Mitosis in Whitefish Blastula

Study Notes

Interphase

First and longest phase of the cell cycle, crucial for triggering cell division.
Cells carry out normal metabolic activities and grow during this stage.
Microtubule arrays, called asters, extend from centrosomes.
Both DNA and centrioles replicate to prepare for mitosis.

Early Prophase

Marks the beginning of mitosis, characterized by extensive microtubule formation around centrioles.
Chromatin condenses and coils into distinct chromosomes.
Chromatids are joined at the centromere, held together by the cohesin protein complex.
Nucleoli disappear, and the mitotic spindle forms, pushing centrioles to opposite poles.

Late Prophase

Nuclear envelope begins to fragment as the mitotic process progresses.
Spindle microtubules connect to kinetochores, specialized protein-DNA complexes at the chromosome's centromeres.
Non-attached microtubules are referred to as polar microtubules.
Kinetochores pull chromosomes toward the cell’s equatorial center.

Metaphase

Second phase of mitosis where chromosomes align at the cell's equator, forming a metaphase plate.
Centromeres of chromosomes are oriented along the spindle's equatorial plane.
An enzyme, separase, cleaves cohesin, signaling the transition to anaphase.

Anaphase

Third stage of mitosis where sister chromatids are pulled apart towards opposite poles.
This phase is the shortest and most easily identifiable in slides.

Telophase and Cytokinesis

Telophase initiates when chromosomal movement halts, and it essentially reverses prophase events.
The nuclear envelope re-forms from the rough endoplasmic reticulum, while nucleoli reappear.
The cell briefly becomes binucleate as mitosis concludes.
Cytokinesis, the physical division of the cell into two daughter cells, involves the formation of a cleavage furrow, starting in anaphase and continuing through telophase.

Description

Explore the stages of mitosis in Whitefish blastula through this flashcard quiz. Learn about key terms such as Interphase and Early Prophase while understanding the processes involved in cell division. Each card provides concise definitions to help reinforce your knowledge.