Anaphase

Biology

1. Fundamental Concepts

Definition: Anaphase is a stage in the cell cycle where sister chromatids are separated and pulled towards opposite poles of the cell.
Key Events: The cohesion between sister chromatids breaks down, allowing them to move apart.
Chromosome Movement: Chromosomes are moved by microtubules attached to their kinetochores.

2. Key Concepts

Basic Rule: $${\text{During anaphase, sister chromatids separate and move towards opposite poles}}$$

DNA Content: $${\text{Each pole receives an identical set of chromosomes}}$$

Application: $${\text{Understanding anaphase is crucial for studying genetic inheritance and cell division errors}}$$

3. Examples

Example 1 (Basic)

Problem: If a cell has 46 chromosomes at the start of mitosis, how many chromosomes will be at each pole after anaphase?

Step-by-Step Solution:

Understand that during anaphase, sister chromatids separate.
Since there are 46 chromosomes initially, they will split into two sets of 46.
Therefore, each pole will have $$\frac{{46}}{{2}} = 23$$ chromosomes.

Validation: Initial count: 46; After separation: 23 + 23 = 46 ✓

Example 2 (Intermediate)

Problem: A cell with 92 chromatids enters anaphase. How many chromosomes will be at each pole after anaphase?

Step-by-Step Solution:

Recognize that each chromosome consists of two chromatids.
Calculate the number of chromosomes: $$\frac{{92}}{{2}} = 46$$.
During anaphase, these 46 chromosomes will split into two equal sets.
Thus, each pole will have $$\frac{{46}}{{2}} = 23$$ chromosomes.

Validation: Initial chromatids: 92; Chromosomes: 46; After separation: 23 + 23 = 46 ✓

4. Problem-Solving Techniques

Visual Strategy: Use diagrams to represent chromosomes and their movement during anaphase.
Error-Proofing: Always double-check the initial number of chromosomes or chromatids before calculating.
Concept Reinforcement: Relate anaphase to other stages of the cell cycle to understand its significance.