Genetic material Flashcards
Rank chromatin, nucleosome, chromosome, DNA in increasing order of complexity
DNA < Nucleosome < Chromatin < Chromosome
Nucleosome is?
Fundamental unit of chromatin
Structure of DNA when it is wrapped around a histone
Packed in euchromatin and heterochromatin
Packing of Euchromatin?
Loose - can read info
Note: EU means real, so it’s the real deal that is used for gene expression
types of bonds in DNA (3)
- Phosphodiester bonds
- Hydrogen bonds
- Glycoside bonds - between sugar and base
Nucleobase?
Nitrogenous base
A, T, G, C in DNA
Nucleoside?
Nucleobase + Sugar
Nucleotide?
Nucleobase + Sugar + Phosphate
Coding strand? Template strand? (Remember to know how to identify coding and template)
Coding: 5’ to 3’
Template: 3’ to 5’ : is read, (read up)
Polarity means - free OH
What is tRNA made of?
RNA - AUGC
Purines? Pyrimidines?
Pure as gold
Purines: A, G
double ringed
Start codon
AUG
Stop codons
UAG, UAA, UGA
Steps in translation and transcription
initiation, elongation, termination
Introns and exons?
Introns - intervening, spliced w the splicesome, exon is expressed
- Nucleolus: makes ribosomes
- chromatin : carries genetic info
- Nuclear envelope - double membrane, has pores for transport
- Nucleolus: makes ribosomes
- chromatin : carries genetic info
- Nuclear envelope - double membrane, has pores for transport
Acetylation is? In which type of chromatin? Why?
What: acetyl groups modify chromatin
In: Euchromatin
Why: loose packing of nucleosomes for gene expression
-enhances unwrapping of DNA to open for transcription
Methylation is? Where? Why?
What: Modified chromatin with methyl groups
Where: heterochromatin
Why: makes nucleosomes tightly packed, gene not expressed
process in which 3’ -> 5’ strand is turned into -> mRNA, which strand? bases involved?
- 3’- 5’ is template so
-Transcription - DNA: ATGC
-mRNA: AUGC
splicing occurs in?
transcription
What is complimentary base pairing?
A=T
G=_C
Purines bond with pyrimidines
Structural differences in RNA?
- Uracil is more reactive
-Ribose instead of deoxyribose, has 2’ OH
-Single stranded
Codons?
3 nitrogenous bases
Central dogma?
DNA -> mRNA -> Protein
Transcription Process?
- Stimulus triggers and transcription factors (positive indicate to start) Initiation
- Initiation: RNA polymerase binds to promotor region(TATA box which make it easy to split it apart), splits DNA into 2 strands
- Elongation: RNA primers attach, codons similar to coding except U instead of T
4.Termination: elongation till terminator region (factors)
TATA box?
initiation
splicesome function?
cuts introns out and makes final mRNA that is translated
Ribosome made of?
rRNA and proteins
tRNA components?
- anticodon (complimentary to codon)
- amino acid
