STD 11 - 8. Cell the unit of life — NEET STD 11 Science — Question

Why is a capsule advantageous to a bacterium ?

Assertion: In dicotyledonous stems open vascular bundles present.
Reason: Cambium is present between phloem and xylem and it possess the ability to form secondary xylem and phloem tissues.

Generally the food chain has how many trophic levels

Which protozoan is unlikely to have a contractile vacuole

Assertion: Meiosis results in production of haploid cells.
Reason: Synapses occurs during leptotene.

Dormancy of seed is broken by

Which of the following are not correct ?
(i) Oxygen helps in releasing metabolic energy essential for growth activities.
(ii) Nutrients are required by plants for the synthesis of protoplasm and act as source of energy.
(iii) Light and gravity affect certain stages of growth.
(iv) Water oxidizes glucose to provide energy
(v) Long day plants flower if the night length shorter than a critical period.
(vi) Short-day plants flower when night length exceeds a critical dark period.
(vii) The process of flowering does not occur in dayneutral plants.
(viii) 17,500 new cells are produced per hour by a single maize root apical meristem.
(ix) With the help of length, growth of pollen tube is measured.
(x) The growth of the leaf is measured in terms of volume.
(xi) Cells in a watermelon may increase in size by upto 3,50,000 times.
Choose the correct option given below :-