Meiosis

Question 1

gametes are formed from

Answer 1

specialized diploid cells

Question 2

______ ensures the production of haploid phase in the life cycle of sexually reproducing organisms whereas _____ restores the diploid phase

Answer 2

meiosis
fertilization

Question 3

stages of meiosis

Answer 3

meiosis I
meiosis II

Question 4

how many times does dna replicate in meiosis

Answer 4

once

Question 5

how many cells are formed at the end of meiosis? what is their chromosomal state

Answer 5

four
haploid

Question 6

stages of meiosis I

Answer 6

prophase I
metaphase I
anaphase I
telophase I
cytokinesis II

Question 7

stages of meiosis II

Answer 7

prophase II
metaphase II
anaphase II
telophase II
cytokinesis II

Question 8

which phase of the meiotic division is typically longer and more complex

Answer 8

prophase I

Question 9

stages of prophase I

Answer 9

leptotene
zygotene
pachytene
diplotene
diakinesis

Question 10

during which stage of prophase I do the chromosomes become visible under light microscope

Answer 10

leptotene

Question 11

the compaction of chromosomes continues throughout which stage of prophase I

Answer 11

leptotene

Question 12

during which stage does synapsis occur (prophase I)

Answer 12

zygotene

Question 13

what is synapsis

Answer 13

chromosomes pair together

Question 14

paired chromosomes during zygotene are called

Answer 14

homologous chromosomes

Question 15

in zygotene, the chromosome synapsis is accompanied by the formation of complex structure called

Answer 15

synaptonemal complex

Question 16

the complex formed by a pair of synapsed homologous chromosomes during zygotene is called

Answer 16

bivalent or tetrad

Question 17

bivalents or tetrads are clearly visible during which stage of prophase I

Answer 17

pachytene

Question 18

pachytene is characterized by

Answer 18

appearance of recombination nodules

Question 19

where are recombination nodules formed during pachytene

Answer 19

sites at which crossing over occurs between non-sister chromatids of the homologous chromosomes

Question 20

what is crossing over

Answer 20

exchange of genetic material between the homologous chromosomes

Question 21

enzyme involved in crossing over is called

Answer 21

recombinase

Question 22

in which stage of prophase I does the synaptonemal complex dissolve

Answer 22

diplotene

Question 23

during diplotene, after the synaptonemal complex is dissolved, do the bivalents separate from each other

Answer 23

yes except at the sites of recombination

Question 24

sites of crossover of chromosomes are called

Answer 24

chiasmata

Question 25

in oocytes of some vertebrates, how long does diplotene last

Answer 25

months or years

Question 26

terminalisation of chiasmata is seen in which stage of prophase I

Answer 26

diakinesis

Question 27

in which stage of prophase I are the chromosomes fully condensed

Answer 27

diakinesis

Question 28

during which stage of prophase I do the meiotic spindle assemble to prepare the homologous chromosomes for separation

Answer 28

diakinesis

Question 29

during which stage of prophase I does the nucleolus dissapear and the nuclear envelope disintegrate

Answer 29

diakinesis

Question 30

_______ of prophase I represents the transition to metaphase

Answer 30

diakinesis

Question 31

during which phase of meiosis I do the bivalent chromosomes align on the equatorial plate

Answer 31

metaphase I

Question 32

during which phase of meiosis I do the microtubules from the opposite poles of the spindle attach to the pair of homologous chromosomes

Answer 32

metaphase i

Question 33

during anaphase I, the _________ ________ separate while ______ _______ remain associated at their centromeres

Answer 33

homologous chromosomes sister chromatids

Question 34

during which phase of meiosis I do the nuclear membrane and nucleolus reappear

Answer 34

telophase I

Question 35

after cytokinesis I, the state of two cells is called

Answer 35

dyad of cells

Question 36

although in many cases the chromosomes do undergo some dispersion, they do not reach the extremely extended state of the ______ nucleus

Answer 36

interphase

Question 37

the stage between the two meiotic divisions is called _____ and is generally short lived

Answer 37

interkinesis

Question 38

meiosis II represents

Answer 38

mitosis

Question 39

during which phase of meiosis II does the nuclear membrane disappear and the chromosomes again become compact

Answer 39

prophase II

Question 40

during which stage of meiosis II do the chromosomes align at the equator and the microtubules from opposite poles of the spindle get attached to the kinetochores

Answer 40

metaphase II

Question 41

during which phase of meiosis II do the chromosomes simultaneous split towards the opposite poles

Answer 41

anaphase II

Question 42

during which stage of meiosis II do the two groups of chromosomes get enclosed by a nuclear membrane

Answer 42

telophase II

Question 43

after cytokinesis II, the state of four cells formed is called

Answer 43

tetrad of cells