(L4) Cellular Reproduction Flashcards
(92 cards)
1
Q
where the proteins are made; the only organelles in prokaryotic cells
A
Ribosomes
2
Q
Don’t have define organelles aside from the ribosome
A
EUKARYOTIC CELLS
3
Q
– is a structure within the cytoplasm that
performs a specific job in the cell
A
Organelle
4
Q
allow eukaryotic cells to carry out more functions
compared to prokaryotic cells. This allows eukaryotic
cells to have greater cell specificity.
A
Organelle
5
Q
provide energy to the cell
A
Mitochondria
6
Q
store substances in the cells
A
Vacuoles
7
Q
Prokaryotic cells reproduce by a process that is called
A
binary fission
8
Q
during _______, the single-celled DNA molecule replicates and the original cell is divided into 2 identical daughter cells
A
binary fission
9
Q
The DNA in such cells is contained in a single circular
chromosome called _______ within the cytoplasm
A
plasmids
10
Q
The reproductive process starts with the ___________
A
replication of the chromosome
11
Q
EXPLAIN BINARY FISSION
A
- 2 chromosomes/plasmids goes to opposite poles
- middle plasma membrane meet at the center
- middle plasma membrane connects and fissions to form 2 daughter cells
12
Q
Eukaryotes grow and reproduce through a process called
A
mitosis
13
Q
The life of eukaryotic cells is characterized by a cell cycle
with 2 major phases:
A
Interphase and Cell Division
14
Q
The cell takes in nutrients, grows, and duplicates its
chromosomes
A
Interphase
15
Q
CELL DIVISION:
The nucleus divides in a process called mitosis and then
the divided nuclei are established in separate cells in a
process called ________
A
cytokinesis
16
Q
There are 2 different types of cellular reproduction. These
processes are responsible for creating different types of cells.
A
- Mitosis
2. Meiosis
17
Q
A process that creates a nearly exact copy of the original
cell
A
MITOSIS
18
Q
Somatic cells, which include nearly all human cells,
are created by this process
A
MITOSIS
19
Q
different form of reproduction that leads to the production of germ cells, or sex cells
A
MEIOSIS
20
Q
Special type of division that occur only in gametic cells
A
MEIOSIS
21
Q
refers to the threadlike appearance of chromosomes as the cell prepares to divide
A
“Mitosis” = “Thread”
22
Q
Process in which a eukaryotic cell nucleus splits in 2,
followed by division of the parent cell into 2 daughter cells
A
Mitosis
23
Q
5 PHASES OF MITOSIS
A
IPMAT
- Interphase
- Prophase
- Metaphase
- Anaphase
- Telophase
24
Q
the cell grows and makes a copy of its DNA
A
Interphase
25
the DNA is condensed down into chromosomes
Prophase
26
the chromosomes align in the middle
Metaphase
27
chromosomes are pulled apart
Anaphase
28
the nuclear membrane starts to reform. Around the 2 nuclei, appearance of the cleavage furrow is seen. Cytokinesis then follows. So, the furrow pinched together then the 2 new cells are formed
Telophase
29
BRIEFLY EXPLAIN IPMAT PHASES:
1. Interphase: DNA replication
2. Prophase: condense DNA to chromosome
3. Metaphase: chromosome at the middle
4. Anaphase: chromosome pulled apart
5. Telophase: cleavage furrow then Cytokinesis
30
Differences between Binary Fission & Mitosis:
BF: Uncondensed and Moves to poles
MTS: Condensed and Spindles
31
generated by centrioles to pull apart the chromosomes
spindles
32
Common about Binary Fission and Mitosis:
DNA copied and Cell Divides
33
INTERPHASE:
Outside of the nucleus are __________, these
structures are critical for the process of cell division
2 centrosomes
34
During interphase, ______ extend from these
| centrosomes
microtubules
35
3 STEPS OF PREPARATION FOR DIVISION IN MITOSIS:
| 3 PROCESSES IN INTERPHASE
1. G1 PHASE
2. S PHASE
3. G2 PHASE
36
Also called the first gap phase, the cell grows physically
larger, copies or organelles, and makes the molecular
building blocks it will need in later steps.
G1 PHASE
37
the cell synthesizes a complete copy of the
| DNA in its nucleus.
S PHASE
38
- a microtubule organizing structure is called the
- helps separate DNA during M (mitosis)
phase
centrosome
39
During this phase the cell grows more, makes proteins
and organelles, and begins to reorganize its contents in
preparation for mitosis.
G2 PHASE
40
EXPLAIN BRIEFLY THE 3 STEPS OF PREPARATION OF DIVISION:
1. G1 PHASE: absorption of nutrients necessary for the later steps
2. S PHASE: synthesis of DNA and centrosomes
3. G2 PHASE: making of proteins and organelles
41
The G1, S, and G2 phases together are known as
Interphase
42
It is said that the average mammalian cell cycle last about
_______ and its transition of the cell from one
interphase through cell division and back to interphase.
17-18 hours
43
longest; lasts about 9 hrs. cells are metabolically active during this phase, and this is when protein synthesis takes place. A cell might be permanently arrested at this phase if it does not undergo further division.
G1 PHASE
44
arrested phase is referred to as
Gap 0 (G0) phase
45
– lasts about 5 hrs. in mammalian cells. This is when DNA synthesis occurs. DNA replicates itself and the chromosomes then consist of 2 identicalsister chromatids. Some DNA replicate early in the this phase and some replicate later.
S PHASE
46
– lasts about 3 hrs. during this phase, the cell
prepares to undergo cell division. Then the completion of
this phase represents the end of the interphase.
G2 Phase
47
Final stage of the cell cycle; very important. Lasts about
1-2 hours in most mammalian cells. It is the process by
which cells reproduce themselves creating 2 daughter
cells that are genetically identical to one another and to
the original parent cell.
MITOSIS
48
```
Answer with the corresponding hours of the phases:
G1:
S:
G2:
Mitotic Phase:
```
G1: 9 hrs
S: 5 hrs
G2: 3 hrs
Mitotic Phase: 1-2 hrs
49
Chromosomes are at their greatest elongation and are
NOT VISIBLE as discrete structures under the light
microscope during the _________
Interphase
50
during _____, chromosomes begin to coil, thus, it becomes more condensed, and it begins to become visible as discrete
structures under a LM
prophase
51
EXPLAIN PROPHASE:
1. 4 daughter chromatids (x structures) pair up forming 2 pairs (each daughter chromatids have 2 sister chromatids)
2. Once paired, nuclear membrane dissolves.
3. Spindle fibers (containing microtubules) moves to opposite poles between centrosomes.
52
Is a short period between prophase and metaphase
during which the nuclear membrane disappears and the
spindle fibers begin to appear
PROMETAPHASE
53
The mitotic spindle is completed. The centrioles divide
and move to opposite poles. The chromosomes line up
on the equatorial plate. Chromosomes reach their
maximum state of contraction during this phase.
METAPHASE
54
Why is the metaphase chromosomes that are traditionally studied in cytogenetics?
Chromosomes reach their maximum state of contraction during this phase
55
What phase?
• The chromosomes line up neatly end-to-end along the
center (equator) of the cell
• The centrioles are now at the opposite poles of the cell
with the mitotic spindle fibers extending from them. So,
the mitotic spindle fibers attach to each of the sister
chromatids
Metaphase
56
• Here, centromeres divide longitudinally and the
| chromatids separate during this stage
Anaphase
57
• Sister chromatids migrate to opposite poles as anaphase
progresses
• The sister chromatids are then pulled apart by the mitotic
spindle which pulls one chromatid to one pole and the
other chromatid to the opposite pole
Anaphase
58
Final stage of mitosis
Telophase
59
• Chromosomes uncoil and become indistinguishable
again. The nuclei reform, and the nuclear membrane is
reconstructed
• At each pole of the cell, a full set of chromosomes gather
together.
• A membrane forms around each set of chromosomes to
create two new nuclei
Telophase
60
Cytoplasmic Division
Cytokinesis
60
Cytoplasmic Division
Cytokinesis
61
PRODUCTS OF MITOSIS:
- 2 genetically identical daughter cells
| - contain complete set of genetic material from parent cell
62
process wherein the cytoplasm of the cell is split in two
Cytokinesis
63
A process involving one duplication of the DNA and two
| cell divisions
Meiosis
64
PROVIDE DEFINITION:
Diploid:
Haploid:
Diploid: 2 sets of chromosomes
Haploid: single set of chromosomes (46-23)
65
PROVIDE DEFINITION:
Meiosis I:
Meiosis II:
Meiosis I: Reductional Division
| Meiosis II: Equational Division
66
Homologue pairs separates during a first round of cell
| division
meiosis I
67
Sister chromatids separate during a second round
meiosis II
68
Each chromosome carefully aligns with its homologue partner so that the two match up at corresponding positions along their full length.
Prophase I
69
Homologue partner are also known as
bivalent chromosomes
70
Process in which homologous chromosomes trade parts
| basically, two chromosomes cross over and exchange a part of their chromosomes
Crossing over
71
Crossing over is helped along by a protein structure called __________ that holds the homologues together.
synaptonemal complex
72
The point where cross-over occurs is called the
Chiasma (plural: chiasmata)
73
The phase in meiosis involving the crossing over of alleles of each gene from the homologous chromosomes (bivalent chromosomes)
Prophase I
74
5 RECOGNIZABLE STAGES OF PROPHASE I:
1. Leptonema
2. Zygonema
3. Pachynema
4. Diplonema
5. Diakinesis
74
5 RECOGNIZABLE STAGES OF PROPHASE I:
1. Leptonema
2. Zygonema
3. Pachynema
4. Diplonema
5. Diakinesis
75
referred to as the thin thread stage
Leptonema
76
- The chromosomes are long and slender with many bead-like structures
- Each chromosome appears as a single structure
chromomere
77
Stage where homologous chromosomes pair to form
| bivalent or tetrad. Synaptonemal complex is formed.
Zygonema
78
Homologous chromosomes appear as long thread-like structures pair locus per locus
Zygotene
79
Pairing is called
synapsis
80
T or F:
The synaptonemal complex can be seen with electron
microscopy
T
81
It's a process from being single to having a pair.
Zygonema
82
What holds the chromosome together during Zygonema?
Synaptonemal complex
83
The chromosomes continue to condense and now appear
| as thicker threads
Pachytene
84
In pachytene, paired homologues from structures called bivalents are sometimes referred to as ________ because they are composed of four chromatids
tetrads
85
What stage of prophase does phenomenon of crossing over occurs?
Pachytene
86
What stage of prophase is this?
- Longitudinal separation of bivalents
- In diplotene, chromosomes continue to shorten and
thicken. The homologous chromosomes begin to repel
each other
Diplonema
87
• There is maximal contraction of bivalents showing a
unique configuration due to repulsion of bivalents
• Chromosomes reach their greatest contraction during this
stage of prophase
• This is the stage where bivalents are distributed
throughout the nucleus
Diakinesis
88
During _________, homologue pairs – not individual chromosomes – line up at the equatorial plate for separation
metaphase I
89
Homologous chromosomes – each containing two
| chromatids move to separate poles
Anaphase I
90
Each of the 2 daughter cells is now in haploid (n) with half the number of chromosomes per nucleus as in meiosis I.
Telophase I
