Unit 2 lecture 5 10/3/22

Question 1

The continuity of life is based on the reproduction of cells, or ______

Answer 1

Cell division

Question 2

Cell division is an integral part of the _____, the life of a cell from formation to its own division

Answer 2

Cell cycle

Question 3

DNA is passed from one generation of cells to the next with remarkable ____

Answer 3

fidelity

Question 4

All the DNA in a cell constitutes the cell’s ____

Answer 4

Genome

Question 5

DNA molecules in a cell are packaged into

Answer 5

chromosomes

Question 6

Eukaryotic chromosomes consist of ______a complex of DNA and protein

Answer 6

Chromatin

Question 7

_____(nonreproductive cells) have two sets of chromosomes

Answer 7

Somatic cells

Question 8

______(reproductive cells: sperm and eggs) have one set of chromosomes

Answer 8

Gametes

Question 9

Each duplicated chromosome has two _______joined identical copies of the original chromosome

Answer 9

sister chromatids

Question 10

The ______is where the two chromatids are most closely attached

Answer 10

centromere

Question 11

Eukaryotic cell division consists of three major phases:
1.______
2.______
3.______

Answer 11

1.Interphase: when growth and DNA replication occur
2.Mitosis: the division of the genetic material in the nucleus
3.Cytokinesis: the division of the cytoplasm

Question 12

Gametes are produced by a variation of cell division called ______

Answer 12

meiosis

Question 13

Meiosis yields ______daughter cells that have only one set of chromosomes, half as many as the parent cell

Answer 13

nonidentical

Question 14

Interphase (about 90% of the cell cycle) can be divided into subphases
1.
2.
3.

Answer 14

1.G1 phase (“first gap”)
2.S phase (“synthesis”)
3.G2 phase (“second gap”)

Question 15

During G1 the cell grows in size and synthesis of 1._____ and 2.____necessary for DNA replication occurs

Answer 15

1.mRNA
2.proteins

Question 16

During S phase, ____ replication occurs

Answer 16

DNA

Question 17

_______ is period of rapid growth in final preparation for mitosis and cell division and ends with the onset of prophase in mitosis; not all cells need it

Answer 17

G2 phase

Question 18

Mitosis relates specifically to the division of the _____

Answer 18

nucleus

Question 19

Includes five distinct stages:
1.
2.
3.
4.
5.

Answer 19

1.Prophase
2.Prometaphase
3.Metaphase
4.Anaphase
5.Telophase

Question 20

_____overlaps the latter stages of mitosis

Answer 20

Cytokinesis

Question 21

The ________ is a structure made of microtubules and associated proteins and It controls chromosome movement during mitosis

Answer 21

mitotic spindle

Question 22

The mitotic spindle includes the 1.________the 2._______and the 3._____

Answer 22

1.centrosomes
2.spindle microtubles
3.asters

Question 23

In animal cells, assembly of spindle microtubules begins in the _______the microtubule organizing center

Answer 23

centrosomes

Question 24

The centrosome replicates during _______forming two centrosomes that migrate to opposite ends of the cell during prophase and prometaphase

Answer 24

interphase

Question 25

An _____(radial array of short microtubules) extends from each centrosome

Answer 25

aster

Question 26

During ______, the chromatin condense and become visible, nucleoli disappear, and the mitotic spindle begins to form

Answer 26

Prophase

Question 27

During _____,some spindle microtubules attach to the kinetochores of chromosomes and begin to move the chromosomes

Answer 27

prometaphase

Question 28

Formed in prometaphase, _______are protein complexes that assemble on sections of DNA at centromeres

Answer 28

kinetochores

Question 29

At metaphase the centromeres of all the chromosomes are at the ________ an imaginary structure at the midway point between the spindle’s two poles

Answer 29

metaphase plate

Question 30

In ______sister chromatids separate and move along the kinetochore microtubules toward opposite ends of the cell

Answer 30

anaphase

Question 31

During ______, the nuclear envelopes begin to reform, mitotic spindles begin to dissolve, and cell begins cytokinesis

Answer 31

telophase

Question 32

________is where daughter cells actually split, and begins during anaphase or telophase and the spindle eventually disassembles

Answer 32

Cytokinesis

Question 33

In animal cells, cytokinesis occurs by a process known as cleavage forming a ________ and In plant cells, a cell plate forms during cytokinesis

Answer 33

cleavage furrow

Question 34

Prokaryotes (bacteria and archaea) reproduce by a type of cell division called _______

Answer 34

binary fission

Question 35

The cell cycle is driven by specific _________ present in the cytoplasm

Answer 35

signaling molecules

Question 36

For many cells, the ______ seems to be the most important If a cell receives a go-ahead signal at the G1 checkpoint, it will usually complete the S, G2, and M phases and divide

Answer 36

G1 checkpoint

Question 37

If the cell does not receive the go-ahead signal, it will exit the cycle, switching into a nondividing state called the ______

Answer 37

G0 phase

Question 38

The cell cycle is regulated by a set of regulatory proteins and protein complexes including 1.____and proteins called 2._____

Answer 38

1.kinases
2.cyclins

Question 39

An example of an internal signal occurs at the M phase checkpoint Attachment of all of the kinetochores activates a regulatory complex, which then activates the enzyme _______

Answer 39

separase

Question 40

______ allows sister chromatids to separate, triggering the onset of anaphase

Answer 40

Separase

Question 41

Some external signals are ______ proteins released by certain cells that stimulate other cells to divide

Answer 41

growth factors

Question 42

Another example of external signals is ________ in which crowded cells stop dividing

Answer 42

density-dependent inhibition

Question 43

Most animal cells also exhibit ________ in which they must be attached to a substratum in order to divide

Answer 43

anchorage dependence