Pollen stigma interaction - stigma, Biology

Pollen Stigma Interaction - Stigma

The Stigma After landing on the stigma pollen grain germinates, and produces a pollen tube that carries the male gametes. The stigma has been classified into two principal types depending on the presence or absence of stigmatic exudate at the time of pollination:

  1. The wet stigma is covered by a sticky secretion, e.g., Aegle marmelos and Petunia hybrida, and
  2. The dry stigma lacks any secretion, e.g., cotton.

EM observations indicate that the exudate is secreted by the ER and it is extruded by exocytosis. The diagrammatic representation of the mechanism involved is shown in Figure. In some plants such as Lilium, the stigma is non-secretory. The exudate which is present on stigma is, in fact, secreted by the stigmatic papillae and those present in the stylar canal emanate from the style.

Posted Date: 1/23/2013 3:03:28 AM | Location : United States

Related Discussions:- Pollen stigma interaction - stigma, Assignment Help, Ask Question on Pollen stigma interaction - stigma, Get Answer, Expert's Help, Pollen stigma interaction - stigma Discussions

Write discussion on Pollen stigma interaction - stigma
Your posts are moderated
Related Questions
Q. How do taenias obtain food and make gas exchange? The Tapeworms have sucking and hooks structures on their heads (scolex) that fixate the parasite in the gut wall these stru

ISOZYMES Sometimes an  enzyme present  in  the  same  organism is  found  to  have different molecular forms but  catalyzing the  same  reaction. These are called  isozymes. Th

What is the name of the terminal portion of the axon? The terminal portion of the axon is known presynaptic membrane. Through this membrane neurotransmitters are released into

Q. Drugs and Insulin used in diabetes? When diet, exercise or even weight reduction do not improve the diabetic symptoms and blood sugar levels, the uses of hypoglycemia drugs

Class of Crustacea - Copepoda Copepoda is a huge class of small (1-5mm) crustaceans occupying both marine and freshwater environments. Copepods form the several abundant and c

Write functions of epithelial tissue

C dna is made from a mature m rna of eukaryotic cell with the utilization of enzyme called as reverse transcriptase. Steps in c dna creation 1. m rna is made and purified f

Define Future challenges for dynamical network? Graph theory is an old field of mathematics where biological applications are driving new advances. Mathematicians are supplemen

What is Demographic Transition? The whole process of change with regard to population size and characteristics is called demographic transition. In order to understand this ter

Explain the Physical Methods to Control Microorganisms? The physical methods to control microorganisms involve heat, filtration or radiations. Figure illustrates these methods.