Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

Explain with the help of suitable examples the three different ways by which organisms overcome their stressful conditions lasting for short duration.

Why are the conventional methods not suitable for the assessment of biodiversity of bacteria?

Give examples of termination codons. Why are they known as termination codons?

Draw the sketches of a zoospore and a conidium. Mention two dissimilarities between them and at least one feature common to both the structures.

Given below are the events that are observed in an artificial hybridisation programme. Selection of parents → Emasculation → Bagging → Collection of pollen from other male plant → Dusting of pollen on stigma — Rebagging.
While, planning for crop improvement involving dioecious plants, which of the above mentioned steps would not be relevant?

Explain Homologous and Analogous organs with example.

Mention three physical properties and three chemical properties of soil, that determine the type of vegetation in a given region.

State Mendel’s principle of segregation.

Human blood group is a good example of multiple allelism and co-dominance. Justify.

When a cross in made between tall plant with yellow seeds (TtYy) and tall plant with green seed (Ttyy), what proportions of phenotype in the offspring could be expected to be,

1. Tall and green.
2. Dwarf and green.