Which of the following is not true for inbreeding?
It causes inbreeding depression after a few generations
It always increases the productivity.
It is used to produce a pure line.
It leads to homozygosity
B.
It always increases the productivity.
Inbreeding leads to increase in homozygosity. In recessive alleles, it may cause expression of harmful effects. It may also lead to loss of fitness in progenies, thus decrease productivity in some cases.
Sporopollenin is a constituent of pollen exine. It can be degraded by the action of
enzymes
high temperature
strong acids
cannot be degraded
After doble fertilization, a mature ovule has
1 diploid and 1 haploid cell
1 diploid and 1 triploid cell
2 haploid and 1 triploid cell
1 haploid and 1 triploid cell
Assertion : Commelina shows cleistogamy.
Reason : This reduces chances of inbreeding.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
What is the characteristic of tapetum
It does not store food.
It is multi-nucleated.
It is multi-layered structure.
It nourishes the megaspore
The given figure shows L.S of the seed of maize. What do A, B, C and D represent?
A : endosperm, B : scutellum, C : plumule, D : coleoptile
A : scutellum, B : pericarp, C : radicle, D : coleoptile
A : endosperm, B : scutellum, C : radicle, D : coleorrhiza
A : scutellum, B : pericarp, C : plumule, D : coleorrhiza