Question
Give an account of polyembryony.
✓
Answer
Polyembryony:
- Polyembryony is the occurrence of more than one embryo in a seed which consequently results in the emergence of multiple seedlings.
- The additional embryos result from the differentiation and development of various maternal and zygotic tissues associated with the ovule of the seed.
- In adventive polyembryony, an embryo develops directly from the diploid cell of nucellus and integuments as in Citrus.
- In cleavage polyembryony, zygote proembryo sometimes divides (cleaves) into many parts or units. Each unit then develops into an embryo.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
How do flowers of Vallisneria get pollinated?
Distinguish between Asexual and Sexual reproduction with reference to:
(i) Cell division
(ii) Genetic makeup
(i) Cell division
(ii) Genetic makeup
Where are fimbriae present in a human female reproductive system? Give their function.
In an agricultural field there is a prevalence of the following organisms and crop diseases which are affecting the crop yield badly:
- White rust.
- Leaf and stripe rust.
- Black rot.
- Jassids.
Why is colostrum a boon to the new born baby?
Make a chart (with diagrammatic representation) showing a restriction enzyme, the substrate DNA on which it acts, the site at which it cuts DNA and the product it produces.
What is seed dormancy? What is its significance?
Apart from being part of the food chain, predators play other important roles. Mention any two such roles supported by examples.
What are untranslated regions (UTRs)?
Answer the questions based on the dinucleotide shown below:
- Name the type of sugar, the guanine base is attached to.
- Name the linkage connecting the two nucleotides.
- Identify the 3' end of the dinucleotide. Give a reason for your answer.