|The nucleus is
the control center of a cell because it controls all the
activities of the cell.
the nucleus of a human cell are 46 chromosome The chromosomes
are made of DNA. We can compare a chromosome to a ball
of yarn. The ball itself is the chromosome and the yarn
is the DNA.
contain genes. Genes are segments of Deoxyribonucleic
Acid (DNA) that code for the proteins in your body. Your
body is made of proteins. For example, there is a DNA
code for the protein
is made of keratin. The cartilage in your body is composed
of fibrous protein called collagen.
DNA is made of four nitrogen bases, adenine (A), thymine (T), cytosine (C) and guanine (G). Adenine always pairs with Thymine and Guanine always pairs with cytosine.The way you look is determined by proteins.The proteins that you are made from are determined by the sequence of DNA in the nucleus.
1953, James Watson and Francis Crick discovered the true
shape of DNA. The shape of DNA is called a double helix,
which looks like a twisted ladder. The sides of
are made of sugar and phosphate molecules. The
sugar is deoxyribose.
is directly attached to the nitrogen bases.
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life to continue, new cells need to be produced. For this to
happen, DNA needs to
make a copy of itself to make new cells. The new cells need
to have the correct information. Then the cell can divide and
the new cell will have an exact copy of the original DNA. When
DNA makes a copy of itself it is called DNA Replication. The
DNA ladder are bonded by hydrogen bonds. Those bonds break
and . . . .
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you remember which nitrogen bases pair up together?
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how a DNA model
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