10.2 Eukaryotic chromosomes

Question 1

how many chromosomes do most eukaryotes have in their somatic cells

Answer 1

10-50 chromosomes

Question 2

how many genes does each chromosome contain

Answer 2

hundreds or thousands

Question 3

missing a chromosome

Answer 3

monosomy

Question 4

having an extra copy of any one chromosome

Answer 4

trisomy

Question 5

the particular array of chromosomes an individual organism possesses

Answer 5

karyotype

Question 6

chromosomes vary in

Answer 6

size, staining properties, location of centromere and relative length of the 2 arms

Question 7

one complete set of chromosomes

Answer 7

haploid

Question 8

2 complete sets of chromosomes

Answer 8

diploid

Question 9

what is the human haploid and diploid number

Answer 9

23 haploids and 46 diploids

Question 10

maternal and paternal chromosomes are 1 pair of the same kind of chromosomes in a diploid and are referred to as

Answer 10

homologous

Question 11

chromosomes are composed of

Answer 11

chromatin

Question 12

a complex of DNA and protein (40% DNA and 60% Protein)

Answer 12

chromatin

Question 13

how are chromosomes associated with RNA

Answer 13

they are the sites of RNA synthesis

Question 14

how many DNA molecules does 1 chromosome have

Answer 14

1

Question 15

how many nucleotides does each chromosome contain

Answer 15

140 million

Question 16

the non active domain of chromatin in a nondividing nucleus

Answer 16

heterochromatin

Question 17

the active domain of chromatin in a nondividing nucleus

Answer 17

euchromatin

Question 18

nucleosomes are composed of

Answer 18

DNA and histone proteins

Question 19

the __ charged histones are attracted to the __ charged DNA phosphate groups

Answer 19

positively, negatively

Question 20

what are the 4 primary histones

Answer 20

H2A, H2B, H3 and H4

Question 21

How is a nucleosome formed

Answer 21

DNA duplex coils around 8 histone proteins every 200 nucleotides

Question 22

nucleosomes can further coil into ___ which leads to a fiber __ nm in diameter

Answer 22

solenoids, 30

Question 23

further condenses solenoids

Answer 23

radial looping

Question 24

radial looping is aided by

Answer 24

condensin proteins

Question 25

2 SMC proteins that use energy from ATP hydrolysis to cause DNA looping and constrain these loops

Answer 25

condensin proteins

Question 26

how many DNA molecules is each chromosome composed of prior to replication

Answer 26

a single DNA molecule

Question 27

After replication sister chromatids are held together at their

Answer 27

centromere by cohesin proteins

Question 28

why are the products of replication being held together critical to division

Answer 28

it ensures that each daughter cell gets one copy of each chromosome