DNA / RNA and Protein Synthesis Chapter 10

DNA DNA - is the code of life. It is the blue print of how organisms are made. it is made up of nitrogen based pairs that fit together like puzzle pieces it also has a backbone made of sugar and phosphate

DNA - double helix

DNA spiral molecule like a stair case called a double helix because it has two sides twisted together found in the nucleus of the cell in it’s chromosomes

Nucleotides / DNA Stair case Sugar backbone Nucleotide pairs

DNA Adenine – (A) is one of the nitrogen bases and pairs with Thymine (T) Guanine – (G) is another base and pairs with Cytosine (C) (A) and (G) are purines and (T) and (C) are pyrimidines

A pairs with T C pairs with G

DNA Replication – is when cells make more DNA to replace the damaged or old DNA or when a cell divides. (interphase / prophase of mitosis) DNA unzips and then a replicating piece is made. DNA is copied (fixes DNA)

DNA Crossing over – during replication often recombination of genes takes place this is called crossing over. The alleles from the two chromatids mix causing more variation in traits. (sometimes this can cause health defects as well) traits that are close to one another stay together (eye color and hair color)

DNA Sex linkage – traits that are directly hooked to the (Y) or (X) chromosomes for sex travel with that chromatid. (female (XX) baldness or (YX) male color blindness

DNA Karyotype – picture of the organisms chromosomes Genome – is the sequence of the entire DNA in an organism, this is what makes you unique.

DNA Nondisjunction – when the chromatids do not separate completely during meiosis, resulting in an extra piece of or less of a full chromatid. (Trisomy #21) Polyploidy – when there are extra sets of chromosomes. Happens often in plants.