Question

Extranuclear genes are present in
A.Cytoplasm
B.E.R and cytoplasm
C.Ribosome and cytoplasm
D.Mitochondria and cytoplasmic particles

Answer 1

Hint: A gene is the unit of heredity and inheritance. Genes are the sequence of nucleotides in DNA or RNA that encodes the product which can be either RNA or protein.

Complete answer:
Extranuclear genes:
Extranuclear genes are the genes that present somewhere in the cell outside the nucleus.
These genes are found in most eukaryotic organisms.
These extranuclear genes are present in the cytoplasmic organelles called mitochondria, and chloroplasts.
The transmission of extranuclear genes from the parents to the offspring is called the extranuclear inheritance or cytoplasmic inheritance.
Some of the extranuclear genes code proteins.
The extranuclear genes are inherited by the offspring via cytoplasm of the gamete because only cytoplasm contain the organelles mitochondria or chloroplasts.
In humans, the extranuclear genes contained in the mitochondria are passed from generation to generation through the maternal parents in the ovum.
Additional information:
Mitochondria – Mitochondria are also called as the powerhouse of the cell. This is because in mitochondria, aerobic respiration takes place. Electron transport chain take place in the mitochondria which is responsible for the production of energy rich molecule i.e. ATP. As a result of aerobic respiration ATP (adenosine triphosphate ) gets synthesized. ATP is an energy rich molecule. Mitochondria is only present in the eukaryotic cells.
Chloroplasts – Chloroplasts are the cell organelles that are present in the plants and algae. These organelles help in conducting the process of photosynthesis (the process by which plants make their own food with the help of water, carbon dioxide and sunlight). Chloroplasts have the photosynthetic pigments called chlorophyll that capture the energy from sunlight.
Therefore, it has been clear from the above discussion that the extranuclear genes are present in the mitochondrial and cytoplasmic particles.

Hence the correct answer is option(D)

Note: The term gene was introduced by Danish botanist plant physiologist and geneticist Wilhelm Johannsen in 1909. The genetic information passed from parents to the offsprings in the form of the genes. The genes make up different genetic sequences which are called genotypes.