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Which one of the following cellular parts is correctly described?
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- Centrioles - Sites for active RNA synthesis.
- Lysosomes - Optimally active at a pH of about 8.5.
- Thylakoids - Flattened membranous sacs forming the grana of chloroplasts.
- Ribosomes - Those on chloroplasts are larger (80s) while those in the cytoplasm are smaller (70s).
Correct Option: C
Centrioles serve as basal bodies for cilia and flagella. They are concerned with spindle formation during cell division. Lysosomes are membrane-bound organelles containing many hydrolytic enzymes, which are optimally active at an acid pH (near pH 5). Thylakoids are membrane-bound organelles found within chloroplasts. The thylakoid membrane, forms many flattened, fluid-filled tubules that enclose a single convoluted compartment. These tubules tend to stack on top of each other to form a structure called a granum.
