genetics - general Flashcards
general info on DNA, anatomy of genes
what is dna
material that comes from hereditary info
what are nucleotides made of
-PO4
- deoxyribose sugar
- N-base (A,C,T,G)
what holds the sugar-phosphate backbone together
phosphodiester bonds
what holds sugars and bases together
glyosidic bonds
what are the key characteristics of DNA
- double helix structure
- anti parallel
- complimentary
- new dna from 5’ to 3’
- a fork is half a bubble
what fn group is found at the end of the 5’ end? 3’ end?
phosphate -5’
hydroxyl - 3’
which base is unique to dna
thymine
what are the differences between dna and rna
dna: deoxyribose, thymine, large, double stranded
rna: ribose, uracil, small, single stranded
purines
adenine and guanine
- double ring
pyrimidines
thymine and cytosine
- single ring
genome
SUM of all organisms DNA
histone
proteins that organize dna into tightly coiled structures (chromosomes)
centromere
where spindle fibers attach to (non coding)
telomere
end reigons of DNA, nonsense reigon that buffers loss (non coding)
pseudogenes
never expressed due to mutations
transposons
jumping genes that move around genome by copying, cutting and pasting themselves into chromosomes
endogenous retroviruses (ERV)
extinct retroviruses that are stuck in genome
gene
specific seq or dna that codes of rna or proteins
promoter
where dna transcription begins
exons (non coding)
expressed into a.a
introns (non coding)
removed by spliceosomes before rna goes onto being transcribed
stop codon
tells ribosome where protein-coding reigon ends during dna translation
- 3 stop codons
what happens if telomere erodes
cell malfunctions and dies