Which of the following causes variations in the genetic material of progeny?

(i) Sexual reproduction

(ii) Asexual reproduction

(iii) Mutations

(iv) Epigenetic changes

The correct answer is  (i) and (iii).Key Points

• In the process of sexual reproduction, the genetic material comes from both parents.
  • This is why there are variations in the offspring that occur due to the genetic material of the two parents of the same species.
• Genetic variations can arise from gene variants called mutations.
  • In this genetic material is rearranged as a cell is getting ready to divide (known as genetic recombination).
• Asexual reproduction generates offspring that are genetically identical to a single parent. 
• Hence Sexual reproduction and Mutations cause variations in the genetic material of progeny.

Confusion Points

• Epigenetics is the study of how your behaviors and environment can cause changes that affect the way your genes work.
• Unlike genetic changes, epigenetic changes are reversible and do not change your DNA sequence.

Additional Information

• Genetic material consists of DNA deoxyribonucleic acid and RNA ribonucleic acid genes.
• DNA is a double helix made of nucleotides joined together. Each joined nucleotide represents a gene.
• There are 4 base pairs in DNA [A, T, G, C]
  • A = adenine, T = thymine, G = guanine, C = cytosine
• Whereas RNA Is single-stranded and bases are [A, U, G, C]
  • A = adenine, U = uracil, G = guanine, C = cytosine
• Chromosomes are densely packed long strands of DNA.