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will u say more about lyososomes and mitochondria?

Lysosomes are membrane bound vesicles containing various hydrolytic enzymes necessary for digesting certain material in a cell. Lysosomes contain an ionic pump which maintains a highly acidic pH.

Lysosomes have 2 main roles:

    To digest macromolecules which enter the cell- They are like sacs which contain around forty digestive enzymes. The lysosomes infuse with vesicles of engulfed material and release the digestive enzymes to break up the material. The large molecules of food are broken down into smaller particles. The products diffuse through the lysosomes' membrane and are distributed throughout the rest of the cell. The products serve as building blocks of new materials.
    To breakdown old nonfunctioning organelle that out lived their usefulness- Cells fail to restore themselves causing them to age. Because of this lysosomes are needed to rid the cell of these unneeded materials that are occupying space in the cell. In stressed or dying cells' membrane, this component of the cell denigrates material, releasing the destructive lysosomal enzymes into the cytoplasm. Here they digest all organelles and speed up the cells' death by this process of autolysis (self-digestion). The products are recycled and reused to compose new parts of cells.

Lysosomes are formed by the Golgi apparatus. There are primary and secondary lysosomes. The primary are formed on the rough ER (endoplasmic reticulum). The secondary lysosomes are formed on the smooth ER by following the phagocytosis (process of taking solid materials into cells). Phagosomes fuse with lysosomes and work as one digestive vacuole. Lysosomal enzymes are released into this vacuole in order to digest the bacteria or other materials. Small molecules which are the result leave the vacuole through its membrane and are used to make new molecules. The indigestible materials are deposited outside the cell.

Mitochondria
Mitochondria are bounded by a double membrane. Each of these membranes is a phospholipid bilayer with embedded proteins. The outermost membrane is smooth while the inner membrane has many folds. These folds are called cristae. The folds enhance the "productivity" of cellular respiration by increasing the available surface area.

The double membranes divide the mitochondrion into two distinct parts: the intermembrane space and the mitochondrial matrix. The intermembrane space is the narrow part between the two membranes while the mitochondrial matrix is the part enclosed by the innermost membrane. Several of the steps in cellular respiration occur in the matrix due to its high concentration of enzymes.

Mitochondria are semi-autonomous in that they are only partially dependent on the cell to replicate and grow. They have their own DNA, ribosomes and can make their own proteins. Similar to bacteria, mitochondria have circular DNA and replicate by a reproductive process called fission.


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