.
Cytoplasmic ribosomes are…
80S
Bacteria, mitochondria and ribosomes are…
70S
Endosymbiont theory
Mitochondria and chloroplast contain small circular DNA. It was proved that these organelles were ancient bacteria, which now live inside the larger cell.
