Question

What is the approximate size of nucleus in a typical mammalian cell?
A) 2.2 meter
B) 1.2 meter
C) $10^{-4}$ meter
D) $10^{-6}$ meter

Answer 1

Hint:All organisms have a basic biological, structural and functional unit called a Cell.
Cells contain various components like cytoplasm, cell membrane, nucleus etc.
Nucleus is a cell organelle that contains genetic material that regulates growth and metabolism of the cell.

Complete answer:
 A mammalian cell size varies from 10 to 100 micrometers . Mammalian cells are very sensitive as they do not contain cell walls. It has subcellular divisions called organelles and a double membrane bound nucleus.
Nucleus is the largest cell organelle in the cell. The inner membrane constitutes the nucleus and outer membrane is connected with a rough endoplasmic reticulum. About 10% of the cell is occupied by the nucleus of size of average diameter of 10-6 micrometer.

Therefore the correct answer is (D) $10^{-6}$ meter.

Additional information:
>Like cytoplasm in a cell, the nucleus contains nucleoplasm that holds the genetic material and other components of the nucleus.
>It coordinates the activities of cells like cell division and synthesis of proteins.
>The significant role of the nucleus is to regulate the heredity characteristics as it contains the genetic material (DNA) during the cell cycle.

Note:Remember that there is a chance of malfunctioning of the cell as it contains the nucleus which carries genetic material and is susceptible to mutation.