Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

A student was simulating Urey and Millers experiment to prove the origin of life. The set up used by the student is given.

1. Find out the reasons why he could not get desired results.
2. What conclusion was drawn by Urey and Miller through this experiment?
3. Compare the conclusion drawn with the theory of spontaneous generation.

A homozygous tall pea plant with green seeds is crossed with a dwarf pea plant with yellow seeds.

1. What would be the phenotype and genotype of F, generation?
2. Work out the phenotypic ratio of F, generation with the help of a punnett square.

Prabha has seen huge garbage dumps outside your school which are not being regularly disposed of by MCD. Prabha discusses the problems with school mates and decide to organize rally to spread awareness among local people about public hygiene.
→ Prepare two slogans for rally
→ Name any two infectious diseases which may spread due to such unhygienic conditions at public place

Mention the advantages of selecting pea plant for experiment by Mendel.

Where is an 'operator' located in a prokaryote DNA? How does an operator regulate gene expression at transcriptional level in a prokaryote? Explain.

List three symptoms of high altitude sickness and state three adaptations to overcome it.

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 with the help of a microscope, which sample would you carry and why?

Name the kind of organisms which constitute the pioneer community of xerarch and hydrarch succession, respectively.

Explain the difference between predation and Parasitism.

Give a brief description of the different types of biodiversity in concise words.