CELL CYCLE Flashcards
1
Q
2 types of cell reproduction
A
- Prokaryotes (Binary Fission)
- Eukaryotes (Mitosis and Meiosis)
2
Q
Type of Cell Reproduction which produces an identical cell to the parent cell
A
Binary Fission
3
Q
Cell Reproduction for cell growth and repair; produces cells with different traits
A
Mitosis
4
Q
Cell Reproduction controlling the production of sex cells or gametes
A
Meiosis
5
Q
2 Reasons why cells divide
A
- DNA Overload
- Exchange of Materials
6
Q
Binary Fission process
A
- DNA Replication
- Chromosome Segragation
- Cytokinesis
7
Q
Cell Cycle
A
Interphase (G1-S-G2)
Cell Division/M phase (P-M-A-T)
Cytokinesis
8
Q
longest stage in the cell cycle
A
Interphase
9
Q
Phase that focuses on cell growth and increase in cell’s size
A
G1
10
Q
Phase of DNA and chromosome replication
A
S Phase
11
Q
Preparation for Mitosis; organelles double
A
G2
12
Q
Dividing Stage in cell cycle
A
M phase
13
Q
Control system in cell cycle
A
Checkpoint
14
Q
Where do cells go when they only undergo cell cycle once
A
G0
15
Q
Restriction Point - restriction to enter S phase
A
G1 checkpoint
16
Q
Checks for DNA damage and prevents reduplication of DNA
A
S Checkpoint
17
Q
allows entry to mitosis
A
G2 Checkpoint
18
Q
Checks whether mitosis is complete
A
M Checkpoint
19
Q
3 Responsible in Checkpoints
A
- Cyclins
- Cyclin-dependent kinases
- p53 (tumor suppressors)
20
Q
Responsible for Checkpoints; undergo constant cycle of synthesis and degradation
A
Cyclin
21
Q
Kinases which activate/deactivate another protein through phosphorylating them (G1 and G2 checkpoints)
A
CDK
22
Q
Tumor suppressor genes; guardian of genome(prevents gene mutation); DNA repair; apoptosis; allows cell to continue after repair
A
p53
23
Q
Malfunctions during cell cycle
A
- Cancer
- Genetic Disorder
24
Q
uncontrolled abnormal cell division forms tumors or what cells
A
cancer
25
changes or mutations to DNA within cells causes production of
Cancerous cells
26
Tumors may be ________tumors which are those that stay in their primary location. Or _________tumors which have cells that grow uncontrollably and spread locally and/or to distant sites.
Benign ; Malignant
27
Risk Factors of Cancer
- lifestyle
- family history
- genetic disorder
- certain viruses (cervical/prostate)
- environmental exposure (fertilizers, radiation, carcinogens)
28
3 ways to treat tumors
1. Chemotherapy (Oral/Intravenous)
2. Surgery
3. Radiation Therapy
29
Disorders caused by abnormal cell division and genes; errors during dividing sex cells; exposure to substances that can cause birth defects
Genetic Disorders
30
21st chromosome is 3 instead of 2; a mistake in reproductive cells; trisomy 21
Down Syndrome
31
X chromosome missing in female (45, XO)
Turner Syndrome
32
More X chromosomes in male (47, XXY)
Klinefelter syndrome
33
extra X chromosome in female (47, XXX)
Trisomy X syndrome
34
additional copy of chromosome 13 in some body cells (Trisomy 13)
Patau Syndrome
35
additional copy of chromosome 18; physical manifestations (Trisomy 18)
Edward Syndrome
36
Structural Abnormalities may be
1. Deletion
2. Duplication
3. Translocation
4. Inversion
37
deletion of genetic material (5p minus syndrome)
Cri-du-chat syndrome
38
During interphase, the DNA in the cell is called
chromatin
39
two identical strands of DNA that make up the duplicated chromosome.
sister chromatids
40
The sister chromatids are held together by a structure called the _______
centromere.
41
Before a cell divides, it makes copies of all its _______
organelles.
42
During ________, duplicated DNA condenses into chromosomes.
prophase
43
During ________, the chromosomes line up in the middle of the cell.
metaphase
44
During___________, sister chromatids in each duplicated chromosome separate and
are pulled in opposite directions by the spindle fibers
anaphase
45
During ___________, chromosomes begin to uncoil, and two new identical nuclei form.
G. Dividing the Cell’s Components
telophase
46
In animal cells, a(n) ___________ in the middle of the cells gets deeper until the cell
membrane comes together to divide the cell.
furrow
47
In plant cells, a(n) ___________ grows outward toward a new cell wall until two new
cells form.
cell plate
48
The cell cycle results in two new __________ that are genetically identical to each
other and to the original cell, which no longer exists.
daughter cells
49
Chromosomes come in pairs. Normally, each cell in the human body has __________ pairs of chromosomes
23
50
process of cell division which results in the production of 2 daughter cells from a single parent cell
mitosis
51
mitosis: cell prepares for nuclear division and the package of DNA
Prophase
52
proteins found in centromere
kinetochore
53
Mitosis: cell prepares chromosomes for division; they line up at the center as the spindle fibers attach to their centromeres
metaphase
54
mitosis: chromosomes divide as spindle fibers pull chromosomes apart
anaphase
55
mitosis; cytoplasm divides and DNa spreads out forming 2 nuclei and a cleavage furrow
telophase
56
mitosis produces
2 diploid daughter cells
57
significance o mitosis
- responsible for the development of body organs
- repairs damaged cells
58
division of cells for organs
gastrulation
59
if cells are damaged it would result to
-cancer
-neurodegeneration
60
progressive damage in the nerve cells wherein there is a damage in nerve structure and function
neurodegeneration
61
too much cell death caused by huntingtin interactive protein
huntington's diseases
62
uncontrolled movement
Parkinson's diseases
63
application of mitosis to other disciplines
- agriculture (cloning)
- medicine
- tissue culture
64
the sequence of events by which a cell duplicates its genome, synthesizes the other constituents of the cell and eventually divides into 2 daughter cells
cell cycle
65
T or F: Although cell growth (in terms of cytoplasmic increase) is a continuous process, DNA synthesis occurs only during one specific stage in the cell cycle.
T
66
phase of the cell cycle in which the microtubular apparatus assembles, binds to the chromosomes, and moves the sister chromatids apart.
M phase
67
mitosis
# of divisions =
# of produced cells =
chromosome sets (=n) =
purpose =
- 1 division
- 2 cells
- 1n>1n>;2n>2n
- vegetative growth
68
# of produced cells =
meiosis
chromosome sets (=n) =
purpose =
- 2 divisions
- 4 cells
- 2n>1n
- sexual reproduction; produce sex cells
69
While mitosis was going on, the cytoplasmic organelles, including mitochondria and chloroplasts (if present), were reassorted to areas that will separate and become the daughter cells. The phase of the cell cycle when the cell divides is called __________
cytokinesis
70
marked by the initiation of condensation of chromosomal material. The chromosomal material becomes untangled during the process of chromatin condensation. The centriole, which had undergone duplication during S phase of interphase, now begins to move towards opposite poles of the cell.
prophase
71
- Chromosomal material condenses to form compact Mitotic chromosomes. Chromosomes are seen to be composed of two chromatids attached together at the centromere.
- Initiation of the assembly of mitotic spindle, the microtubules, the proteinaceous components of the cell
Prophase
72
The complete disintegration of the nuclear envelope marks the start of the second phase of mitosis; hence the chromosomes are spread through the cytoplasm of the cell.
metaphase
73
- Spindle fibers attach to kinetochores of chromosomes.
- Chromosomes are moved to spindle equator and get aligned along metaphase plate through spindle fibers to both poles.
Metaphase
74
each chromosome arranged at the metaphase plate is split simultaneously and the two daughter chromatids, now referred to as chromosomes of the future daughter nuclei, begin their migration towards the two opposite poles
anaphase
75
- Centromeres split and chromatids separate.
- Chromatids move to opposite poles.
Anaphase
76
the chromosomes that have reached their respective poles decondense and lose their individuality. The individual chromosomes can no longer be seen, and chromatin material tends to collect in a mass in the two poles.
Telophase
77
- Chromosomes cluster at opposite spindle poles and their identity is lost as discrete elements.
- Nuclear envelope assembles around the chromosome clusters.
- Nucleolus, Golgi complex and ER reform
Telophase
78
- Chromosomes cluster at opposite spindle poles and their identity is lost as discrete elements.
- Nuclear envelope assembles around the chromosome clusters.
- Nucleolus, Golgi complex and ER reform
Telophase
79
process of cell duplication, or reproduction, during which one cell gives rise to two genetically identical daughter cells. The newly formed daughter cells are genetically identical to the parent cell and to each other.
Mitosis
80
Strictly applied, the term ________ is used to describe the duplication and distribution of chromosomes, the structures that carry the genetic information.
mitosis
81
During this process, the cell’s nucleus along with the chromosome is divided to form two new daughter cell nuclei. The daughter nuclei inherit the same number of chromosomes as that of the parent nucleus.
mitosis
82
role of mitosis
- provides new cells for growth and for replacement of worn out cells
83
living processes using mitosis
- development and growth
- cell replacement
- replacement of damaged plant or animal tissue (regeneration)
- asexual reproduction
84
________ helps in the splitting of chromosomes during cell division and generates two new daughter cells. Therefore, the chromosomes form from the parent chromosomes by copying the exact DNA. Therefore, the daughter cells formed as genetically uniform and identical to the parent as well as to each other. Thus,_________ helps in preserving and maintaining the genetic stability of a particular population.
Mitosis
85
allows organisms to reproduce asexually, grow and repair of worn-out or damaged tissues.
mitosis
86
important in sexual reproduction and genetic diversity among sexually reproducing organism
meiosis
87
These two divisions result in four daughter cells (rather than the two daughter cells of mitosis), each with only half as many chromosomes as the parent cell—one set, rather than two. _________reduces the amount of genetic information resulting to its importance in sexual reproduction and genetic diversity among sexually reproducing organism.
Meiosis 1 and 2
- Meiosis
88
Stages of Meiosis
Meiosis 1
- P1
- M1
- A1
- T1
Meiosis 2
- P2
- M2
- A2
- T2
89
Prophase of the first meiotic division is typically longer and more complex when compared to prophase of mitosis. It has been further subdivided into the following five phases based on chromosomal behavior:
1. Leptotene
2. Zygotene
3. Pachytene
4. Diplotene and
5. Diakinesis
90
MEIOSIS: The bivalent chromosomes align on the equatorial plate. The microtubules from the opposite poles of the spindle attach to the pair of homologous.
M1
91
MEIOSIS: The homologous chromo-somes separate, while sister chromatids remain associated at their centromeres.
A1
92
MEIOSIS: The nuclear membrane and nucleolus reappear, cytokinesis follows and this is called as diad of cells. Although in many cases the chromosomes do undergo some dispersion, they do not reach the extremely extended state of the interphase nucleus.
T1
93
MEIOSIS: initiated immediately after cytokinesis, usually before the chromosomes have fully elongated. In contrast to _________ ,___________resembles a normal mitosis.
The nuclear membrane disappears by the end of IT. The chromosomes again become compact.
P2; MEIOSIS 1; MEIOSIS 2
94
MEIOSIS: At this stage the chromosomes align at the equator and the microtubules from opposite poles of the spindle get attached to the kinetochores of sister
M2
95
MEIOSIS: It begins with the simultaneous splitting of the centromere of each chromosome (which was holding the sister chromatids together), allowing them to move toward opposite poles of the cell.
A2
96
Meiosis ends with _________ in which the two groups of chromosomes once again get enclosed by a nuclear envelope; cytokinesis follows resulting in the formation of haploid daughter cells.
Telophase II
97
Importance of Meiosis
- rapid generation of new genetic combinations to sex cells
98
There are three mechanisms that contribute to this genetic variation:
independent assortment,
crossing-over, and
random fertilization.
99
T or F. Humans have 23 pairs of homologous chromosomes. In fact, these 23 chromosomes that you receive from your parents are a matter of chance.
T
100
- The random distribution of homologous chromosomes during meiosis is called ________
independent assortment
101
In __________, maternal and paternal chromosomes lined up at the equator of the cell, but eventually, these are pulled apart randomly at opposite poles in ___________. Each of the 23 pairs segregates or separates independently. Each daughter cell gets one chromosome from each homologous pair.
metaphase I; anaphase I; independent assortment
102
with just four pairs of homologous chromosomes for simplified illustration. With four pairs of homologous chromosomes, you may come up with 24 or 16 possible combinations. Thus, 223 (about eight million) with different gene combinations can be produced from one original cell mechanism alone for humans according to this mechanism
Independent Assortment
103
alignment of chromosomes in the middle of the metaphase plate is random and can result in astounding possibilities in genetic variability because of this mechanism
Independent Assortment
104
This occur during prophase I of meiosis, where chromosomes line up in the process called synapsis, while sections of their DNA are exchanged
CRossing over and Random Fertilization
105
DNA exchange during crossover adds more ______________to the independent assortment of chromosomes that occur later in meiosis.
recombination probabilities
106
because the zygote that forms a new individual is created by the random fusion of two gametes, _________ squares the number of possible outcomes (223 x 223 = 64 trillion).
fertilization
107
T or F. Crossing-over between homologous chromosomes doesn't add to genetic variability compared to independent assortment
F; adds to genetic variability
