The amount<span> of guanine </span>always equals the amount of cytosine<span>.
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Two genes, BRCA1, located on chromosome 17q21 (5,6), and BRCA2, located on 13q12-13 (7–9), have been shown to predispose to familial breast cancer.
<span>Na+, cl-, hco3-, and k+ are electrolytes. Na+ is sodium. Cl- is chloride. Hco3- is bicarbonate and k+ is potassium. Electrolytes are needed for our organs and cells to function like they should. We obtain some of these electrolytes through the food we eat, such as sodium from salt and potassium from bananas.</span>
They are capable of dividing and renewing for Long periods of time They are unspecialized and they can give rise to speacialized cell types