Chapter 4a: Chromosomal Basis of Heredity

Question 1

• single chromosome plus plasmids

Answer 1

prokaryotes

Question 2

copies its chromosome and divides immediately afterward

Answer 2

prokaryotes

Question 3

circular chromosome

Answer 3

prokaryotes

Question 4

Chromosome made only of DNA

Answer 4

prokaryotes

Question 5

chromosome found in the cytoplasm

Answer 5

prokaryotes

Question 6

have many chromosomes

Answer 6

eukaryotes

Question 7

have linear chromosomes

Answer 7

eukaryotes

Question 8

chromosomes made of chromatin, a nucleoprotein (DNA coiled around histone proteins)

Answer 8

eukaryotes

Question 9

chromosomes found in a nucleus

Answer 9

eukaryotes

Question 10

copies chromosomes, then the cell grows, then goes through mitosis to organize chromosomes in two equal groups

Answer 10

eukaryotes

Question 11

chromosomes condensed and visible during cell division

Answer 11

eukaryotes

Question 12

Chromosomes of eukaryotes: At the beginning of mitosis they can be seen to consist of two threads (__) joined by a __

Answer 12

• sister chromatids
• centromere

Question 13

The sister chromatids are __ copies

Answer 13

identical

Question 14

Parts of eukaryotic chromosome

Answer 14

• p arm (petite)
• centromere
• q arm
• telomere

Question 15

__ is a specific region of the eukaryotic chromosome where the __ (the complex of DNA and proteins to which the spindle fibers) attach and pull the chromosomes during both mitosis and meiosis

Answer 15

• centromere
• kinetochore

Question 16

types of chromosomes based on centromeric position

Answer 16

• metacentric
• submetacentric
• acrocentric
• telocentric

Question 17

centromere is median

Answer 17

metacentric

Question 18

centromere is submedian

Answer 18

Submetacentric

Question 19

centromere is subterminal

Answer 19

acrocentric

Question 20

centromere is terminal

Answer 20

telocentric

Question 21

protects the end of the chromosome from deterioration

Answer 21

telomere

Question 22

length shortens with age

Answer 22

telomere

Question 23

GT rich repetitive sequences at the ends of the chromosomes

Answer 23

telomere

Question 24

daughter chromatids are bound at the __

Answer 24

centromere

Question 25

where microtubules attach during mitosis (more later)

Answer 25

kinetochore

Question 26

telomeres at the ends of chromosome are __ sequence (__ - __ times), maintained by __

Answer 26

- TTAGGG - 500-3000 - telomerase

Question 27

__(phase): Multicellular organisms __ their chromosomes before cell division : They must __ to a mature size. : The nucleus divides, distributing the chromosomes into two equal groups (__)

Answer 27

- interphase - copy - grow - mitosis

Question 28

The cytoplasm then divides (__) each part taking a nucleus.

Answer 28

cytokinesis

Question 29

The Cell Cycle

Answer 29

Interphase: Gap 1 (G1) - Cell grows Synthesis Phase - Replication of DNA Gap 2 (G2) - cell prepares to divide Mitotic Phase (M) - cell division Gap Zero (G0) Phase - Quiescent state

Question 30

organelles and molecules required for cell division are produced. Cell prepares for mitosis.

Answer 30

Gap 2 (G2) Phase

Question 31

§ results in the production of two daughter cells from a single parent cell § The daughter cells are identical to one another and to the original parent cell.

Answer 31

mitosis

Question 32

* Results in the production of germ (sex) cells * halves the number of chromosomes * picks one chromosome from each pair at random and places them in a sex cell. This results in enormous variation amongst the sex cells.

Answer 32

meiosis

Question 33

Meiosis: chromosome number?

Answer 33

halved

Question 34

Meiosis: daughter cells?

Answer 34

four

Question 35

Meiosis: genetic variation?

Answer 35

cross over

Question 36

Stages of mitosis

Answer 36

- prophase - metaphase - anaphase - telophase - cytoknesis

Question 37

Mitosis: Chromosomes condense.

Answer 37

prophase

Question 38

Mitosis: Chromosomes align at the equator.

Answer 38

metaphase

Question 39

Mitosis: Sister chromatids separate.

Answer 39

anaphase

Question 40

Mitosis: Nuclear envelope reforms.

Answer 40

telophase

Question 41

Stage in prophase where chromosomes continue to condense and become visible.

Answer 41

leptotene or leptonema (thin thread stage)

Question 42

The process of pairing of chromosomes

Answer 42

synapsis

Question 43

Stage in prophase where crossing over occurs between homologous chromosomes.

Answer 43

Pachytene (thickening stage)

Question 44

Stage in prophase where homologous chromosomes begin to pair up and become visible as pairs.

Answer 44

zygotene (pairing stage) or zygonema

Question 45

stages of Prophase I

Answer 45

- Leptotene - Zygotene - Pachytene - Diplotene - Diakinesis

Question 46

characterized by desynapsis and chiasmata formation.

Answer 46

Diplotene (duplication stage) or diplonema

Question 47

Stage in prophase where nuclear envelope breakdown and spindle formation continue.

Answer 47

Diakinesis (moving apart stage)

Question 48

crossing over =

Answer 48

recombination

Question 49

What is the term for the site of crossing over between non-sister chromatids during meiosis?

Answer 49

chiasma

Question 50

Stage where genetic material is exchanged between homologous chromosomes?

Answer 50

prophase I

Question 51

Stage where homologous chromosomes align independently at the cell's equator?

Answer 51

metaphase I

Question 52

Stage where homologous chromosomes separate and move towards opposite poles?

Answer 52

anaphase I

Question 53

Stage where nuclear envelopes form around each set of chromosomes?

Answer 53

Telophase I

Question 54

Stage where chromosomes condense again and spindle fibers form?

Answer 54

Prophase II

Question 55

Stage where chromosomes align at the cell's equator?

Answer 55

metaphase II

Question 56

Stage where sister chromatids separate and move towards opposite poles?

Answer 56

anaphase II

Question 57

Stage where nuclear envelopes form around each set of chromatids and cytokinesis occurs?

Answer 57

telophase II