Question

Assertion- Nucleus plays an important role in cellular reproduction and cellular functions.
Reasons- Nucleus contains chromosomes which are made up of DNA which contain information for constructing and organising cells.

a) If both Assertion and Reason are the true and Reason is the correct explanation of Assertion.
b) If both Assertion and Reason are true but the Reason is not the correct explanation of Assertion.
c) If Assertion is true but Reason is false.
d) If assertion is false but Reason is true.​

Answer 1

Answer:

Prokaryotic cells have a cell wall surrounding the cell membrane. The fluid matrix filling the cell is the cytoplasm. There is no well-defined nucleus. The genetic material is basically naked in the cytoplasm, not enveloped by a nuclear membrane. The nuclear membrane is found in eukaryotes. The prokaryotic cells lack mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, microtubules, microfilaments, and centrioles. Cytoplasmic streaming, also called cyclosis, is the directed flow of cytosol (the liquid component of the cytoplasm) and organelles that aids in the delivery of organelles, nutrients, metabolites, genetic information, and other materials to all parts of the cell. In prokaryotes, cytoplasm does not show cyclosis or streaming movements.

So, the answer is A.

Answer 2

Both Assertion and Reason are true but the Reason is not the correct explanation of Assertion.

• Genetic material is present in the nucleus. In the cell, the DNA is mostly required for cellular functions as well as cellular reproduction. Genetic material is then transmitted by the same to the daughter cells and synthesis of several proteins are needed for the reproduction of the cells.
• Chromosomes in the nucleus consists of proteins and DNA. Molecules of the DNA consists of the required information for organizing and constructing the cells.
• Genes are referred to as the segments of DNA that are functional. The DNA is found to be as a portion of chromatin material in a cell that is not being distributed.

Hence, C is the correct option.