CHAPTER SEVENTEEN: NUCLEIC ACIDS AND PROTEIN SYNTHESIS
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What are the 2 closely related types of nucleic acids? Both are _______ polymers of repeating ______ units known as ____________.
DNA and RNA unbranched; monomer; nucleotides
Is a DNA or a RNA molecule larger, and how many nucleotides might each contain?
DNA is larger- several million RNA is smaller- up to several thousand.
Each NUCLEOTIDE has 3 components- what are they?
a base, a 5-carbon sugar, and a phosphate group
The nitrogen-containing BASES in nucleic acids are derivatives of ______ or ______.
PYRIMIDINE or PURINE
In DNA, the purine bases with double rings are ________ and ___________. The pyrimidine bases with single rings are _______ and __________. RNA contains the same bases, except _______ is replaced by ________.
PURINE= adenine (A) and guanine (G) PYRIMIDINE= cytosine (C) and thymine (T) RNA- THYMINE (5-methyluracil) is replaced by URACIL (U) know what they look like on page 602
In RNA, the 5-carbon sugar is ______, which gives the letter _______ in RNA. In DNA, the 5-carbon sugar is ______, which gives the letter ______ in DNA. How is this similar/different to the sugar in RNA?
ribose deoxyribose- similar to ribose except that there is no hydroxyl group (-OH) on C2’. Deoxy means “without oxygen)
What are NUCLEOSIDES? How are they produced?
a combination of a sugar and a base produced when the nitrogen atom in a pyrimidine or a purine base forms an N-glycosidic bond to carbon 1 (C1’) of a ribose or deoxyribose sugar.
The atoms in the pentose sugars are numbered with _______ to differentiate them from the atoms in the bases.
primes Ex: 1’, 2’, 3’, 4’, 5’
What are NUCLEOTIDES?
they are nucleosides in which a phosphate group bonds to -OH on carbon 5 (C5’) of a ribose or deoxyribose sugar. The product is a phosphate ester.
The name of a NUCLEOSIDE that contains a purine ends with _________ a NUCLEOSIDE that contains a pyrimidine ends with ________.
osine idine
The names of the NUCLEOSIDES of DNA add ________ to the beginning of the names.
deoxy
The corresponding NUCLEOTIDES in RNA and DNA are named by adding ________.
-5’-monophosphate
DNA contains the bases RNA contains the bases
A G C T A G C U
What are the NUCLEIC ACIDS? The phosphate link between the sugars in adjacent nucleotides is referred to as a ________ bond. As more nucleotides are added, a backbone from that consists of alternating ____ and ____ groups. The bases, which are attached to each ____, extend out from the backbone.
Polymers of many nucleotides in which the 3’ -OH group of the sugar in one nucleotide bonds to the phosphate group on the 5’carbon atom in the sugar of the next nucleotide. PHOSPHODIESTER BOND sugar; phosphate. sugar
What is the PRIMARY STRUCTURE of a nucleic acid? What is its function?
Each nucleic acid has its own unique sequence of bases, which is knows as its PRIMARY STRUCTURE. It is this sequence of bases that carries the genetic information from one cell to the next.
In any nucleic acid, the sugar at the one end has an unriddled of free 5’-phosphate terminal end, and the sugar at the other end has a free _________ group
3’-hydroxyl group
The bases in DNA from a variety of organisms have a specific relationship: • the amount of A was equal to the amount of ____ • the amount of G was equal to the amount of _____ A is always paired 1:1 with ______ G is always paired 1:1 with ______
T C T C
DNA is a _______ helix
double
What is a COMPLEMENTARY BASE PAIR?
The pairs A and T & G and C
The function of DNA in cells and bacteria is to _______ _________ _______. What happens as cells divide?
preserve genetic information Copies of DNA are produced that transfer genetic info to the new cells.
What happens in DNA REPLICATION? What begins this process?
The strands in the parent DNA separate which allows the synthesis of complementary DNA strands. The process begins when an enzyme HELICASE catalyzes the unwinding of a portion of the double helix by breaking the HYDROGEN bonds between the complementary bases.
What does DNA POLYMERASE do?
As a complementary base pairs form, DNA POLYMERASE catalyzes the formation of phosphodiester bonds between the nucleotides.
What are DAUGHTER DNAs?
The replication process produces two new DNAs called DAUGHTER DNAs that are identical to each other and exact copies of the original parent DNA.
What is the function of RNA?
makes up most of the nucleic acid found in the cell. It is involved with transmitting the genetic info needed to operate the cell.