Respiration In Plants — BIOLOGY STD 11 Science — Question

Write the characteristics of heartwood and sapwood.

Explain in brief the nervous system of cockroach.

Kritika's biology teacher explained the different phases of plant growth in her class. She taught that growth of plants takes place in three successive steps or phases from germination to maturation phase. Kritika reached home and asked her elder sister, a biology post-graduate student to clarify the phases in detail. Kritika's sister told her that she will explain the complete process with the help of experimentation. She took few seeds of pea and germinated them on a circular filter paper, soaked with water in a petri-dish. After two days of growth, she picked up a couple of seedlings with straight radicle and marked it from tip to base with the help of a waterproof ink and again placed the seedlings on moist filter paper to allow them to grow.

1. Mention different phases of growth in plants?
2. List the conditions required for growth.
3. What values are reflected from nature of Kritika's sister?

Distinguish between cell membrane and cell wall.

Explain how hypothalamus functions as an endocrine gland?

List out the important functions of connective tissue.

Find out a qualitative test for proteins, fats and oils, amino acids and test any fruit juice, saliva, sweat and urine for them.

What is the significance of step-wise release of energy in respiration?

Auxins are growth hormones capable of promoting cell elongation. They have been used in horticulture to promote growth, flowering and rooting. Explain the meaning of the following terms related to auxins.

1. Auxin precursors.
2. Anti-auxins.
3. Synthetic auxins.

Mention six characteristic features of dinoflagellates.