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Concept Map 2 Returns

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    Okay. Let's see how you did with the concept map. We know that there are two
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    copies of the human genome in every cell,
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    and cells make up tissues, which make up organs,
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    which make up the body. Cells, tissues, organs,
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    and the body together Manifest traits, which are influenced
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    by the human genome. And we learned a
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    bit about traits in lesson one. So the human
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    genome resides in the cell, and it can be divided into the nuclear genome
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    and the mitochondrial genome. The mitochondrial genome
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    has one circular chromosome per mitochondria, and there
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    are many mitochondria per cell. Now the
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    nuclear genome there's only one nucleus and
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    one nuclear genome per cell. But each
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    nuclear genome contains 23 pairs of linear chromosomes,
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    22 pairs are called the autosomes. They're
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    numbered based on their size from 1-22. One
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    being the biggest and 22 being the smallest. But one pair of the 23 pairs of
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    chromosomes are called sex chromosomes. And these determine
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    the sex of the individual. Two X chromosomes
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    will develop as a female, and then X and Y chromosome will develop as a male.
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    All chromosomes in a cell are made
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    of nucleic acid wrapped around histone proteins.
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    Now there are two different types of nucleic acid, and one of them, DNA, is
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    what makes up chromosomes. The other type,
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    RNA, we'll learn more about in lesson three.
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    DNA is composed of deoxynucleotides. There are
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    four different types of deoxynucleotides that all differ
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    in which nitrogenous base they contain. There's adenine, or A, which can base
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    pair with thymine, or T. And cytosine, or C, can base pair with guanine, or G.
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    Now DNA is double-stranded and comes in
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    a helical shape. But the double-stranded nature
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    of DNA is held together by base
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    pairs. Which are formed by the nitrogenous bases.
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    And one human genome, one copy, is made of 3 billion base pairs of DNA.
Title:
Concept Map 2 Returns
Video Language:
English
Team:
Udacity
Project:
BIO110 - Tales from the Genome
Duration:
02:16

English subtitles

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