Meiosis

Question 1

C Phase

Answer 1

cytokinesis

*cytoplasm divides creating 2 daughter cells

Question 2

Mitosis Metaphase

Answer 2

• chromosomes attach to microtubule

- centromeres align along the equatorial plane/plate

Question 3

Mitosis Prophase

Answer 3

• nuclear envelope begins to disintegrate
• centrioles migrate to opposite poles of cell
• centrioles form microtubules (spindle)
• microtubules grow until attached to kinetochore

Question 4

Mitosis Anaphase

Answer 4

• sister chromatids separate
• microtubules are dismantled
• pulls chromatids toward pole

Question 5

M Phase

Answer 5

• mitosis

- microtubular apparatus binds to chromosomes and moves them apart

Question 6

S Phase

Answer 6

• DNA replication occurs
• 46 chromosomes become 92
  S= synthesis

Question 7

G1 Phase

Answer 7

• primary growth phase
• majority of cell life
  G= growth

Question 8

G2 Phase

Answer 8

• preparation for cell division
• replication of mitochondria
• synthesis of microtubules

Question 9

Meiosis II

Answer 9

separates the homologues into sister chromatids

Question 10

Meiosis Prophase II

Answer 10

new spindle forms to attach to chromosome clusters

Question 11

Meiosis Metaphase II

Answer 11

sister chromatids move to opposite poles

Question 12

Meiosis Telophase II

Answer 12

nuclear envelope is reformed around each of the four sets of daughter chromosomes

Question 13

Meiosis Telophase I

Answer 13

chromosomes gather at their respective poles to form two chromosome clusters

Question 14

Meiosis Anaphase I

Answer 14

chromosome pairs separate and individual homologues move to each pole

Question 15

Meiosis Metaphase I

Answer 15

• orientation of homologous chromosome pairing is a matter of chance
• independent assortment

Question 16

Crossing Over

Answer 16

sections of chromosomes are swapped creating hybrid chromosomes
*look up image

Question 17

Meiosis Prophase I

Answer 17

• homologous chromosomes pair up

- crossing over occurs between two NONSISTER chromatids

Question 18

Meiosis I

Answer 18

• separates homologues in the homologous pair

- DNA is replicated

Question 19

Homologues replicate forming ________.

Answer 19

sister chromatids

Question 20

Centromere Location Chart

Answer 20

look up image

Question 21

Karyotype

Answer 21

arrangement of chromosomes

Question 22

Independent Assortment

Answer 22

each possible orientation of which homologue faces which cellular pole could have a different outcome of parental chromosomes

Question 23

Reduction Division

Answer 23

• meiosis

- 1 diploid becomes 4 haploids

Question 24

Chromosomes are made of ____.

Answer 24

chromatids

Question 25

Animal Cytokinesis

Answer 25

- actin filaments contract to form a cleavage furrow

Question 26

Purpose of Chromosomes

Answer 26

save space | organization

Question 27

Nucleosomes coil together to form _____.

Answer 27

chromosomes

Question 28

Histones

Answer 28

- proteins that DNA wraps around | - positive charge

Question 29

Nucleosome

Answer 29

8 histones grouped together

Question 30

Most Eukaryotes have _____ chromosomes

Answer 30

10-50

Question 31

Mitosis

Answer 31

AKA: somatic cells NON reproductive cells identical!

Question 32

3 Mechanisms for Variety

Answer 32

1. independent assortment 2. crossing over 3. random fertilization

Question 33

Condensation

Answer 33

in S phase of interphase, chromosomes begin to wind up tightly

Question 34

3 Phases of Mitosis Interphase

Answer 34

1. G1 2. S 3. G2

Question 35

3 Phases of Mitosis

Answer 35

1. interphase 2. mitosis 3. cytokinesis

Question 36

Plant Cytokinesis

Answer 36

- new cell wall is laid to divide daughter cell | - cell walls grow at angles to mitotic spindle called cell plate

Question 37

G1 Checkpoint

Answer 37

- some cells never pass this point | - makes decision if cell enters S phase

Question 38

Mitosis Telophase

Answer 38

- spindle is dismantled - nuclear envelope reforms - chromosomes begin to uncondense

Question 39

Meiosis

Answer 39

AKA: germ cells sex cells NOT IDENTICAL

Question 40

G2 Checkpoint

Answer 40

should cell enter mitosis

Question 41

Cancer

Answer 41

- growth disorder of cells - cells grow uncontrollably - growing cluster of cells= tumor

Question 42

Simple Reproductive Cycle

Answer 42

1. Replication * DNA copied 2. Binary Fission * cell splits into 2 daughter cells

Question 43

Chromosome Number

Answer 43

- varies among organisms | - nothing to do with complexity of organism

Question 44

Malignant Tumor

Answer 44

- not encapsulated | - cells spread to other areas of the body (metastases)

Question 45

Binary Fission Steps

Answer 45

1. when cell reaches appropriate size, cell splits into 2 equal halves 2. new plasma membrane and cell wall are added between 2 DNA strands 3. cell constricts into 2 daughter cells

Question 46

M Checkpoint

Answer 46

- occurs during metaphase | - triggers exit of M phase and start of G1 phase

Question 47

Benign Tumor

Answer 47

- surrounded by healthy layer of cells | - does not spread

Question 48

After meiosis I, a brief ____ occurs.

Answer 48

interphase

Question 49

Humans have __ chromosomes.

Answer 49

46 (23 pairs)

Question 50

Homologous Chromosomes

Answer 50

AKA: homologues, homologous pair - same traits, but information varies - diploid (2n)

Question 51

Centromere

Answer 51

joins sister chromatids together

Question 52

Gamete

Answer 52

- reproductive cells (sperm and egg) - contain half of chromosomes found in somatic cells - haploid (n)

Question 53

Zygote

Answer 53

gametes joined together (fertilized egg) | *has two complete copies of each chromosome

Question 54

Prokaryote Replication Steps

Answer 54

1. unzipping of double stranded DNA at the origin of replication 2. new double helix formed 3. cell has 2 complete copies of DNA