Which one of the following cellular parts is correctly described?
Which one of the following cellular parts is correctly described?
Thylakoids-Flattened membranous sacs forming the grana of chloroplasts
Centrioles-Sites for active RNA synthesis
Ribosomes-Those on chloroplasts are larger $(80 \mathrm{~S})$ while those in the cytoplasm are smaller (70 S)
Lysosomes-Optimally active at a pH of about 8.5
Solution
The correct description of a cellular part is thylakoids, which are flattened membranous sacs that form the grana of chloroplasts. Centrioles are a membranous hollow microcylinders occur in pair and play important role in cell division.
Ribosomes in chloroplast are $70 \mathrm{~S}$ type while those of cytoplasm in eukaryotic cells are $80 \mathrm{~S}$ type. The enzymes of lysosome (called suicidal bag) function at acidic $\mathrm{pH}$ (i.e., 5).