Eukaryotic Cell Structure and Organization
The eukaryotic cell contains various membrane-bound organelles that perform specialized functions. The nucleus, the largest organelle, features a porous membrane allowing controlled substance exchange and contains nucleoplasm with DNA. The endoplasmic reticulum system consists of folded membrane channels forming cisternae for material synthesis and transport.
Definition: Eukaryotic cells are characterized by membrane-bound organelles, distinguishing them from prokaryotic cells.
Highlight: The rough endoplasmic reticulum is specifically equipped with ribosomes for protein synthesis and packaging.
Vocabulary: Cisternae - flattened membrane disks within the endoplasmic reticulum.
Example: The Golgi body processes proteins through a series of flattened membrane vesicles, preparing them for transport to the cell surface.
Quote: "Containing 'cocktail' of hydrolytic enzymes" - referring to lysosomes' role in breaking down cellular materials.
The mitochondrion features a distinctive double-membrane structure with inner foldings called cristae, housing the matrix where ATP production occurs through aerobic respiration. Ribosomes, either free-floating or attached to the ER, serve as sites for polypeptide synthesis. Centrioles, positioned near the nucleus, participate in spindle fiber formation during cell division. Lysosomes, single-membrane structures formed from rough ER, contain enzymes for breaking down cellular waste and toxins for material recycling.