Listen while you read...
Just as the universe originated from a big bang, you and what makes you - your DNA is a record of the DNA of all of your ancestors going back to the start of single cell life billions of years ago.
Man did not evolve from monkeys or fishes or any other species, even though it shares most of its DNA with them. As shown in the Genealogical Tree of Humanity below, Man is just a branch from the stem that all branches like monkeys, fishes or any of the species share. Man's genes, and thus the genes of every dead and living man run right to the roots of the tree.
Man is the latest fruit on the Genealogical tree of life and because its roots go right to the start, it has in a way accumulated the DNA of bacteria, plants, fungi, fish, amphibians, insects, birds and all other species that branched off the stem forming their own unique species that have survived. It is as if our DNA was accumulating all the other DNAs of the other species.
A few million years ago, our DNA flowered and formed its own species. Humans have achieved their special status of dominating their environment because they are a collection of the best features of the other animals and play the "jack of all trades" role. With discovering fire and cooking food to grow large brains, humans discovered language and were able to discover technology. With the help of his machines, humans were able to surpass the capabilities of all other life forms and became like gods.
Each DNA in each of your cells is like a complete manual for making you grow into an adult. The human genome consists of approximately 3 billion base pairs of DNA, which are distributed across 23 chromosomes. 99.9% of the of the base pairs make a human and are the same for all humans. Only 0.1% or 3 million defines how you look and how you function at each stage of your growth. You not only inherit the physical traits of your ancestors, but also their accumulated adaptations to how they function and behave with their ever changing environment.
A few million years ago, our DNA flowered and formed its own species. Humans have achieved their special status of dominating their environment because they are a collection of the best features of the other animals and play the "jack of all trades" role. With discovering fire and cooking food to grow large brains, humans discovered language and were able to discover technology. With the help of his machines, humans were able to surpass the capabilities of all other life forms and became like gods.
Much like a hive of bees, your body is a collection of different cells interconnected in a network to work together. Each cell has the very same DNA with the instructions to when and to what kind of cell it must divide into. Depending on its specific requirements, it follows instructions coded on the DNA to make the right types of proteins at the right time so that the cell grows. This DNA is the book of your life. The book of each life started with how it started out as a virus 4 billion years ago.
In the beginning were 2 stable group of atoms with shapes that could be copied and arraigned like 0s and 1s to form a code. The code defined bigger shapes of atoms that could be arraigned much like letters to form many even more complex shapes much like words. Each word had a meaning and was arraigned to form sentences that spelled out instruction for making even bigger shapes that revealed different functionalities. We relied on chance to be copied, and we relied on random winds in our environment to be moved around. We were like cars without a motor.
Much like making parts of a motor for a car, a miraculous wind developed that caused the different stable shapes of molecules to assembled into a motor able to take energy from the sun and transform it so that it can move in its environment and search for nutrients it needed to grow. This wind was like a breath of life and the life were called chloroplast bacteria.
Another miraculous wind developed that caused molecules to assemble into a motor able to take energy from breaking apart the plants and transform it so that it can move in its environment to avoid dangers and to search for nutrients it needed to grow. This wind was like a breath of life called mitochondria bacteria.
The very first chapters of the book of life have been greatly edited and summarized so that only the remnants remain describing how it started out to be a virus 4 billion years ago. It was copied and re-written and re edited many times. I eventually found a mitochondria. We worked so well together, hepling each other that we survived to evolve. With each evolution, the book of life had a new edition. With each edition, new chapters describing new complexities and new functions and features were added, while the older chapters were reduced to summaries.
One of my favourite chapters in my book of life is the chapter of sex where I make special cells that contain only half of my book of life. It has to be mixed with half the book of another life to make a complete book of a new life. This new life can continue if it survives and propagates. In this way, traces of my contribution survives, just like the traces of the virus I originated from survived in my book.
All cells from plants and animals contain DNA, the instruction book for life.
Animals are mostly a blob of different proteins. Proteins are chains of amino acids, which are carbon chains with N tails and COOH heads. Protein forms bones and muscles and blood and all our hormones and enzymes. The DNA tells the cells how to make this protein.
Each DNA in each of your cells is like a complete manual for making you grow into an adult. The human genome consists of approximately 3 billion base pairs of DNA, which are distributed across 23 chromosomes. 99.9% of the of the base pairs make a human and are the same for all humans. Only 0.1% or 3 million defines how you look and how you function at each stage of your growth. You not only inherit the physical traits of your ancestors, but also their accumulated adaptations to how they function and behave with their ever changing environment.
The DNA specifies what each cell will be, whether muscle, bone, skin or hair or any of the many organs, by time marking the DNA to produce the appropriate proteins at the appropriate time. To make proteins, the DNA unzips at the appropriate parts of the DNA. In this way the cells know what type of cells to become and what proteins need to be made depending on the environment.
As an example, the gene sequence:
..ATCGGCTAACCCCGGATTACGGGGAAATGGGCCCATCGGGCTAA CCCCCCCCGG.....
might read as follows.
“....Hello cell # 15,603, you are a bone cell. The coding to make the proteins you need right now are coded as follows..............”
Your DNA, which is identical in each of your cells has the entire code to make a clone of you. Your body is mostly protein but only 2% of our DNA code for protein. Non coding DNA called "junk DNA" code any traits that you have learned from your environment so that they can be passed on to your children. It also turns on and turns off protein making genes ensuring that the right proteins get made to keep you growing healthy and to protect you from inner and external stresses. It can be compared to the operating system of a computer.
Our DNA comes packaged in 23 pairs called chromosomes. One of the pairs comes from the mother, the other pair comes from the father. Each chromosome of a matching pair is structurally similar to each other and has the same genetic material arranged in the same order and physical location. The genetic material in each chromosome comprises a series of discrete genes that influence all our traits, from the color of our skin, hair and eyes to our strengths and weaknesses.
Like a collection of instruction manuals for how to build and maintain a human, humans have 46 chromosomes, half from the mother and half from the father. A person has all genes from each parent but only expresses one of them, called the dominant gene. The dominant genes can either come from the father or the mother. The child is a random blend or mixture of his parent’s genes. When the mother provides more dominant genes than the father, than the child is more like the mother than like the father. And when both genes provided by the parents are recessive, than the child is more like his grandparents in that particular trait expressed by the gene.
DNA is made from 2 strands of 4 molecules A, T, C and G.
Because A always bonds with T and C always bonds with G, DNA can replicate by unzipping into two strands. Once unzipped, opposing negative strands are formed from the available A, T, C and G molecules in the area. In this way a double strand can replicate into 2 identical double strands.
The ATCG sequence making the DNA is the same in each cell of a living being. This sequence forms the genes that are turned ON or OFF depending on the needs of the cell. This decides what type of cell to grow and the proteins that need to be produced at the right time and the right place and at the right environmental conditions.
Of the 2 copies of every gene, 1 from the mother and 1 from the father, one of them is marked DOMINANT and the other is RECESSIVE. Dominant genes mask the expression of the recessive ones. As long as a plant inherits a dominant gene for tallness (T) from either parent; then it will be tall. It will be only short if it inherits a recessive tallness gene (t) from both parents.
The genetic code is the set of rules by which information encoded in DNA is translated by living cells into proteins. A sequence of 3 molecules is called a codon. There are 64 possible combinations of codons to code for 20 amino acids. There is a codon as a marker to start sequencing, codons for all of the 20 amino acids and 3 codons to signal the end. This redundancy of codes ensures a resilient and accurate copying system.
ATG is the "START" codon and TAA, TGA or TAG are "STOP" codons. The 20 amino acids are named using the letters of the alphabet.
For example, if the protein has a sequence of amino acids FKHY, then that protein can be made from the sequence on the DNA.
Cells divide to make new cells for growth or replacement. Each time a cell divides, the DNA also divides. The strand unzips into 2 half strands. The 2 half strands attract from the environment the necessary molecules to become 2 full strands. The "Ts" attract "As", the "As" attract "Ts", the "Cs" attract "Gs" and the "Gs" attract "Cs".
For an adult to reproduce without forming an exact clone, it must make special cells called gamete cells, or sex cells that couple with sex cells from another adult. To make a gamete cell, you take a normal cell with the father’s DNA labeled "F" and the mother`s DNA labeled "M" and you have them do a dance called "meiosis" where the strands of DNA are replicated, coupled and shuffled.
The strands exchange genes with each other like they were making love, resulting in 4 unique strands labeled "1", "2", "3" and "4" which form 4 gamete cells all with unique DNA, but with only half of the DNA of a normal cell.
Fortunately sex chromosomes do not cross over and get shuffled and recombined so the child's sexual traits are not a blend of his parents. The child is either entirely male with a penis or entirely female with a vagina. This is determined by the father alone. The father, being male, has his sex chromosome pair as "Xy". Males have one of their sex chromosomes shortened leaving them with one long “X” and one short “y”.
Females have 2 long sex chromosomes “XX” because they need the extra genes needed to develop breasts and a womb needed to give birth.
While females have only an “X” to deal out as far as sex, males can deal out either an “X” or a “y”. If the father deals out his “X” from his genetic stack of cards, than the child will be a girl (XX). If he deals out a “y”, than his child will be a boy (Xy).
Mothers are born with about 1 million eggs, each of them different and enough to last her a life- time. They are held in 2 ovaries that release about 1,000 eggs every month at menstruation along with hormones called estrogen. Usually only one of the 1,000 eggs released anchors in the womb to be hopefully fertilized by semen containing sperms of a man. When a woman runs out of eggs at about age 50, she gets hot and cold flashes called menopause.
Fathers produce millions of tiny mobile sperm from their 2 testicles and ejaculate them with stimulation on demand or simulation in a dream. Males can ejaculate semen filled with swimming sperm from puberty when they get hot flashes and discover what their penis is for, until they forget what it's for or die. Each ejaculation releases up to 3,000 million sperm, all different and all looking to hook up with an egg to penetrate.
Egg cells only allow one sperm inside despite that millions try. Once penetrated, the egg is fertilized and starts to divide. The mitochondria that has its own DNA and that powers all cells is right at the tail of the sperm. Because the tail of the sperm detaches before the sperm enters the egg to fertilize it, the father`s mitochondria is not passed down genetically. Once the egg is fertilized, it doubles with every division. Sometimes a fertilized egg divides into 2 embryos producing identical twins that are in fact clones.
All subsequent cells that divide from the fertilized egg contain the same complete DNA, no matter what kind of cells they end up to be to form the fetus. When the cell divides, it follows a dance called "mitosis".
The double chain, one from the father labeled "F" and the other from the mother labeled "M" separate, duplicate, and couple. The 2 couples are pulled to opposite sides of the cell which stretches apart into 2 separate cells each with the same DNA. Each subsequent cell, whether muscle or bone has the identical DNA.
The growth of an individual organism starts when the special sex cells called gamete cells, each with only half of the DNA of normal cells, are formed and are coupled. In plants, gamete cells are called spores, and in animals they are called sperms and eggs.
A single chain of DNA from the father's sperm is a random mixture of genes from his father and his mother. A single chain of DNA from the mother's egg is a random mixture of genes from her father and her mother. When an egg is fertilized by a sperm, it starts to divide an embryo that develops into a fetus. It takes 40 weeks from conception for the embryo to be born.
From 4 weeks to 8 weeks
6 weeks
9 weeks
Here is how it all starts......
and 4 weeks later...
8 weeks
12 weeks, wow fingers...
16 weeks
20 weeks
It was just too crowded in there... I just had to get out.
32 weeks
36 weeks, its getting crowded in here. Get me out of here...
32 weeks
40 weeks
The size of a developed human egg cell is about 100 micrometers in diameter, about the size of a period at the end of this sentence. The largest egg comes from a whale and it measures 35cm in diameter. The DNA from one of the 100 trillion cells of a human body has about 3,000 million A, T, C, G molecules and if stretched out would be about 3 meters long.
With the help of computers and machines able to see DNA, chemists have been able to decipher the genetic code and open and leaf thru and read a few pages of the genome collection. As computers evolve, man will be able to not only read and understand the entire library, but to write it.
Then man will play the game of god and create a new life form using the best genes of all plants and animals.
...every sperm is sacred.... if it gets wasted, God gets irate.
THE END
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