Ch. 10 Flashcards
(21 cards)
Chromosomes are complexes of _____ and _______
DNA and proteins
Each chromosome typically contains a ______ linear molecule of DNA
Single
What are the regions of chromosomal sites necessary to initiate DNA replication? Eukaryotes may have many.
Origins of replication
What are the regions that play a role in segregation of chromosomes?
Centromeres
What are the specialized regions at the ends of chromosomes that are important for replication and stability?
Telomeres
What is the difference in the size of organisms genomes due to?
The accumulation of repetitive DNA sequences
Unique or non-repetitive sequences includes ______ genes and _____ regions
protein encoding, intergenic
Moderately repetitive sequences include genes for ____ and ____
rRNA, histones
Moderately repetitive genes regulate gene ____ and _____
Expression and translation
A repeating structural unit within eukaryotic chromatin is the _____
nucleosome
Nucleosomes are composed of what?
Double stranded segment of DNA wrapped around an octamer of histone proteins
What are the four core histones?
H2A, H2B, H3, H4
What is the linker hsitone
H1
H1 is also responsible for _____
compacting
SMC proteins can also compact histones by forming a ______
Loop/dimer
What compact chromatin has tightly compacted regions of chromosomes and loop domains and the transcription is inactive
Heterochromatin
What chromatin had less condensed regions of chromosomes, active transcription, and loop forms?
Euchromatin
Constitutive heterochromatin has _____ inactive transcription
permanently
Facultative heterochromatin has regions that can ______
interconvert
What does condensin do to promote the formation of metaphase chromosomes?
Condense chromosomes
What does cohesin do to promote the formation of metaphase chromosomes?
Aligns sister chromatids
