Module 32: Cell Division Flashcards
(23 cards)
What refers to the division of the nucleus in Eukaryotes?
Mitosis & Meiosis
Mitosis occurs in?
Somatic (body) cells
Meiosis occurs in
Germ (sex) cells example sperm & egg cells
What is the difference between Mitosis & Meiosis?
- Mitosis leads to diploid cells that are identical to the parent cell. Also 1 round of nuclear division
- Meiosis leads to haploid cells that are distinct from the parent cell. Also, two rounds of nuclear division.
What is diploid?
2 copies of each of 23 chromosomes =46 chromosomes/ cell
What is haploid?
1 copy of each of 23 chromosomes
What are the three stages of interphase?
- G1-Growth
- S-DNA Synthesis
- G2-Growth organelle replication prepares to divide
What are the three major checkpoints of the cell cycle?
- G1 Checkpoint-
- G2-M Checkpoint
- Metaphase-Anaphase
G1 Checkpoint list?
Before DNA Replication.
- Am I large enough?
- Is there enough energy to divide?
- Have I been signaled to divide?
G2-M Checkpoint list?
Organelles need to be replicated.
1. Is DNA replicated finished?
Metaphase-Anaphase Checkpoint list?
Are ALL chromosomes attached to spindle?
What does it mean to say that a cell has “exited the cell” or entered the G0 phase?
Cell do not proceed toward division
G0 Phase?
G0 occurs AFTER mitosis, in G1 BEFORE S phase. G0- performing normal cellular functions, without preparing to divide.
Prophase
Centrosomes duplicate/ begin moving apart. Chromosomes condense and become visible.
Metaphase
Nucleus vanishes. Chromsomes line up in middle of cell. Centrosomes send out spindle fibers.
Anaphase
Spindle shortens-chromosomes pulled towards opposite poles for cells.
Telophase & Cytokinesis
Nuclei begin to re-form. Chromosomes begins to disappear. Chromatin form 2 identical cells.
Process of the Binary fission
- A parent cell at the beginning of the cell cycle. 2. Chromosomes replication and cell enlargement. 3. Chromosomes division and septation. 4. completion of cell compartments. 5. End of cell division cycle.
Cytokinesis
Process where the cells will split
Cleavage furrow
During cytokinesis in animals, the contractible ring of microfilaments around the equator of the cell.
Cell Plate
The precursor for the new cell wall that forms during cytokinesis in plant cells.
What is the difference between a chromosome and a sister chromatid?
Chromosome- Tightly coiled form of the DNA-protein complex.
Sister Chromatid- One of a pair of chromatin threads; one side of a chromosome X-shape.
How many chromosomes are present in a human cell that is in G1 phase?
46 chromosomes and has two copies of ach gene. Mitosis always has 46 chromosomes
