Class 12th Biology 2017 Set1 Delhi Board Paper Solution
How does the application of the fungal genus, Glomus , to the agricultural farm increase the farm output?
The use of Glomus to agricultural field increases the farm output by increasing the nutrient availability to the crops. Many members of the genus, Glomus form mycorrhiza. The fungal symbiont in these associations absorbs phosphorus from soil and passes it to the plant. Plant having such association show other benefits also, such as:
1. Resistance to root borne pathogens
2. Tolerance to salinity and drought
3. Overall Increase in plant growth and development
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Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
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(c) Fertilization is __________ in humans. (external/internal)
(d) Male and female gametes are __________. (diploid/haploid)
(e) Zygote is __________. (diploid/haploid)
(f) The process of release of the ovum from a mature follicle is called__________.
(g) Ovulation is induced by a hormone called the __________.
(h) The fusion of male and female gametes is called _____________.
(i) Fertilisation takes place in _____________.
(j) Zygote divides to form _____________which is implanted in uterus.
(k) The structure which provides vascular connection between fetus and uterus is called ____________.