Cell Cycle Division

Question 1

Cell Cycle Def.

Answer 1

Process by which cells divide passing their DNA onto genetically identical daughter cells

Question 2

Consequences of faults in DNA replictation

Answer 2

Chromosome Anomalies (mutation), inherited disease and cancer

Question 3

G0 in cell cycle

Answer 3

Optional non-replication phase. Differentiated cells tend to remain in this phase

Question 4

G1 Cell Cycle (10 hrs)

Answer 4

A period of cell growth in preparation for cell division. All cell components excluding chromosomes are duplicated

Question 5

S (synthesis-phase) Cell Cycle (5 hrs)

Answer 5

DNA (chromosome) replication occurs. A second double helix is formed

Question 6

G2 Cell Cycle (3-4 hrs)

Answer 6

Resting phase before cell division. Checks chromosomes for replication error and repairs are made

Question 7

Mitosos (2hrs)

Answer 7

Dividing of cell into identical daughter cells. Daughter cells recieve 1 of each chromosome

Question 8

Cytokenisis

Answer 8

Daughter cells form and split from eachother

Question 9

Mitosis Stages

Answer 9

Prophase, ProMetaphase, Metaphase, Anaphase + Telophase and cytokinesis

Question 10

Prophase Outline

Answer 10

Chromosome containing 2 sister double helixes condenses and becomes visible. Bipolar spindles develop

Question 11

Prometaphase

Answer 11

Nuclear envelope dissolves. Chromosomes migrate to equatorial plate (metaphase plate)

Question 12

Metaphase

Answer 12

Fully condensed chromosomes exist at metaphase plate. Kinetochore microtubule of aster poles are attached to centromeres

Question 13

Anaphase

Answer 13

Centromere splits and chromosome pairs are pulled to opposite sides

Question 14

Telophase

Answer 14

Chromosomes at poles recondense, nuclear membrane reforms and cytoplasm begins to split

Question 15

Cytokenisis Outline

Answer 15

Cytoplasm fully splits into 2 identical daughter cells

Question 16

Centrosome Def.

Answer 16

Form cell poles, microtubule organisation centre. Polar fibres grow out

Question 17

Kinetochore Def.

Answer 17

Protein structure at centromere attaches chromatids to spndle fibres via kinetochore microtubules

Question 18

Centromere Def.

Answer 18

DNA sequence necessary for cell segregation during division. Chromatids without centromeres won’t be separated by spindle fibres pulling them apart (as they couldn’t attach), thus won’t be passed onto daughter cells

Question 19

Meiosis Def.

Answer 19

Produces haploid cells (gametes)

Question 20

How many times does a cell divide by meiosis

Answer 20

2

Question 21

Stages of Meiosis (I and II)

Answer 21

Prophase I, Metaphase I, Anaphase I, Telophase & cytokinesis I. Prophase II, Metaphase II, Anaphase II and Telophase & Cytokinesis II

Question 22

Differences at metaphase mitosis and meiosis

Answer 22

In meiosis parental and maternal homologs associate and stand at metaphase plate in bivalent formation. In mitosis parental and maternal homologs don’t associate and stand signally at metaphase plate

Question 23

Number of rounds of DNA synthesis in both mitosis and meiosis

Answer 23

1

Question 24

Differences in mitosis and meiosis

Answer 24

cell divides once in mitosis and twice in meiosis, parental & maternal homologs associate in meiosis and don’t in mitosis, recombination is abnormal in mitosis but frequent in meiosis, daughter cells differ (haploid) in meoisis and are identical (diploid) in mitosis

Question 25

2 Ways Diversity Is Created in Meiosis

Answer 25

Recombination and Independent Assortment

Question 26

Recombination Def.

Answer 26

Breakage of the DNA duplex in 1 maternal and 1 paternal chromatid + joined at ends. DNA is transferred (none lost or gained)

Question 27

Non-Disjunction

Answer 27

When recombination accidentally happens in mitosis and DNA sequences are lost

Question 28

Independent Assortment Def

Answer 28

Spindle fibres pulls 2 chromatids towards pole. With each chromatid having an equal chance to be pulled a specific pole

Question 29

Chiasmata DEf.

Answer 29

Same function as centromere acts as a crossing over point between homologs. Holds homologs together until Anaphase I. Lach of chiasmata may result in incorrect chromosome number in cells

Question 30

Where in meiosis to oocytes stop before puberty

Answer 30

Prophase 1

Question 32

Name of cell gametes form from in females

Answer 32

Ooginium to
primary oocyte

Question 33

Name of cell gametes form from in males

Answer 33

Spermatotangium and primary spermocyte

Question 34

Polar body function in gamete formation

Answer 34

Get rid of spare set of chromosome

Question 35

Gamete cell in females

Answer 35

Ovum

Question 36

Gamete cell in males

Answer 36

Spermatoza

Question 37

Allele Def.

Answer 37

Copy of a gene. Vary by their DNA base sequence

Question 38

Polymorphism

Answer 38

In populations genes have many alleles

Question 39

GTA and GTB genes

Answer 39

Stimulates glycotransferes which glycosates proteins in proteins and lipids on cell membrane. Forming A and B antigens

Question 40

What would result in heterozygous GTA and GTB

Answer 40

Co. Dominance AB blood type

Question 41

GTA transfers

Answer 41

N-acetylgalactosamine

Question 42

GTB Tranfers

Answer 42

Galactose

Question 43

GTO genes

Answer 43

Doesn’t activate an enzyme

Question 44

Human Inherited Disease

Answer 44

Genetic (DNA) defects. Genotype effects Phenotype

Question 45

Monogenic Defects Def.

Answer 45

Disease carried by dominant/recessive gene. Follows simple Mendelian pattern

Question 46

Polygenic Defects

Answer 46

Several gene interactions cause disease. Non-Mendelian

Question 47

Euchromatic Def.

Answer 47

Mainly C-G pairs + more transcriptionally active

Question 48

Heterochromatin

Answer 48

Mainly A-T pairs and less transcriptionally active