ICSE 2016 - Class 10 Biology Board Question Paper

Class-10 Biology Board Question Paper - ICSE 2016

The question paper carries total of 80 marks and is divided into two sections, each carrying 40 marks. From Section-I, all questions have to be answered whereas from Section-II, can attempt any 4 questions.

General Instructions:

• Answers to this paper must be written on the paper provided separately. 
• You will not be allowed to write during the first 15 minutes. 
• This time is to be spent in reading the question paper. 
• The time given at the head of the paper is the time allowed for writing the answers.

Mystery behind different eye colors and patterns

Each human being has different eye color - some have brown eyes, some have black, green or blue eyes.  What is the mystery behind different eye colors - black, brown, blue or green? What defines unique pattern seen in our eyes? Why eye color and pattern of one person differs from another? Are our genes responsible for eye color? Is eye color inheritable from parent to offspring?

Let's explore further to find out answers to the above questions.

Mendel's Law of Segregation or Law of Purity of Gametes

Law of Segregation is the second Law of Inheritance given by Mendel which was formulated based on the observations noted down while performing Monohybrid cross. 

When self-hybridization of F1 progeny is performed, we could see that in F2 generation, the phenotypic ratio is obtained as 3 : 1 (Tall : Dwarf) whereas genotypic ratio is obtained as 1 : 2 : 1 (Pure tall : Hybrid tall : Pure recessive).

Thus, we could observe that the recessive character which disappeared in F1 generation, reappears in F2 generation and shows that alleles or genes do not mix with one another and separated pure during gamete formation which is Law of Segregation or Law of Purity of Gametes.