Molecular Structure of Chromosomes

Question 0

complete set of genetic material in an organism

Answer 0

genome

Question 1

structures within cells that contain genetic material

Answer 1

chromosome

Question 2

main function of genetic material is to _____________________________________________. what in DNA encodes this info?

Answer 2

store the info required to produce an organism

nucleotides

Question 3

found in the nucleoid

more than one copy of chromosome can be found within one bacterial cell.

Answer 3

bacterial chromosomes

Question 4

_________ is not bound by a membrane in bacterial chromosomes.

Answer 4

nucleioid

DNA is in direct contact with cytoplasm

Question 5

Bacterial chromosomal DNA is ___________ supercoiled

2 major effects:

Answer 5

negatively

1. helps compaction of the chromosomes
2. creates tension that may be released by DNA Seperation

Question 6

same molecular composition, different structural conformations

Answer 6

topoisomers

Question 7

Enzymes control supercoiling

1. DNA gyrase (DNA topoisomerase II)
   - ?
2. DNA topoisomerase I
   - ?

Answer 7

1-introduces neg supercoils using ATP

• can relax pos supercoils
• can untangle intertwined DNA mol.

2-relaxes neg supercoils

Question 8

crucial for bac. to survive(blocking the function of gyrase is a way to cure bac. diseases)

Answer 8

supercoiling

Question 9

two main classes of drugs inhibit gyrases and other bac. topoisomerases:

Answer 9

1. quinolones

2. coumarins

Question 10

eukaryotic chromosomes have one or more sets, they are __________ not circular.

• more DNA
• chromosomes are located in the _______

Answer 10

linear

nucleus

Question 11

Eukaryote Genomes:
-genomes vary in _____
-variation is not related to the complexity of the ________
-

Answer 11

size

species

Question 12

located along the entire chromosome btween the centromere and telomere regions.

Answer 12

genes

Question 13

in lower ___________ ex:yeast, genes are relatively small

and in higher___________ ex:mammals, genes are long

Answer 13

eukaryotes

Question 14

sections of genes that are translated into proteins (coding)

Answer 14

exons

Question 15

sections of genes that are NOT TRANSLATED into proteins

Answer 15

introns

Question 16

specialized seq that interact with proteins and affect transcription (synthesis of RNA)
-occur upstream of genes

Answer 16

enhancers

Question 17

refers to the # of times a particular base seq appears throughout the genome.

Answer 17

seq complexity

Question 18

3 types of seq complexity

Answer 18

unique or non-repetitive
moderately repetitive
highly repetitive

Question 19

found once or a few times in the genome

• includes structural genes as well as intergenic regions
• makes up 41% of human genome

Answer 19

unique or non repetitive seq

Question 20

found a few hundred to several thousand times

• genes for rRNA and histones
• origins of replication
• seq that regulate gene expression and translation
• transposable elements

Answer 20

moderately repetitive seq

Question 21

found tens of thousands of times to millions of times

• each copy is relatively short
• some are inter spread throughout the genome
• some are clustered together in tandem arrys-commonly found in centromeric regions

Answer 21

repetitive seq

Question 22

compaction of __________ _ involves several diff. proteins

Answer 22

linear DNA