What causes a green plant exposed to the light on only one side, to bend toward the source of light as it grows?
Green plants need light to perform photosynthesis.
Green plants seek light because they are phototropic
Light stimulates plant cells on the lighted side to grow faster
Light stimulates plant cells on the lighted side to grow faster
In a ring girdled plant
the shoot dies first
the root dies first
the shoot and root die together
the shoot and root die together
B.
the root dies first
In a ring girdled plant, the root dies first. A ring of bark is cut from the stem. It also removes phloem. Nutrients collect above the ring where the bark also swells up and may give rise to adventitious roots. Growth is vigorous above the root. The tissues below the ring not only show stoppage of growth but also begin to shrivel (contract). Roots begin to starve first if the ring is not healed, after sometime roots will die, which will kill the whole plant.
Which one gives the most valid and recent explanation for stomatal movements?
Transpiration
Potassium influx and efflux
Starch hydrolysis
Starch hydrolysis
The hilum is a scar on the
seed, where funicle was attached
fruit, where it was attached to pedicel
fruit, where style was present
fruit, where style was present
Transmission tissue is characteristic feature of
hollow style
solid style
dry stigma
dry stigma
Which one of the following is a wrong statement regarding mutations?
Deletion and insertion of base pairs cause frame-sheft mutations
Cancer cells commonly show chromosomal aberrations
UV and Gamma rays are mutagens
UV and Gamma rays are mutagens
A test cross is carried out to
determine the genotype of a plant at F2
predict whether two traits are linked
assess the number of alleles of a gene
assess the number of alleles of a gene
Read the following four statement.
1. In transcription, adenosine pairs with uracil
2. Regulation of lac operon by repressor is referred to as positive regulation.
3. The human genome has approximately 50,000 genes.
4. Haemophilia is sex-linked recessive disease.
How many of the above statements are right?
Two
Three
Four
Four
What is the function of germ pore?
Emergence of radicale
Absorption of water for seed germination
Initiation of pollen tube
Initiation of pollen tube
Which one of the following statements is wrong?
When pollen is shed at two-celled stage, double fertilization does not take place
Vegetative cell is larger than generative cell
Pollen grains in some plants remain viable for months
Pollen grains in some plants remain viable for months