Chapter 12

Question 1

The life of a cell from the time it is first formed from a dividing parent cell until its own division into two cells is called the

Answer 1

Cell Cycle

Question 2

All of a cells genetic information in DNA is called

Answer 2

Genome

Question 3

DNA molecules are packaged into

Answer 3

Chromosomes

Question 4

Eurkaryotic chromosomes that are a complex of DNA and the associated protien molecules are called

Answer 4

Chromatid

Question 5

Are units that specify an organism’s inherited traits. Each single chromosome contains one very long, linear DNA molecule that carries several hundred to a few thousand

Answer 5

Genes

Question 6

Each duplicated chromosome has two

Answer 6

Sister Chromatids

Question 7

Sister Chromatids are initially attached all along their lenghts by adhesive protein complexes known as

Answer 7

Cohesions

Question 8

Specialized region where the two sister chromatids are most closely attached “waist”

Answer 8

Centromere

Question 9

Division of the nucleus

Answer 9

Mitosis

Question 10

Division of the cytoplasm

Answer 10

Cytokinesis

Question 11

What are the 2 phases of the cell cycle

Answer 11

Mitotioc and interphase

Question 12

Mitotic phase includes what

Answer 12

Mitosis and cytokinesis-shortest part of the cell cycle

Question 13

What is interphase

Answer 13

when cell growth occcurs and chromosomes are copied-90% of cell cycle is in this phase

Question 14

Stages of interphase

Answer 14

G1-First gap
S-DNA synthesis
G2-Second gap

Question 15

Subcellular region containing materials that function throughout the cell cycle to organize the cell’s microtubules

Answer 15

Centrosome

Question 16

A radial array of short microtubules that extends from each centromere

Answer 16

Aster

Question 17

Structure of proteins associated with specific sections of chromosomal DNA at the centromere where the spindle microtubules attach are called

Answer 17

Kinetochores

Question 18

The imaginary plane midway between the spindles of the 2 poles where the centromeres of all duplicate chromosomes line up is called

Answer 18

Metaphase plate

Question 19

What is cytokinesis in an animcal cell

Answer 19

Cleavage furrow-a shallow groove in the cell surface neat the metaphase plate

Question 20

What is cytokinesis in a plant cell

Answer 20

No cleavage furrow-a cell plate forms which enlarges to form a cell wall between 2 daughter cells

Question 21

How do prokaryotes reproduce?

Answer 21

Binary Fission “Origin of replication”

Question 22

Binary Fission consists of

Answer 22

Single Bacterial chromosome consists of a circular DNA molecule and associated protein

Question 23

Frequency of cell division varies with

Answer 23

Type of cell

Question 24

What is G0 phase?

Answer 24

Non dividing state–i.e. nerve cells

Question 25

What controls the cell cycle?

Answer 25

Driven by specific signaling molecules present in the cytoplasm

Question 26

Cyclic operating set of molecules in the cell that both triggers and coordinates key events in the cell cycle is called

Answer 26

Cell cylce control system

Question 27

There is a lot of cell cycle controls in cancer cells

Answer 27

- Cancer cells do not heed to normal signals that regulate the cell cycle - Divide excessively and invade other tissues - Do not stop dividing when growth factors are depleated - Transformation converts a normal cell into a cancer cell - May proliferate and form a tumor, a mass of abnormal cells

Question 28

Benign tumor

Answer 28

If abnormal cells in lump remain at original site

Question 29

What is a malignant tumor

Answer 29

abnormal cells becomes invasive enough to impair the functions of one or more organs

Question 30

Details of maligant tumor

Answer 30

- Excessive proliferation - May have unusual number of chromosomes - Metabolism may be disabled - May cease to function in any constructive pathway - Changes on cell surface can cause cancer cells to lose attachements to neighboring cells and this all them to spead into nearby tissues-Metastasis - May secrete signal molecules that cause blood vessels to grow toward tumor

Question 31

Most cells are in nondividing phase G0 except cancer cells because

Answer 31

Cancer cells are actively dividing and often skip G0

Question 32

Drugs that are toxic to actively dividing cells are admistered through circulatory system. These drugs interfere with specific steps in the cell cycle

Answer 32

Chemotherapudic

Question 33

Drug taxol

Answer 33

freezes mitotoc spendle-stops actively dividing cells from proceeding past metaphase

Question 34

Side effects to chemotherapy

Answer 34

Often due to drug's effects on normal cells that divide often 1. Nausea-effects on intestinal cells 2. Loosing hair-effects on hait follicle cells 3. Susceptible to infecction-effects on immune system cells

Question 35

Cellular transformation always involves...

Answer 35

The alteration of genes that somehow influence the cell cycle control system

Question 36

Most of the cell cycle is spent in?

Answer 36

Interphase

Question 37

When a cell is not dividing, it is in what phase?

Answer 37

G0

Question 38

When DNA replication occurs what stage of cell cycle is that?

Answer 38

S

Question 39

A chromosome that has not replicated has how many chromatids?

Answer 39

Zero

Question 40

A replicated chromosome has how many chromatids?

Answer 40

2

Question 41

Division of the nucleus, producing 2 identical daughter cells is called?

Answer 41

Mitosis

Question 42

How does reproduction of prokaryotes occur?

Answer 42

Binary Fission

Question 43

Most body cells are in what phase?

Answer 43

G0

Question 44

Correct order of mitosis

Answer 44

Prophase Metaphase Anaphase Telophase

Question 45

Which phase do the chromosomes meet at the middle of the nucleus?

Answer 45

Metaphase

Question 46

Which phase do the chromatids seperate and become chromosomes?

Answer 46

Anaphase

Question 47

During G1 how many chromatids per chromosome

Answer 47

Zero

Question 48

During G2 how many chromatids per chromosome

Answer 48

2

Question 49

How many chromatids per chromosome in the beginning of mitosis

Answer 49

2

Question 50

Chromosomes condense and becomes visible in this phase

Answer 50

Prophase

Question 51

Chromosomes line up in the middle of cell in this phase

Answer 51

Metaphase

Question 52

Includes genes that determine an indiviuals sex

Answer 52

X and Y chromosomes

Question 53

Gamtes have how many chromosomes in karotype

Answer 53

23

Question 54

Ordering of human chromosomes images displaying each chromosomes of a single cell

Answer 54

Karotype

Question 55

In a cell that has completed meiosis one has

Answer 55

half the amount of DNA of the cell that began

Question 56

Common characteristics of a karotype

Answer 56

Lenght, Chromsomes position, staining pattern, amd traits coded for

Question 57

Conclusion of Meiosis 1

Answer 57

Homologous pair seperate

Question 58

Product is 2 genetically different daughter cells

Answer 58

Meiosis 1

Question 59

Independent assortment of chromosomes occur

Answer 59

Meiosis 1

Question 60

Occurs in meiosis but not in mitosis

Answer 60

Synapsis of chrosomsomes

Question 61

What is a tetrad

Answer 61

2 sets of sister chromosomes that have synpased

Question 62

What phase is when tetrads allign at equator

Answer 62

Metaphase 1

Question 63

Sister chromatids disjoin and seperate

Answer 63

Anaphase 2

Question 64

23 chromosomes in gamets can produce how many possibilites

Answer 64

8 million

Question 65

How often does crossing over occur

Answer 65

1-2 per chromosome

Question 66

When homologous pairs cross over

Answer 66

Specific protein break and re-join

Question 67

Replicated chromosome

Answer 67

Chromatid

Question 68

Crossing over occurs in

Answer 68

Prophase