$A$ student wants to study cell structure using a light microscope with a $10 \times$ eyepiece and a $45 \times$ objective lens. Which of the following light sources should they use to obtain the best resolution?

Which of the following statements are incorrect?
$(i)$ Plant cells have centrioles which are absent in almost all animal cells.
$(ii)$ Ribosomes are the site of protein synthesis.
$(iii)$ The middle lamella is a layer mainly of calcium carbonate which holds the different neighbouring cells together.
$(iv)$ In animal cells, steroidal hormones are synthesized by smooth endoplasmic reticulum.
Of the above statements:

Match the Column-$I$ with Column-$II$.

Column-$I$	Column-$II$
$(a)$ Golgi apparatus	$(i)$ Synthesis of protein
$(b)$ Lysosomes	$(ii)$ Trap waste and excretory products
$(c)$ Vacuoles	$(iii)$ Formation of glycoproteins and glycolipids
$(d)$ Ribosomes	$(iv)$ Digesting biomolecules

Choose the right match from the options given below.

How many of the following structures are membrane-bound?
Endoplasmic reticulum,Golgi apparatus,Ribosomes,Lysosomes,Mitochondria,Microbodies,Centrioles,Nucleolus,Vacuoles

Which of the following statements are correct?
$(i)$ In prokaryotic cells,a special membranous structure formed by the extension of the plasma membrane into the cell is known as polysome.
$(ii)$ The smooth endoplasmic reticulum is the major site for synthesis of glycoproteins.
$(iii)$ $RuBisCO$ is the most abundant protein in the whole biosphere.
$(iv)$ Mitochondria,chloroplasts,and peroxisomes are not considered as part of the endomembrane system.

In the given figure,what do $a$ and $b$ represent respectively?