Lecture 5 Reading Flashcards
Mitotic chromosomes
Highly condensed chromosomes in a dividing cell
Karyotype
The display of 46 human chromosomes at mitosis
What three types of specialized nucleotide sequences in DNA contorl replication, separation and partition into daughter cells
DNA replication origin
Centromere
Telomere
Replication origin
Nucleotide sequence
The location at which duplication of DNA begins
Centromere
Nucleotide sequence
Allows one copy of each duplicated and condensed chromosome to be pulled into a daughter cell when a cell divides
Kinetochore
Protein complex forms at centromere and attaches duplicated chromosomes to the mitotic spindle so they can be pulled apart
Telomere
The ends of a chromosome
Contain repeated nucleotide sequences that enable ends of chromosomes to be efficiently replicates
Form structures that protect the end of the chromosome from being mistaken by the cell for a broken DNA molecule that needs repair
Proteins that bind to dna to form eukaryotic chromosomes 2
Histones
Non histone chromosomal proteins
Chromatin
Complex of histone and non histone chromosomal protein with nuclear dna if eukaryotic cells
Nucleosome
Most basic level of chromosome packing
Linker DNA
Exposed dna between nucleosome core particles
Histone octamer
Forms a protein core around which the double stranded DNA is wound
Nucleosomes repeat at intervals of
About 200 nucleotide pairs
Epigeneric inheritance
A form of inheritance that is superimposed on the genetic inheritance based on DNA
Two types of chromatin
Heterochromatin - highly condensed
Euchromatin - not as condensed
Position effect
Chromosome breakage and rejoining that translocate normally euchromatic DNA into the neighborhood of heterochromatin