basic info (DNA) Flashcards
What is DNA?
DNA is a molecule that contains all the instructions for making new cells or organisms
where is DNA stored?
in the nucleus of a cell.
what does DNA look like?
DNA has two strand which wrapped around each other. which is called a double helix.
what is DNA made up of?
DNA is made up of nucleotides.
what are Nucleotides made up of.
nucleotides have 3 parts:
Sugar, a Phosphate and Nitrogen bases.
the phosphate and sugar make up the “backbone” of the structure.
what are the nitrogen bases?
adenine (A), Thymine (T), guanine (G), and Cytosine (C.)
which nitrogen bases pair with each other.
Adenine (A) always pairs with Thymine (T)
Cytosine (C ) always pairs with Guanine (G)
what is name for the rule which determines what nitrogen bases pairs which what base?
Chargaff’s rule
what are the two kinds of bases in DNA?
Pyrimidines are single ring bases
Purines are double ring bases
Thymine and cytosine each have one ring of carbon and nitrogen atoms. (pyrimidines)
Adenine and guanine each have two rings of carbon and nitrogen atoms. (purines)
what is a gene?
A gene is a segment of DNA that codes for a protein or a trait.
how does mutation happen?
a mutation is a mistake in DNA replication. it can be either good or bad.
how are bases attracted to each other?
The bases attract each other because of hydrogen bonds
are hydrogen bonds strong?
Hydrogen bonds are weak but there are millions and millions of them in a single molecule. which makes that molecule strong.
how many bonds do each nitrogen bases have?
Cytosine and guanine bond they have 3 bonds
Adenine and thymine bond they have 2 bonds
what are the two forms of DNA?
Ladder form - Untwisted form
Double helix - Twisted form
