Genetics Intro--8/25 Flashcards
DNA contains the ________; RNA contains ______
2’- Deoxyribose x=H; ribose x=OH
_________ are the monomeric units of nucleic acid DNA and RNA
Nucleotides: nitrogenous base, 5-carbon sugar, phosphate
RNA and DNA contain the purine bases ______ & _____
Adenine (A) and guanine (G)
DNA contains the pyrimidine bases ______ and ______ whereas RNA contains ______ and _____
DNA- cytosine (C) and thymine (T)
RNA- cytosine (C) and uracil (U) –>
DNA and RNA are linear sequences of nucleotides linked by _______ between the…
Phosphodiester bonds= between 3’ sugar of one nucleotide and 5’ sugar of next nucleotide
DNA is double stranded: one strand runs _______ whereas the other is antiparallel and runs _____
5’ to 3’ direction and 3’ to 5’
The two strands of DNA wrap about each other to form a _____ and are held together by ________ between bases in each strand
double helix; hydrogen bonding
Adenine H-bonds to _______
Cytosine H- bonds to _______
A-Thymine
C-Guanine
Transcription of a gene generates a _____
single stranded RNA
Three major types of RNA are:
1) messenger RNA - mRNA
2) ribosomal RNA - rRNA
3) transfer RNA- tRNA
plus various other non-coding RNAs
________is modified at both 5’ and 3’ ends. In between it contains a coding region for the synthesis of a protein
Eukaryotic mRNA
Codons within a coding region…..
Each Codon is….
…dictate the sequence of amino acids in a protein
…three nucleotides long
_________ and _______ are required for protein synthesis
rRNA and tRNA
rRNA is complexed with proteins to form ribonucleoprotein particles called _______, which bind ______ and ______ during translation.
Ribosomes; mRNA and tRNA
The tRNA contains an _____ that binds to a complementary codon on mRNA, ensuring insertion of the correct amino acid into the protein being synthesized
Anticodon
…of DNA is important for containing the DNA in the cell and regulation of gene expression–especially in eukaryotes
Packaging/condensing of DNA
DNA combines with proteins called ______ to form nucleosomes that are further condensed into wound ______
histones; chromatin
Where is the DNA in a prokaryote?
cytoplasm of cell
99% of all DNA is found in the _____ of a cell.
Nucleus, separated from rest of cell by nuclear envelope
- small amount of DNA (0.1%) found in mitochondria
Nucleotides are composed of a _____, a ______, and a _______
Base (adenine, guanine, cytosine, thymine, uracil), Sugar, and a phosphate
***MONOMERIC units of Nucleic Acid
Nucleosides lack _____
phosphates
-Think about ATP (Adenine TRIphosphate…)
DNA chains consist of _____ and _____ sugars linked by a ______ created by a _______bond
bases; deoxyribose sugars (x=H); phosphate backbone; phosphodiester bond
The creation of a phosphodiester bond produces ______ that…..
Pyrophosphate ( PPi delta G= -30 KJ) –> provides energy for reaction (favorable reaction with the release of energy)
- *catalyzed by DNA polymerase
- **DNA extends only in the 5’ to 3’ direction
Adenine-Thymine = \_\_\_\_ H-Bonds Guanine-Cytosine= \_\_\_\_\_ H-Bonds
A-T=2
G-C=3
Stacking between bases –>
Major and Minor Grooves
Major Groove allows for proteins to interact with DNA
In each base pair a purine (_____, _____) on one strand forms hydrogen bonds with a pyrimidine ( _____, _____) on the other strand.
Purine–> adenine, guanine
Pyrimidine—> thymine, cytosine
Two strands of DNA are _______
Complementary