Angiosperms are plants that produce flowers, which are nothing but the reproductive machinery of the plant. The life cycle of angiosperms begin with pollination and end in the formation of fruits which contains seeds that germinate into new plants which mature till they reach the flowering stage, thereby, completing a full circle. Now, before we discuss the details of the life cycle of angiosperms, let’s check out the different parts of the flower that participate in the reproductive cycle to continue the species even after the parent plant dies or withers away.

Parts of Flower that Participate in the Reproduction Cycle

Following are those parts of a flower that actually facilitate the entire reproductive mechanism which results in the production of seeds. This seed, when it finds a combination of favorable environmental conditions (right kind of soil, adequate moisture, sufficient amount of air and temperature, etc.), sprouts into seedlings, which then grow into plants. On reaching maturity, the new, young plants grow flowers themselves, and the process starts all over again.

Stamen: This is the male reproductive part of a flower, and it consists of a long, slender filament, which can be seen occurring as a number of long, pliant stalks arranged in a circle on the inside of the flower, surrounded by petals. These filaments are topped with small, often oblong, head like structures known as anthers. The stamen is where the pollen grains are produced, and these pollen grains are carried from the anthers to the female reproductive organ, where they fertilize the ovules, but we’ll discuss that later. So, to put it simply, male parts of a flower = stamens = filaments + anthers!
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Do you know what is common between curd, wine and beer? They are all formed by the process of fermentation. But what is fermentation? A simple fermentation definition can be: the process of breaking down of complex substances into a simpler form. The history of fermentation is very old. The process of fermentation was used in making beverages such as beer and wine, since as early as the year 7000 BC. Later on, the process was used to make many milk products like curd and cheese. The science of fermentation is known as zymology, and Louis Pasture was the first zymologist who is known for his research on yeast and the fermentation process. So let’s find some more information on the fermentation process in the following paragraphs.

What is Fermentation in Biology?

In biology, the fermentation process is actually a conversion of sugar into acids or alcohol with the help of bacteria or yeast. The bacteria help in the conversion of sugar into acid, and the yeast is used for the alcohol production. Many people wonder, is fermentation aerobic or anaerobic? The answer to this is that fermentation takes place in anaerobic conditions or in the absence of oxygen. The process of fermentation initially resembles the process of glycolysis. In the first step of glycolysis, glucose is broken down into pyruvic acid, ATP and NADH. After this process the NADH is further re-oxidized and CO2 and the end product which can be either alcohol or acid, depending upon the organism performing the fermentation process, is released. So, we can say that fermentation is a chemical process.

Fermentation Examples

Following are some examples of fermentation, which will help you to understand the process and uses of it.

Beer is one of the best examples of anaerobic fermentation. It is made out of grains like wheat, barley, etc. The grain is dried and then mashed properly. This is then mixed with hot water. Then this mixture is kept in a fermentation vessel and then yeast is added. The vessel is then left for a few weeks in anaerobic conditions. In this condition, the yeast eats the sugar or carbohydrates and forms alcohol. After a considerable period of time, the beer is taken out from the vessels, filtered and then packed in the bottles. Read the rest of this entry »

I do not believe any branch of science has ever given rise to as many controversies and controversial debates as evolution has. But even with so many controversies, “Nothing in biology makes sense except in the light of evolution” (Theodosius Dobzhansky). When we think of evolution, the first name to strike even someone who is not from a biological sciences background would be Charles Darwin. Not a word can be written on evolution without mentioning the name of this pioneering evolutionary biologist. His work On the Origin of Species has been the topic of much discussion ever since it was first published.

Of the many concepts that were elaborated in this book (like survival of the fittest) one was Darwin’s Principle of Divergence. The other term – Convergent Evolution – is often regarded as the opposite of Divergence. However, convergent evolution was only a play of words that evolutionary biologists came up with to explain one of their many observations; it has got nothing to do with divergence as such. Here is a brief account of convergent evolution vs. divergent evolution. However, for the ease of understanding, I will first explain divergent evolution and then move onto convergent evolution.

Divergent Evolution

Imagine evolution of life to be a process like the flowing of a river. As it leaves the mountain, it will take its due course and meander about. If a boulder were to obstruct its flow into a crevice, it would take a turn around the crevice. If however a big enough boulder were to stand in between its path, the river would split into two and give rise to two new smaller rivers, each of which would meet its separate fates as it flowed down the mountain.

This is exactly what divergent evolution is all about. The boulder represents something known as ‘natural selection’. Natural selection is more of an outcome of natural pressure that organisms find themselves subject to (typically pressure of competition, pressure of mating preferences of (usually) the females of the species, etc.) rather than the actual pressure. It is the result rather than the process. However, it is now interchangeably used as cause and effect. Read the rest of this entry »