What is a centromere? How does the position of the centromere form the basis of the classification of chromosomes? Support your answer with a diagram showing the position of the centromere on different types of chromosomes.

Describe the structure of the following with the help of labeled diagrams.

(i) Nucleus

(ii) Centrosome

Both lysosomes and vacuoles are endomembrane structures, yet they differ in terms of their functions. Comment.

What are nuclear pores? State their function.

Cells are the basic unit of life. Discuss in brief.