D. The macronucleus does not disintegrate during conjugation.
The macronucleus contains the working copies of genes needed to support an enormous cell. It is formed by a division of the fused diploid nucleus after conjugation followed by multiple rounds of internal gene replication which does not occurs in the micronucleus.
On the Galapagos Islands, Darwin also saw several different types of finch, a different species on each island. ... Finches that ate small nuts and seeds had beaks for cracking nuts and seeds. Darwin noticed that fruit-eating finches had parrot-like beaks, and that finches that ate insects had narrow, prying beaks.
Biological macromolecules are important cellular components, they have a wide array of functions necessary for survival and growth of living organisms. There are four major classes of biological macromolecules
-carbohydrates
-lipids
-proteins
-nucleic acids.
<span>Plants without vascular system are non-vascular plants. Non-vascular plants have no xylem and no phloem.
Non-vascular plants include algae, bryophytes, moss grass, liverworts and hornworts.
The answer to this item is moss. Moss is a non-vascular plant which has no seeds and no flowers. It uses spores in reproduction.</span>
hope this helps
I do think that they close to not allow too much of either water or air from entering.
the hollow tube allows water to flow easily.
https://www.bbc.co.uk/bitesize/guides/z28g7p3/revision/1