Question

12.
13.
Describe the structure of chromosome. (U)
Name the organelles in which following structures are found: (K)
a) Cisternae b) Cristae c) Thylakoids d) Nucleolus
c) Thylakoids d) Nucleolus e) Tonoplast​

Answer 1

12. ⭐ Every chromosome has a essential primary constriction(centromere) on kinetochores.

⭐ Centromere holds two chromatids of a chromosome.

⭐ Based on position, chromosomes can be classified into four types

• Metacentric
• Sub-metacentric
• Acrocentric
• Telocentric

13. a) Cisternae - Golgi apparatus

b) Cristae - Mitochondria

c) Thylakoids - Chloroplast

d) Nucleolus - Nucleus

e) Tonoplast - Vacuoles

Answer 2

Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure. Chromosomes are not visible in the cell's nucleus—not even under a microscope—when the cell is not dividing. ... DNA and histone proteins are packaged into structures called chromosom