Genomes Flashcards
T/F. Prokaryotic genome size varies according to biological complexity
True generally, prokaryotes accumulate more genes the more diverse their environment is, and tend to be smaller in a niche env
What are 5 notable features of the E coli genome?
No introns, 11% intergenic DNA, little repetitive DNA, one replication origin, and supercoiled
What is an operon
A unit of genes, often involved in the same pathway, that are transcribed together
What are three ways bacteria can horizontally transfer DNA?
Transformation, transduction and conjugation
What are 5 notable features of eukaryotic organellar DNA (specifically mito)?
10 genomes per mito, 8k genomes per cell, different genetic code, 37 genes and all proteins are part of the ETC
What are 5 notable features of nuclear genomes?
DNA molecules always linear, chromosome number varies, DNA is packaged, discontinuous genes, and gene density varies greatly
How do repetitive DNA stretches come about?
Recombination or replication slippage
Three types of repetitive DNA?
Satellite DNA repeats - centromeric, minisatellites (10-60bp) - telomeric, Microsatellites (2-6bp) - CODIS loci
What are 4 classes of transposable elements?
SINE, LINE, LTR retroelements, DNA transposons
What are some types of noncoding RNAs and their function? (5)
rRNA, snRNAs (splicing), snoRNAs (chemical mod of rRNA), siRNA/miRNA (RNA interference), piRNAs (retrotransposon silencing)
what percent of the human genome is under functional constraint?
8-15%
T/F. Regions of the nucleus are preferentially occupied by particular chromosomes
True
What are TADs
topologically associated domains, conserved across cell types and related species, they’re likely functional domains and contain genes with similar expression pattern
T/F. Genes can be organized on chromosomes according to developmental pathways
True
What delimits TADs in order to maintain their independence?
Insulator elements
