REPEATER 2024 — BIOLOGY STD 12 Science — Question

Is haemophilia in humans a sex-linked or an autosomal disorder? Workout a cross in support of your answer?

Mention the number of cells in the following stages:

S. No	Embryonic stages	No. of cells
(i)	Zygote	______________
(ii)	Morula	______________
(iii)	Blastocyst	______________

State the role of AUG codon at the 5' end and UAG at 3' end of a certain mRNA during translation.

Bacteria cannot be seen with the naked eyes, but these can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes under a microscope, which sample would you carry and why?

1. Why are the plants raised through micropropagation termed as somaclones?
2. Mention two advantages of this technique.

Lifestyle diseases are increasing alarmingly in India. We are also dealing with large scale malnutrition in the population. Is there any method by which we can address both these problems?

Explain how did von Helmont supported the theory of spontaneous generation?

By taking two examples explain how has bio-fortification helped in improving food quality.

Draw a diagram of a matured microspore of an angiosperm. Label its cellular components only.

Name two drugs obtained from poppy plant. "These drugs are medically useful, but are often abused". Taking the mentioned examples justify by giving reasons.