The organelle that controls all activities in a cell:

1. Nucleus
2. Vacuole
3. Plastid
4. Cytoplasm

A cell that is spherical in shape is:

1. White blood cell
2. Nerve cell
3. Red blood cell
4. Amoeba

The type of microscope that we use in our school laboratories is :

1. Simple microscope
2. Electron microscope
3. Compound microscope
4. Both (1) and (2)

Which of the following lens is used in a simple microscope ?

1. A single biconcave lens
2. Two convex lenses
3. A single biconvex lens
4. Two concave lenses