What are the structural features for each of the following cell parts?Cell membrane, endoplasmic reticulum, chromosomes, golgi apparatus, mitochondria, chloroplasts, lysosomes, ribosomes, vacuole

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Cell membrane is a semi-permeable phospholipid bi-layer. The exposed heads of the layers are hydrophilic and the tails inside are hydrophobic.

Endoplasmic reticulum is a series of membranes (part of the cell's endomembrane system, which transfers protein). The outside of the membrane is covered with ribosomes, where the messenger RNA attaches, and the inside is called the lumen, where the RNA is translated into protein.

Chromosomes are single coils of DNA. Chromatin is the complex of DNA and protein of the chromosome. The two coiled chromosomes that make the 'X' are joined at the centromere. The DNA can be round or straight, long or short, depending on the cell.

Golgi Apparatus, the shipping yard, is a series of flattened membrane sacs which use chemical receptors and enzymes to repackage materials (i.e., polysacharrides, insulin) in vesicles before shipping them out to other parts of the cell.

Mitochondrion is a double membrane organelle that synthesizes ATP. The outside is smooth but the inside, called cristae, is so convoluted that it increases the surface area inside. This is where sugar and O2 make ATP.

Chloroplasts are found in cells that perform photosynthesis. They have two phospholipid membranes. Inside is an aqueous fluid called stroma. In the stroma are thykaloids (stacks of which are called grana). Stacks are linked by lamella; and inside each thykaloid is the lumen. Photosynthesis takes place on the thykaloid membrane.

Lysosome is a membrane-bound, spherical organelle containing hydrolytic enzymes: responsible for intracellular digestion. These often fuse with vacuoles in digestion.

Ribosomes are packets of RNA and protein, usually located on the endoplasmic reticulum or suspended in cytoplasm. They have two subunits which work together to translate mRNA into protein. Ribosomes have no membrane.

Vacuole is a membrane bound sac, similar to a lysosome, which is active in cell digestion and release of cellular waste products. In plant cells, it also patches cell wall/membranes and sustains cell rigidity by retaining water.

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