Cloning (Lesson 2)
taught by: by Juraj Kraljik (Croatia)
DNA
DNA stand for deoxyribonucleic acid.
It is molecule that is inside the structure of a chromosome. Chromosome is in the nucleus of every living cell.
DNA was discovered in the 19th century. It's duty is to control the daily operation of a cell. DNA is also responsible for the physical characteristics of all living organisms.
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A Human Cell
Do you know that there are 100 trillion cells in your body? 100 trillion! Can you write down this number?
But red blood cells are not included in this number!
All our genetic information is in these cells. We are all built from them!
There are 3 billion pairs in that information. They are subunits of DNA.
A Chromosome
There are 46 chromosomes in our body. Each of them has DNA. Our heredity depends on DNA in these chromosomes.They make us unique because they contain many individual genes.
The Cell Nucleus
Our DNA has 23 pairs of chromosomes inside the cell nucleus. Each of our parents gives us one chromosome.
A Gene
Gene is a segment of DNA.
It has the formula for making molecule. These molecule are usually protein.
There are 4 chemical parts of DNA. They are:
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A – adenine
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T – thymine
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G – guanine
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C – cytosine
It's interesting that they can't fit together in pairs with any of these chemical parts of DNA.
Adenine can fit together only with thymine. Guanine is possible to fit together only with cytosine.
A Protein
Proteins are made of amino acids. They help us to grow and give us energy. That's why we should eat more fish and drink more milk.
Proteins are great workers. They are very important for all our organs and body's chemical activities.
These is the basic knowledge about this mysterious topic.
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