General Biology 1 (Part III) Flashcards
The sequence of stages from one division to the next.
Cell Cycle
It is an orderly progression of events that occur between the time a new cell has arisen from the division of the parent cell to the point when two daughter cells are produced
Cell Cycle
What are the 3 parts of the Cell Cycle?
Interphase
Mitosis
Cytokinesis
The First and longest stage of the Cell Cycle
Interphase
What are the 3 phases of Interphase?
G1 Phase
S Phase
G2 Phase
The cell’s primary growth phase.
G1 Phase
The cell copies its DNA to produce two sister chromatids and replicates its nucleosomes.
S Phase
Involves further cell growth and organization of cellular contents.
G2 Phase
The Period when chromosome divide.
Mitosis
What are the 4 stages of Mitosis?
Prophase
Metaphase
Anaphase
Telophase
During this phase, chromosome appear as long thin intertwined threads but, as this stage continues, the chromosome becomes shorter and thinner.
Prophase
Stars when the chromosome with spindle fibers attached has moved to the equator of the cell.
Metaphase
The centromeres divide, converting each sister chromatid into a chromosome.
Anaphase
The chromosomes have reached the opposite ends of the cell.
Telophase
Takes place toward the end of Mitosis.
Cytokinesis
Formation of a constriction called cleavage furrow at the equator of the cell.
Animal Cytokinesis
The dividing cell forms a similar structure called the cell plate.
Plant Cytokinesis
The ___________ has key checkpoints where feedback from the cell about its condition every checkpoint.
Cell Cycle
What are the 3 Principle Checkpoints where feedback from the cell about its condition every checkpoint:
G1 Checkpoint
G2 Checkpoint
M PHASE
What happen to the G1 Checkpoint?
When cell growth is assessed.
What happen to G2 Checkpoint?
When DNA replication is assessed
What happen to M Checkpoint
ensures that the chromosomes are properly attached to the spindle and will be distributed accurately
What is the Purpose of Mitosis?
To keep the number of chromosomes constant in all of the cell of the body, so that every cell contains identical genetic material.
What is the Purpose of Meiosis
To provide variation in gametes and to keep the number of chromosomes constant generation after generation.
What is the 2 Consecutive Nuclear Divisions
Meiosis I
Meiosis II
What happened at the Interphase of Meiosis
S phase: Chromosomes are duplicated.
The resulting sister chromatids are held together in the centromere.
The centrosomes are also duplicated.
What will happen at Meiosis I, Prophase 1?
the homologous chromosomes pair and form synapsis.
The paired chromosomes are bivalent.
Crossing over occurs.
What will happen at Meiosis I, Metaphase 1
Bivalents align.
What will happen at Meiosis I, Anaphase 1
the homologous chromosomes separate.
What will happen at Meiosis I, Telophase 1
nuclear envelopes reforms forming two daughter cells.
What will happen at Meiosis II, Prophase II?
chromosomes condenses and new set of spindle fibers forms.
What will happen at Meiosis II, Metaphase II?
chromosomes align themselves along the metaphase plate with the help of spindle fibers.
What will happen at Meiosis II, Anaphase II?
the chromatids are pulled apart by the spindle fibers.
What will happen at Meiosis II, Telophase II?
the cell divide forming 4 haploid cells.
How many cells are there in the (Meiosis) Haploid?
23
How many cells are there in the (Mitosis) Diploid?
46
Cell death
Apoptosis
A cell that leaves the Cell Cycle
G0
Does not divide into 2 daughter cells
Neurons
How many chromosomes are in Mitosis?
46
How many chromosomes are in Meiosis?
23
Pair of Homologous Chromosomes
Bivalent
Overlapping 2 chromosomes of Mother and Father cells
Homologous Chromosomes
