Chromosome Structure and DNA Sequence Organization

These flashcards cover the key concepts from the lecture on chromosome structure, DNA sequence organization, and various types of chromosomal DNA.

Bacterial and viral chromosomes are usually .

a single nucleic acid molecule largely devoid of associated proteins.

Phage λ DNA is before infection and after.

linear; circular.

Bacterial chromosomes are compacted into a .

nucleoid.

Mitochondrial DNA does not contain .

chromosomal proteins.

Chloroplast DNA is shared with DNA found in .

prokaryotes.

Polytene chromosomes are found in and of some flies.

salivary glands; guts.

Lampbrush chromosomes are thought to be extended, versions of normal meiotic chromosomes.

uncoiled.

Histones involved in nucleosomes include H2A, H2B, H3, and .

H4.

Euchromatin is and active.

less coiled; more.

Heterochromatin remains highly and is inactive.

condensed.

Pseudogenes are previously functional genes that have acquired that make them non-functional.

mutations.

The DNA of polytene chromosomes undergoes many rounds of replication without .

strand separation.

The typical diameter of a human cell nucleus is .

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Nucleosomes are condensed several times to form .

the intact chromatids.

Repetitive DNA sequences are repeated many times within .

eukaryotic chromosomes.

Highly repetitive DNA sequences contribute to the stability and of the chromosome.

integrity.

Centromeres are the primary along eukaryotic chromosomes.

constrictions.

LINEs are that encode RNAs which reverse-transcribe back to DNA.

retrotransposons.

The length of mitochondrial DNA (mtDNA) is and mostly lacks introns.

double-stranded.

Variations of eukaryotic chromosomes were revealed through studies of and chromosomes.

Polytene; Lampbrush.

Histone modifications, such as acetylation, are important for regulation.

gene.

SINEs may occur more than times in the human genome.

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Moderately repetitive DNA includes and .

minisatellites; microsatellites.

Telomeres consist of short tandem repeats that protect the of the chromosome.

ends.

DNA in cells is usually highly coiled and .

compact.

Cloning genes found in repetitive DNA includes genes that occur in multiple copies.

multi-copy.