Cell Divison (Exam #3)

Front 1

how are all cells reproduced?

Back 1

cell division

Front 2

why do cells divide?

Back 2

-organismal reproduction
-growth
-repair

Front 3

what are two forms of cell division?

Back 3

-asexual
-sexual

Front 4

what is asexual cell division(mitosis)?

Back 4

-daughter cells are identical copies of mother cells (clones)
-occurs in all organisms

Front 5

what is sexual cell division?

Back 5

daughter cells are not identical copies to the mother cell

Front 6

how do prokaryotes divide?

Back 6

binary fission

Front 7

how does binary fission occur?

Back 7

-DNA is duplicated
-one chromosome moved to each side of the cell
-cell is split into two
-takes 20 minutes

Front 8

what process
-grows and duplicates organelles
-duplicates DNA
-divides and seperates DNA to opposite sides of the cell
-and splits the cell into 2 seperate cells

Back 8

eukaryote division

Front 9

what term best describes all the DNA in a cell?

Back 9

genome

Front 10

how is the human genome (DNA) organized?

Back 10

by 46 chromosomes

Front 11

one linear DNA molecule wound around proteins is equal to what?

Back 11

one chromatid (eukaryotic chromosome)

Front 12

Eukaryotic DNA can be coiled into what extents?

Back 12

-unwound
-condensation

Front 13

what can be duplicated and condensed?

Back 13

DNA

Front 14

what is a centromer?

Back 14

connection between 2 chromatids in one chromosome

Front 15

one chromosome is equal to 2 ... ?

Back 15

chromatids

Front 16

what are the three stages of the eukaryotic cell division?

Back 16

-cell growth and DNA replication
-mitosis (division of the nucleus
-cytokinesis (division of the cell)

Front 17

the time between two divisions is one ...?

Back 17

cell cycle

Front 18

the cell growth and DNA replication occur in what phase?

Back 18

the interphase

Front 19

How are the events of a cell regulated?

Back 19

by interal and external controls

Front 20

what checkpoint of the cell cycle is the most important?

Back 20

completes the S, G2, M phases and divide all during the first checkpoint phase of G1

Front 21

During what phase does
-most cells in any organism occur in this stage
-the DNA is loose chromatin and the nucleus is present

Back 21

interphase

Front 22

What 5 stages occur under mitosis (m-phase)?

Back 22

-prophase
-prometaphase
-metaphase
-anaphase
-telophase

Front 23

what is prophase? (3)

Back 23

-DNA is beginning to condense
-nuclear membrane begins to break down
-spindle begins to form

Front 24

what is the process of prometaphase?

Back 24

-the chromosomes are connected to the spindle microtubles at thier centromere
-the nuclear membrane, ER and golgi finish breaking down

Front 25

what is the metaphase?

Back 25

the chromosomes line up in the center of the cell
(because of "tug-a-war" by the microtubules)

Front 26

what is anaphase?

Back 26

the centomeres seperate and the sister chromatids (each still considered as a chromosome) move toward the opposite poles

Front 27

what is a telophase?

Back 27

-the chromosomes begin to unravel
-the nuclear envelope begins to re-form

Front 28

what occurs in the cytokinesis phase?

Back 28

the cytoplasm seperates

Front 29

what is involved in the interphase? (5 things)

Back 29

-centrosomes (with centriole pairs)
-chromatin (duplicated)
-nucleolus
-nuclear envelope
-plasma membrane

Front 30

what is involved in the prophase? (3)

Back 30

-early mitotic spindle
-centromere
-chromosome(consisting of 2 sister chromatids)

Front 31

what is involved in the prometaphase? (2)

Back 31

-fragments of nuclear envelope
-microtubules

Front 32

what is involved in the metaphase? (3)

Back 32

-metaphase plate
-spindle
-1 centrosome at one spindle pole

Front 33

what is in the anaphase? (1)

Back 33

daughter chromosomes

Front 34

what is involved in the telophase and cytokinesis?

Back 34

-cleavage furrow
-nucleolus forming
-neclear envelope forming

Front 35

what type of cell does this cytokinesis exsist in...
a ring of microfilaments contract until the cell is pinched into two (called the cleavage furrow)?

Back 35

animal cells

Front 36

what type of cell does this cytokinesis exsist in...
cell plate forms between the two cells (eventually forms a cell wall)?

Back 36

in plant cells

Front 37

what is a form of cell division that leads to the production of gametes?

Back 37

meiosis

Front 38

what are gametes?

Back 38

-egg and sperm cells
-contain half the number of chromosomes of an adult body cell

Front 39

what does haploid cells mean?

Back 39

-one set of chromosomes
-from meiosis
-cell= (n)

Front 40

what are somatic cells?

Back 40

-two sets of chromosomes
-from mitosis
-the cells are diploid (2n)

Front 41

what are two forms of cell division?

Back 41

asexual (mitosis)
sexual (fertilization after meiosis)

Front 42

what is asexual cell division?

Back 42

-daughter cells are identical copies of the mother cell (clones)
-occurs in all organisms

Front 43

what is sexual cell division?

Back 43

-daughter cells are not identical copies of the mothers cells
-only occurs in eukaryotes

Front 44

what cell division occurs in only eukaryotes?

Back 44

sexual

Front 45

what type of cell division forms haploid gametes from diploid body cells?

Back 45

meiosis

Front 46

what word is greek meaning "to make small"?

Back 46

meiosis

Front 47

how is sexual reproduction completed?

Back 47

the fusion of gametes (fertilization) to produce a diploid zygote

Front 48

life cycles of sexually reproducing organisms involve what? (2)

Back 48

-the alternation of haploid and
-diploid stages

Front 49

to go from diploid to haploid stages what must a cell go through?

Back 49

meiosis

Front 50

what is the difference between mitosis and meiosis?

Back 50

-(photophase 1)- homologous chromosomes line up (and genetic information is exchanged)
-(After) cytokinesis I, the resulting cells are now haploid but have doubled chromosomes

Front 51

what is the first stage of meiosis prophase I?

Back 51

chromosomes coil and nuclear envelope dissolves

Front 52

what is the second stage of meiosis prophase I?

Back 52

homologues become closey associated in synapsis

Front 53

what happens in the third stage of meiosis prophase I?

Back 53

crossing over occurs between non-sister chromatids

Front 54

what happens in 1st stage of the meiosis metaphase I?

Back 54

terminal chiasmata hold homologues together following cross over

Front 55

what happens in 2nd stage of the meiosis metaphase I?

Back 55

microtubules from opposite poles attach to each homologue (not the sister chromatid)

Front 56

what happens in 3rd stage of the meiosis metaphase I?

Back 56

homologues are aligned at the metaphase plate side-by-side

Front 57

mitosis is after meiosis 1- true or false?

Back 57

true

Front 58

what stage is this...
chiasmata hold homologues together. the kinetochores of sister chromatids fuse and function as one. microtublues can attach to only one side of each centromere... ?

Back 58

-(meiosis I)
-metaphase I

Front 59

what stage is this... microtubules pull the homologous chromosomes apart but sister chromatids are held together...?

Back 59

-(meiosis I)
-anaphase I

Front 60

what stage is this?
homologoues do not pair; kinetochores of sister chromatids remain seperate; microtubules attach to both kineochores on opposite sides of the centromere?

Back 60

mitosis
metaphase

Front 61

what stage is this..
microtubules pull sister chromatids apart?

Back 61

mitosis
anaphase

Front 62

what is the first step of the anaphase I?

Back 62

microtubules of the spindle shorten

Front 63

what is the second step of the anaphase I?

Back 63

homologues are seperated from each other

Front 64

what is the third step of the anaphase I?

Back 64

sister chromatids remain attached to each other at their centromeres

Front 65

what is the first step of the telophase I?

Back 65

nuclear envelopes form around each set of chromosomes

Front 66

what is the second step of the telophase I?

Back 66

each new nucleus is now haploid

Front 67

what is the third step of the telophase I?

Back 67

sister chromatids are no longer identical because of crossing over

Front 68

what are the steps to Meiosis II?

Back 68

prophase II
metaphase II
anaphase II
telophase II

Front 69

what happens in prophase II?

Back 69

nuclear envelopes dissolve and spindle appartus forms

Front 70

what happens in the metaphase II?

Back 70

chromosomes align on metaphase plate

Front 71

what happens in the anaphase II?

Back 71

sister chromatids are seperated from each other

Front 72

what happens in the telephase II?

Back 72

nuclear envelope re-forms; cytokinesis follows

Front 73

plants, fungi, and bacteria have a certain capacity to divde true or false?

Back 73

false they have an unlimited capacity to divide

Front 74

how many times can a animal divide?

Back 74

20-50 divisions

Front 75

what factors influence animal cell division?

Back 75

nutrient availibility
growth factors
cell density
cell size
cancer cells- do not have density dependent inhibition

Front 76

proteins that influence the cell cycle are called what?

Back 76

growth factors

Front 77

what do the proteins do in a growth factor?

Back 77

trigger intracellular signaling systems
-can override cellular controls that otherwise inhibit cell division

Front 78

what is the failure of the cell cycle control?

Back 78

cancer because serveral kinds of genes can disturb the cell cycle when they are mutated

Front 79

what is ...
-common cell replication for growth and repair
-one cell division
-makes 2 cells from 1
-the number of chromosomes stay the same
-daughter cells are genetically identical

Back 79

mitosis

Front 80

what is...
-specific for production of gametes for reproduction
-two cell divisions
-1 cell= 4 cells made
-number of chromosomes is reduced from diploid to haploid
-daughter cells are not genetically identical

Back 80

meiosis