HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Important Questions for Biology

State any two symptoms of Down’s syndrome.

Describe the structure of chromosomes with a suitable diagram.

________ shows haplo-diploid type of sex-determination.

Classify the chromosomes on the basis of position of centromere.

Attempt any TWO of the following: 

‘The gene for sickle cell anaemia in homozygous condition is lethal and produces sickle cell trait in heterozygous carrier’. Explain. 

Give the importance of heterocyst in cyanobateria.

Which of the following traits is never observed in a human female? 

What do sex linked traits appear in males than in females? 

Distinguish between X and Y chromosomes.

With the help of a chart, explain the method of sex determination in honeybees.

Which one of the following is a true pleiotropic gene?

Drone of the honeybees shows haploid number of chromosomes. Illustrate. 

Describe the structure of sex-chromosomes. 

In which livings, female decides the sex? Give two examples.

Give one example of the autosomal recessive disorder.

What are X-linked genes?

Explain the haplo-diploid method of sex determination in the honey bee.

In human beings 45 chromosomes/single X/XO abnormality causes ______.

How many linkage groups are present in Drosophila melanogaster?

Write a note on sex linkage.