Recording-2025-03-12T11_44_50.599Z

OverviewStudents have four documents to work on in preparation for an upcoming lab test next week. The content covered includes detailed discussions on Chapter 7, which is mostly completed, and an introduction to Chapter 8 that will begin soon. In addition to these chapters, the students are also exploring various concepts surrounding cellular division.

Cellular Division OverviewMitosisMitosis is the process of somatic cell division (non-sex cells) crucial for growth and tissue repair. The process involves several key steps known as PMAT:

• Prophase: Chromosomes condense and become visible; the nuclear envelope begins to break down.

• Metaphase: Chromosomes align at the cell's equator, and spindle fibers attach to kinetochores on the centromeres.

• Anaphase: Sister chromatids are pulled apart toward opposite poles of the cell.

• Telophase: Two new nuclear membranes begin to form around the separated sets of chromosomes, which begin to de-condense.

Cytokinesis, the final step in cell division, follows mitosis, resulting in two distinct daughter cells. Interphase occurs before mitosis and includes the G1, S, and G2 phases. Each phase has distinct functions:

• G1 phase: The cell grows and synthesizes proteins necessary for DNA replication.

• S phase: This is critical for DNA replication; during this phase, DNA is unwrapped by helicase, which separates the double helix. Adenine (A) pairs with Thymine (T), while Cytosine (C) pairs with Guanine (G) in the DNA structure.

• G2 phase: Further preparation occurs for mitosis, where the cell ensures all DNA has been accurately replicated and the cell is ready to divide.

The discussions also emphasized the importance of understanding the checkpoints in the cell cycle and the role of key proteins in regulating these phases, which can prevent errors during cell division.