Cytoplasm and Cell Organelles: Study Notes

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CYTOPLASM:

The protoplasm of the cell outside the nucleus is called cytoplasm.

1. The cytoplasm is a semi-fluid colloid that fills the cell.
2. It exhibits active streaming movements around the inner surface of the cell called cyclosis.
3. It has 2 distinct parts:

• The outer portion is called ectoplasm and it appears clear.
• The inner portion is called endoplasm and it appears granular.

1. Cytoplasm contains several types of organelles, embedded in a fluid matrix called the cytosol containing salts, sugar, amino acids, proteins, fatty acids, nucleotides and other substances.
2. The cytoplasm maintains shape with the help of a network of proteins fibers called cytoskeleton, which is also connected to many organelles. It also helps the cells in movement.
3. The cell organelles can be grouped on the basis of presence or absence of a membrane.

Cytoplasmic Organelles:

• Membrane-Bounded Organelles: Endoplasmic Reticulum, Golgi Apparatus, Plastids, Glyoxysomes, Mitochondria, Lysosomes, Peroxisomes, Vacuoles
• Non-Membrane-Bounded Organelles: Centrosomes, Cytoskeleton, Ribosomes

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