Pollinia and massulae, Biology

Assignment Help:

Pollinia and Massulae

In most cases the pollen grains of each tetrad become separated from one another and they lie freely in the pollen sac. In some plants, mostly members of Ericaceae, the pollen grains remain in tetrads even when mature. In certain plants, such as Acacia, the tetrads are stuck together as groups, which may contain as many as 64 pollen grains. In some other plants, such as members of the Asclepiadaceae, all the pollen grains of a sac are united in a single compact mass such a mass is termed a pollinium. In some members of the family Orchidaceae the anthers produce groups of pollen grains which are loosely jointed among themselves, usually by means of viscin threads. These groups are called as massulae.


Related Discussions:- Pollinia and massulae

Endosperm, 1. What are the examples of helobial endosperm

1. What are the examples of helobial endosperm

List the exact sizes of the fragments of digests, (1)  The 7,893 bp plasmid...

(1)  The 7,893 bp plasmid shown below was digested with a series of restriction enzymes (P = PstI, B = BamHI, S = SalI, X = XbaI). Answer the questions below.  a) Indicate

Explain fats requirements during thyphoid, Explain fats requirements during...

Explain fats requirements during thyphoid Fats: Use of fats should be in moderation. This is because the typhoid patient has a compromised ability to digest and assimilate due

What is the embryonic development called, What are the cells produced in th...

What are the cells produced in the first stage of the embryonic development called? The cells that result from the cleavage (the first stage of the embryonic development) are k

Synthesis of hormones - testies, Synthesis of Hormones - Testies Leyd...

Synthesis of Hormones - Testies Leydig cells and the Sertoli cells are the steroid hormone synthesising cellular sites of the testis. Leydig cells are the major source of the

Kinds of succession - ecology, Kinds of Succession - Ecology The ecolo...

Kinds of Succession - Ecology The ecological succession can be broadly classified into two kinds, on the basis of the nature of the habitat. Figure: Kinds of Success

Explain principle osazone test or phenylhydrazine reaction, Explain Princip...

Explain Principle Osazone Test or Phenylhydrazine Reaction? Phenylhydrazine reacts with carbonyl compounds in neutral or slightly acidic medium to give phenylhydrazones. These

Explain phylum platyhelminthes, Phylum platyhelminthes (13,000 species Fla...

Phylum platyhelminthes (13,000 species Flatworm) The body is flattened. Gastrovascular cavity is branched, dense bodies with many cell layers, mouth but no anus. Hermaphrodite

Individual neurons communicate, A human is better able to ride a bike becau...

A human is better able to ride a bike because individual neurons communicate information faster than modern computer chips. true or false

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd