Define cleavage in fertilized egg and give its two main characteristic features. Describe the mechanism of cleavage in the fertilized egg.

With the help of a flow chart explain the processes involved in the initiation of flower primordial.

Prepare a detailed account on types of incompatibility, its biological significance and methods to overcome it.

Write detailed notes of the following:

i) Physiological effects of plant growth regulators

ii) Characteristics determining economic importance of wood

iii) Syngamy and triple fusion

iv) Autochory

Draw clear and labelled diagrams for the following:

i) Aleurone cells of a cereal with aleurone grains

ii) Diagrammatic representation of secondary growth in a dicot stem of four years.

iii) T.S. of a stem showing heartwood and sapwood

iv) Endosperm with chalazal haustorium

v) Dimorphic tapetum

in-vitro clonal propagation.

The meristems that produce secondary tissues.

The state of suspended growth and metabolism.

The response of plants to touch.

Plants that flower irrespective of the length of the day.

A chain of cells that attaches the embryo to the embryo sac.

The cell of the pollen grain that divides to form sperms.

The nutritive cell surrounding the nucellus and that develop from the inner-most layer of the integument.

A wall layer of anther that helps in its dehiscence.

A mass of cells that divides to form the archesporial mother cells

Discuss theories proposed for mechanism of translocation of food in phloem with proper diagram.

What are the main functions of stomata? Describe the mechanism of opening and closing of stomata with labelled diagram.

Describe practical application of plant hormones.

Discuss why photorespiration is called “necessary evil”.

Describe how Photosystem I and Photosystem II work together to produce NADPH with proper diagram.