structure of dna Flashcards
another name for nucleic acids
Polynucleotides
what are nucleic acids?
Informational macromolecules
What do nucleic acids do?
-store information and instructions
-not molecule for energy or structure
-can be replicated
-doesn’t build bones/ tissues
Monomer of nucleic acids
Nucleotides
components of nucleotides
-sugar group
-phosphate functional group
-nitrogen base
What sugar does DNA contain
Deoxyribose
What sugar does RNA contain?
Ribose (contains an extra oxygen)
Why is DNA/ RNA acids?
their phosphate group
Carbon atoms are numbered…
1-5
Phosphate group
Phosphate donates H+, resulting in a negative charge on the oxygen atom
what groups are covalently bonded to form a sugar-phosphate group?
sugar & phosphate
What does the nitrogenous base accept?
H+
4 nitrogenous bases in DNA
-Adenine (A)
-Thymine (T)
-Cytosine(C)
-Guanine (G)
what do purines consist of?
-Adenine
-Guanine
What do pyrimidines consist of?
-Thymine
-Cytosine
How do the 2 groups differ?
Pyrimidines contain one carbon ring, while Purines contain 2 carbon rings.
What does DNA being a double helix mean?
-sugar-phosphate nucleotide is repeated on second strand
-bases of each nucleotide face one another
-bases are held by hydrogen bonds
-ONLY bases of strand 1 and strand 2 connect. (not sugars)
Adenine pairs with?
Thymine
Cytosine pairs with?
Guanine
How do these bases pair?
One purine pairs with one pyrimidine
How does A bond with T?
2 hydrogen bonds
How does C bond with G
3 hydrogen bonds
What are bonds like A&T and C&G called?
Complementary base pairs
What does the code mean?
DNA is a code to produce proteins, which do the work of life.
