Midterm 2 Flashcards
(183 cards)
1
Q
What are the 3 classes of cells in cell division?
A
Mitotic cells, post-mitotic/differentiate cells, and stem cells
2
Q
Mitotic cells
A
cells that divide all the time in your body
3
Q
What are the 2 theories?
A
1) Programmed longevity of cells and 2) Accumulation of damaged biomolecules
4
Q
Accumulation of damaged biomolecules
A
the idea that as cells divide there are random events that cause damage to biomolecules inside the cell
5
Q
What is a problem with this theory?
A
senescence is a predetermined and precise number
6
Q
Programmed longevity of cells
A
the idea that senescence is programmed inside and hardwired inside the genes of the cells
7
Q
What’s at the end of the chromosomes?
A
telomeres
8
Q
Telomeres
A
a repeat DNA sequence at the end of the chromosomes
9
Q
What is the function of telomeres?
A
stabilizes the chromosomes and prevents the chromosomes from randomly fusing with one another
10
Q
What happens after each successive cell division?
A
telomeres shorten
11
Q
What happens when the telomeres are too short?
A
- telomeres are no longer able to stabilize the chromosomes because they are short
- chromosomes start to break off and fuse together causing the number of chromosomes to change and have a different chromosomal appearance
12
Q
Molecular fidelity
A
the system that is restoring damage
13
Q
What happens when over time cell damage accumulates?
A
cell can no longer divide, the cell cycle arrests, and undergoes senescence
14
Q
What is the most common damage to biomolecules?
A
free radicals
15
Q
Free radicals
A
chemical species that have an unpaired number of electrons
16
Q
How do free radicals cause damage?
A
reacts with other molecules by either removing or adding electrons to it, creating more free radicals
17
Q
What is one common free radical in a biological system?
A
superoxide radical (O2-)
18
Q
What is the most common type of free radicals in a biological system?
A
ROS (reactive oxygen species)
19
Q
ROS
A
oxygen-centered free radicals
20
Q
Examples of ROS
A
superoxide radical (O2-), hydrogen peroxide (H2O2), hydroxyl radical (OH-), NO (nitric oxide)
21
Q
What’s the common cause of free radicals?
A
redox reactions
22
Q
Oxidation-reduction reaction
A
electrons are shuffled between chemical species
23
Q
What are the safeguard (or protective) mechanisms to prevent these free radicals?
A
enzymes and scavengers
24
Q
How do enzymes prevent free radicals?
A
neutralizes free radicals
25
How do scavengers prevent free radicals?
scavengers quench, sequester and prevent radicals from reacting with other things; scavengers DO NOT neutralize free radicals but isolate them
26
Examples of scavengers
vitamin E + vitamin C
27
Where are redox reactions commonly seen in?
ETC or cellular respiration pathway
28
Post-mitotic cells
cells that do not divide in the lifetime of the organism
29
Stem cells
Slow division and can differentiate into other cell types (not identical --> one stem cell + one differentiated cell)
30
These 3 cell types are what?
somatic cells
30
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
31
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
32
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
32
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
32
What are the phases of cell division?
G1, S, G2, and M phase
32
Post-mitotic cells
cells that do not divide in the lifetime of the organism
32
Stem cells
Slow division and can differentiate into other cell types (not identical --> one stem cell + one differentiated cell)
32
These 3 cell types are what?
somatic cells
32
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
32
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
33
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
33
What are the phases of cell division?
G1, S, G2, and M phase
34
G1 phase
35
G2 phase
36
Post-mitotic cells
cells that do not divide in the lifetime of the organism
36
These 3 cell types are what?
somatic cells
36
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
36
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
36
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
37
What are the phases of cell division?
G1, S, G2, and M phase
37
G1 phase
this is where cells grow in size and get bigger
37
G2 phase
prepares itself for M phase
38
M phase
mitosis + cytokinesis
39
Mitosis
Sister chromatids (generated from S phase) line up in the center of the cell and get pulled apart to opposite poles of the cells, ready to be partitioned between two daughter cells to be shared
40
Cytokinesis
the two cells physically seperate and you end up with 2 identical cells at the end (original cell + newly made cell); this is the last step of the M phase
41
Where do cells reside when not dividing
G0 phase
42
G0 phase
dormant phase where the cells are not dividing
43
What is needed for cell division to be promoted?
mitogenic factors
44
What if there are no mitogenic factors?
the cell will remain “quiescence” in the G0 phase
45
Mitogenic factors
factors that induce cell cycle and cell proliferation
46
Examples of mitogenic factors
proteins, hormones, growth hormones, or substances that promote cell division
47
Each phase of the cell cycle has what?
cell cycle checkpoints
48
Cell cycle check points
set of molecular machinery; quality control system to ensure that cell division is happening flawlessly
49
What triggers the cell cycle checkpoints?
mutations, excess mitogenic factors, UV rays, toxins, or anything that stress the cell
50
Post-mitotic cells
cells that do not divide in the lifetime of the organism
50
Stem cells
Slow division and can differentiate into other cell types (not identical --> one stem cell + one differentiated cell)
51
These 3 cell types are what?
somatic cells
52
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
52
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
52
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
52
What are the phases of cell division?
G1, S, G2, and M phase
53
S phase
this is where chromosomes duplicate and replicate
53
G1 phase
this is where cells grow in size and get bigger
53
G2 phase
prepares itself for M phase
53
M phase
mitosis + cytokinesis
54
Mitosis
Sister chromatids (generated from S phase) line up in the center of the cell and get pulled apart to opposite poles of the cells, ready to be partitioned between two daughter cells to be shared
54
Where do cells reside when not dividing
G0 phase
54
Cytokinesis
the two cells physically seperate and you end up with 2 identical cells at the end (original cell + newly made cell); this is the last step of the M phase
54
G0 phase
dormant phase where the cells are not dividing
55
What is needed for cell division to be promoted?
mitogenic factors
55
What of there are no mitogenic factors?
the cell will remain “quiescence” in the G0 phase
56
Mitogenic factors
factors that induce cell cycle and cell proliferation
56
Examples of mitogenic factors
proteins, hormones, growth hormones, or substances that promote cell division
56
Each phase of the cell cycle has what?
cell cycle checkpoints
57
Cell cycle check points
set of molecular machinery; quality control system to ensure that cell division is happening flawlessly
58
What protein is involved in the cell cycle checkpoints?
p53
59
What triggers the cell cycle checkpoints?
mutations, excess mitogenic factors, UV rays, toxins, or anything that stress the cell
60
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
60
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
60
Where do cells reside when not dividing
G0 phase
60
S phase
this is where chromosomes duplicate and replicate
60
Mitogenic factors
factors that induce cell cycle and cell proliferation
60
Post-mitotic cells
cells that do not divide in the lifetime of the organism
60
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
60
What are the phases of cell division?
G1, S, G2, and M phase
60
Cytokinesis
the two cells physically seperate and you end up with 2 identical cells at the end (original cell + newly made cell); this is the last step of the M phase
60
60
Mitosis
Sister chromatids (generated from S phase) line up in the center of the cell and get pulled apart to opposite poles of the cells, ready to be partitioned between two daughter cells to be shared
60
G1 phase
this is where cells grow in size and get bigger
60
What of there are no mitogenic factors?
the cell will remain “quiescence” in the G0 phase
60
What triggers the cell cycle checkpoints?
mutations, excess mitogenic factors, UV rays, toxins, or anything that stress the cell
60
These 3 cell types are what?
somatic cells
60
G0 phase
dormant phase where the cells are not dividing
60
G2 phase
prepares itself for M phase
60
M phase
mitosis + cytokinesis
61
What is needed for cell division to be promoted?
mitogenic factors
61
61
Stem cells
Slow division and can differentiate into other cell types (not identical --> one stem cell + one differentiated cell)
61
Cell cycle check points
set of molecular machinery; quality control system to ensure that cell division is happening flawlessly
61
Each phase of the cell cycle has what?
cell cycle checkpoints
61
Examples of mitogenic factors
proteins, hormones, growth hormones, or substances that promote cell division
61
What protein is involved in the cell cycle checkpoints?
p53
62
Stem cells
Slow division and can differentiate into other cell types (not identical --> one stem cell + one differentiated cell)
62
Post-mitotic cells
cells that do not divide in the lifetime of the organism
63
63
Cell cycle check points
set of molecular machinery; quality control system to ensure that cell division is happening flawlessly
63
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
63
G0 phase
dormant phase where the cells are not dividing
63
Examples of mitogenic factors
proteins, hormones, growth hormones, or substances that promote cell division
63
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
63
S phase
this is where chromosomes duplicate and replicate
63
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
63
Cytokinesis
the two cells physically seperate and you end up with 2 identical cells at the end (original cell + newly made cell); this is the last step of the M phase
63
What of there are no mitogenic factors?
the cell will remain “quiescence” in the G0 phase
63
These 3 cell types are what?
somatic cells
63
What are the phases of cell division?
G1, S, G2, and M phase
63
M phase
mitosis + cytokinesis
63
Each phase of the cell cycle has what?
cell cycle checkpoints
63
What triggers the cell cycle checkpoints?
mutations, excess mitogenic factors, UV rays, toxins, or anything that stress the cell
63
What is needed for cell division to be promoted?
mitogenic factors
63
G2 phase
prepares itself for M phase
63
Mitosis
Sister chromatids (generated from S phase) line up in the center of the cell and get pulled apart to opposite poles of the cells, ready to be partitioned between two daughter cells to be shared
64
Where do cells reside when not dividing
G0 phase
64
G1 phase
this is where cells grow in size and get bigger
64
What protein is involved in the cell cycle checkpoints?
p53
64
Mitogenic factors
factors that induce cell cycle and cell proliferation
65
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
65
Post-mitotic cells
cells that do not divide in the lifetime of the organism
65
These 3 cell types are what?
somatic cells
66
Stem cells
Slow division and can differentiate into other cell types (not identical --> one stem cell + one differentiated cell)
66
Mitosis
Sister chromatids (generated from S phase) line up in the center of the cell and get pulled apart to opposite poles of the cells, ready to be partitioned between two daughter cells to be shared
66
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
66
Cytokinesis
the two cells physically seperate and you end up with 2 identical cells at the end (original cell + newly made cell); this is the last step of the M phase
66
G1 phase
this is where cells grow in size and get bigger
66
S phase
this is where chromosomes duplicate and replicate
66
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
66
M phase
mitosis + cytokinesis
66
G2 phase
prepares itself for M phase
66
What are the phases of cell division?
G1, S, G2, and M phase
66
Where do cells reside when not dividing
G0 phase
67
G0 phase
dormant phase where the cells are not dividing
67
Each phase of the cell cycle has what?
cell cycle checkpoints
67
Mitogenic factors
factors that induce cell cycle and cell proliferation
67
What of there are no mitogenic factors?
the cell will remain “quiescence” in the G0 phase
67
Examples of mitogenic factors
proteins, hormones, growth hormones, or substances that promote cell division
67
Cell cycle check points
set of molecular machinery; quality control system to ensure that cell division is happening flawlessly
67
What protein is involved in the cell cycle checkpoints?
p53
67
What triggers the cell cycle checkpoints?
mutations, excess mitogenic factors, UV rays, toxins, or anything that stress the cell
67
What is needed for cell division to be promoted?
mitogenic factors
68
69
Post-mitotic cells
cells that do not divide in the lifetime of the organism
69
Stem cells
Slow division and can differentiate into other cell types (not identical --> one stem cell + one differentiated cell)
70
What is the issue with somatic cells?
cannot pass on their genetic information or traits to their offspring
70
These 3 cell types are what?
somatic cells
70
Examples of post-mitotic cells
heart cells, skeletal muscle cells, and brain cells
70
Examples of semi-miotic cells
liver cells, visual cells, and hair follicles
71
S phase
this is where chromosomes duplicate and replicate
71
What are the phases of cell division?
G1, S, G2, and M phase
71
G2 phase
prepares itself for M phase
72
G1 phase
this is where cells grow in size and get bigger
72
M phase
mitosis + cytokinesis
72
Mitosis
Sister chromatids (generated from S phase) line up in the center of the cell and get pulled apart to opposite poles of the cells, ready to be partitioned between two daughter cells to be shared
72
Cytokinesis
the two cells physically seperate and you end up with 2 identical cells at the end (original cell + newly made cell); this is the last step of the M phase
73
Where do cells reside when not dividing
G0 phase
73
G0 phase
dormant phase where the cells are not dividing
74
What is needed for cell division to be promoted?
mitogenic factors
74
What of there are no mitogenic factors?
the cell will remain “quiescence” in the G0 phase
75
Mitogenic factors
factors that induce cell cycle and cell proliferation
75
Examples of mitogenic factors
proteins, hormones, growth hormones, or substances that promote cell division
76
Each phase of the cell cycle has what?
cell cycle checkpoints
76
Cell cycle check points
set of molecular machinery; quality control system to ensure that cell division is happening flawlessly
77
What triggers the cell cycle checkpoints?
mutations, excess mitogenic factors, UV rays, toxins, or anything that stress the cell
77
What protein is involved in the cell cycle checkpoints?
p53
