Fine structure of pollen tubes grown in vitro, Biology

Fine Structure of Pollen Tubes Grown in Vitro

The growth in pollen tubes is exclusively restricted to the tip. Cytochemical analysis reveals the pollen tip zone to be rich in RNA and protein. This zone has numerous vesicles and an elaborate network of smooth membranes. The vesicles appear to rise from the ends of dictyosome cisternae. They coalesce with one another and ultimately contribute their membrane and contents to the compartmented cap covering the growth zone at the tip. The cap and the vesicles contain pectin and the RNA resides in the smooth membranes.

In the region behind the tip the tube contains those organelles present in pollen before germination, as well as numerous amyloplasts. The tube wall is thin (tubes growing in pistil have complex wall). Cellulose is the primary wall component. The cytoplasm of pollen tubes growing in vitro lack microtubules. EM shows that the generative cell is surrounded by its own distinct wall and the cytoplasm is different from the grain proper. It contains a small number of poorly developed organelles which possess little storage material.

Posted Date: 1/23/2013 4:29:12 AM | Location : United States

Related Discussions:- Fine structure of pollen tubes grown in vitro, Assignment Help, Ask Question on Fine structure of pollen tubes grown in vitro, Get Answer, Expert's Help, Fine structure of pollen tubes grown in vitro Discussions

Write discussion on Fine structure of pollen tubes grown in vitro
Your posts are moderated
Related Questions
Congenital Syphilis  A positive serological test for syphilis in a newborn without stigmata of syphilis may be due either to passive transfer of maternal antibodies or to prena

Causes of Cancer We know earlier that a malignant tumor is a large aggregation of cancer cells, all of them descended from a single founder cell that was once a normal cell wi

What are the flat bones and the long bones? The major bones of the body may be divided as flat or long bones (there are bones not classified into these categories). Such as fla

Characteristics of River Systems The basic function of the rivers is to convey surplus rain water from land to sea. Annually the rivers carry fresh water, equivalent to 25 cm

Lakes - Lentic Ecosystems Most lakes occur in regions which have recently been subjected to geological changes; say within the past 20,000 years. However, a few lakes, such a

Hypothetical question. A new biotech company intends to clone the gene encoding the ABA 8-hydroylase enzyme, an important protein regulating plant hormone degradation that control

A cell frequently wants to secrete larger molecules than can be accommodated through the transport systems dealt with in Topic E3. Exocytoses get to the movement of proteins out of

Estimate the Results of Tetralogy of Fallot? In excellent centres, the mortality is reported one per cent or less. In infants and babies with low weight, higher mortality is ex

Define the Insulin resistance - Obesity? Insulin resistance is a condition in which your body cells cannot utilize insulin efficiently although sufficient amounts are secreted