Showing posts from September, 2006

Spaceships of God

We now know that the sun will eventually start to cool down, expand and explode. Mankind hopes that well before that it will escape from earth and colonize other planets so that the human race as it exists on earth can be preserved. This is easier said than done. Interplanetary travel from one habitable planet to another is a daunting task for the most advanced of civilizations and even if it did become possible one may find on arrival on another planet that the precise chemical composition of the new planet has made all available food toxic. The mineral compositions of planets vary.

Mankind need not despair. Nature has devised a better plan. In fact it has been in place ever since the universe has existed. When a star begins to cool down, most forms of life are frozen into extinction. However many bacteria, including the most useful ones have the ability to go into frozen hibernation and do so promptly on freezing up. Most significantly, these bacteria contain the genetic codes of al…

Intelligient Design

Comets leave in their wake trails of rocky material, the source of annual meteor showers on Earth. As the rocks burn up in Earth's atmosphere some wonder if the intense heat destroy any organics within the rocks? Apparently not, says NASA astro-biologist Peter Jenniskens. He and his team of researchers observed the Leonids meteor shower from aboard aircraft. Jenniskens has announced that much of the organic material in the rocks appears to have survived entry into the Earth's atmosphere. Life's components have come from space on Earth just as they have done so on other planets. The cosmos shares the same gene pool. Therefore it is not surprising that some species are similar even on planets light years away from each other. However since the possible varieties, especially of plant and animal life is vast, different species show up on different planets. Nevertheless, since the so-called intelligent species in the universe are limited, there is greater likelihood of finding …

Human Genes

The human genome contains not 100,000 genes but around 25,000 genes, little less than double the 13,601 genes of a fruit fly and barely little more than the roundworm’s 19,098. Moreover, there is hardly any uniqueness to the human genes. They are akin to 99 percent of the chimpanzees, and 70 percent of the mouse. Human genes, with the same functions, were found to be identical to genes of other vertebrates, as well as invertebrates, plants, fungi, even yeast. The findings confirm that there is one source of DNA for all life on Earth. It enables scientists to trace how more complex organisms evolved, genetically, from simpler ones, adopting at each stage a few more genes contributed by viruses culminating with Homo sapiens. The genomic loci and length of certain types of small repetitive sequences are highly variable from person to person, which is the basis of DNA fingerprinting and DNA paternity testing technologies.

Scientists have found that the human genome contains 223 genes t…

Viral Action

A viral protein, known as syncytin, is hugely expressed in placental tissue – especially at the beginning of embryonic development – and is giving signs of bearing an essential role in placental architecture. Placental evolution, and indeed all evolution, results from viral actions. The virus in question is in fact a retrovirus known as human endogenous retrovirus, HERV-W. The human genome – as indeed many other eukaryotic genomes – is retroviral and viral genes added in stages to those of an amoeba. The retroviral protein syncytin is an example of how a retroviral product has been integrated in the host’s genome. The placenta is lined, on the mother’s side, by a tissue known as the syncytiotrophoblast – from where the protein’s name derives. The syncytiotrophoblast is an essential tissue for the proper development of the embryo, acting as a place of nutritional exchange between the mother and her child, as well as a center for hormone synthesis and it has a role in the fetus immunity…

Sexual Differentiation

The most primitive of multi-celled creatures may reproduce both by conjugation or fission. However those that produce by conjugation survive many more generations than others reproducing by fission simply because then genes that develop errors can be ignored and deleted. On the other hand organisms reproducing by fission cannot maintain the genetic integrity required to perpetuate more complex multi-celled creature. The most primitive of the conjugating organisms can play the role of a male or female according to convenience. With further evolution the role gets segregated into distinct male and female characteristics.

The need for gene repair is the primary reason sex evolved. A second reason for encouraging sex is that it leads to the development of societies and that is essential for evolution of different forms of life. For evolution it is necessary to infect large populations living in societies to affect a genetic change. A third reason is that in more complex life forms, nurtur…

From Single to Multiple Cells

Human and animal egg cells are astonishingly similar to those of an amoeba. They both have a nucleus, they share all the same kinds of membranes and organelles. They both divide using the same mechanism (mitosis). The difference is that once the human egg cell starts dividing, the resulting cells stick together, and eventually start 'differentiating' - i.e. becoming different kinds of cells which results in the different types of structures and organs we can see in a human. But the question is can a single celled amoeba develop into a multicelled creature? The answer is yes, and scientists have seen it happen.

The social amoebae are exceptional in their ability to alternate between unicellular and multicellular forms. The best-studied member of this group is Dictyostelium discoideum, known as Dicty to researchers, spends most of its time living alone in the soil as a single-celled amoeba. However, in a food shortage the individual cells communicate, aggregate and then develop …

From Bacteria to Amoeba

Eukaryotic cells that include humans, animals, and amoebae, contain small structures called organelles. Bacteria do not in general contain these structures. Religious persons have argued that there is no way a bacterium can evolve into even a single amoeba or human like cell. However, Research biologist Lynn Margulis has finally won acceptance for the theory that eukaryotic cells formed by symbiosis among bacterial cells. Thus early evolution takes place by symbiosis as well as viral action. It is only when more complex multi-celled life forms emerge that viral action becomes the primary mechanism for further evolution. The cells of all other living things rely on organelles. Bacteria were thought to manage with a single open space devoid of partitions Now a team led by microbiologist Roberto Docampo at the University of Illinois in Urbana say they have found the first organelles in that have a direct counterpart in higher organisms. (M. Seufferheld et al. J. Biol. Chem.; 2003). Such …

Microbes – Beginning of Life

The simplest form of life and yet the most important is bacteria. It consists of a single cell. The most important component of bacteria is its DNA. It is wrapped up like a ball of string and floats in a watery fluid contained in an outer wrapper called the cell membrane. The fluid inside the membrane called the cytoplasm is mostly water and a mix of organic chemicals such as enzymes that the cell has manufactured along with amino acids, glucose etc. At the center of the cell is the ball of DNA that carries the genetic code of the bacteria. Some bacteria have limb like structures attached to their membrane called the flagellum that help propel bacteria. Different bacteria have different number of flagellum. Some have none. The shape of different bacteria too differs. Some are shaped like an ellipse, others may be squeezed in the middle or sides etc. Human cells have the same basic features as bacterial cells along with additional advanced features. The cytoplasm of bacteria contains n…

Life Everywhere

The Milky Way is about 100,000 light-years in diameter. The universe as we know contains about a 1000 billion galaxies. From time to time large objects from space hit all planets as well as the Earth. Small objects fall to Earth quite often, we call then shooting stars or meteorites, and they are just tiny asteroids. Some are made of rock and others are lumps of iron. Comets come from deep space and are frozen lumps of rock and ice. They have cool cores of ice and it is these that bring new genetic codes to earth from the cosmos on a regular basis, just as they do to other planets. When large comets hit a planet some material splashes out to create new objects in the heaven. Some of these carry away genetic codes to the cosmos. Thus we end up with a universe that has the code of life everywhere in the cosmos, ready to spring to life with the scent of moisture.

How can you prove that the universe is filled with this code of life? One may deduce that easily from the spectrum of light ab…

The Big Bang

Humans love things that have a beginning. Therefore they have come up with the Big Bang theory of the universe on earth. The alternative theory of a universe that always was, is a bit too formidable for many to handle. However, humans know that there is infinity in space. The dimensions of space go on and on without limit in either direction so why not time? In fact, the infinity of time is just like the infinity of space. The standard Big Bang model is founded upon a faulty paradigm that is inconsistent with the empirical data. Other dissenters on your planet include Nobel laureate Dr. Hannes Alfvén, Professor Geoffrey Burbidge, Dr. Halton Arp, and the renowned British astronomer Sir Fred Hoyle, who is accredited with first coining the term "the Big Bang" during a BBC radio broadcast in 1950. These latter are on the right track. The universe has no beginning
The universe is an oscillating universe, it expands to a certain extent and then shrinks, but it doesn’t shrink all t…

The Code for Life

Some readers who do not have much interest in the science of genes can skip most of this post and move on to newer one, although it is not really difficult for the keen reader

The blue prints for all known life forms are contained within a single cell. After all, all life including human one starts from a single cell. Modern genetic science does not fully understand the workings of this single cell yet. At the core of a cell lies the genetic code that is the blue print for a life form. To gain an elementary knowledge of what this genetic code is, consider two single rungs of a ladder as shown in figure 1 with one of the four alphabets A, T, C or G sitting on the rungs. These two rungs are the only two basic elements that can now be joined up in various manners to construct the entire ladder or ladders that forms the basic code of all life forms. In the genetic code the rungs are made off a certain chemical compound and the four alphabets four different chemical compounds found in natu…

The Universe we Live in

15th of September 2006

As spoken in the voice of an Alien from a more advanced planet in a galaxy far far away:

At one time you thought that of your world as stationary and at the center of the universe. The stars were thought of as lights for the night sky. We now know that stars are similar to your sun and appear small only because of their great distance from your planet and not because of their size. Stars vary in size. Some may be a thousand times smaller than your own, whereas others may be a thousand times larger. Stars vary in color too, because they are not all equally hot. They may be red, orange, yellow, white or blue depending upon how hot they are. Some stars are younger and have come into being much more recently than your own sun. Others are older and some have even come to the end of their lifecycles. Novas and Supernovas are dying stars that have come to their end in a final grand explosion.
Different portions of the celestial sphere i.e. the sky surrounding your planet…