DRAW IT Draw one eukaryotic chromosome as it would appear during interphase, during each of the stages of mitosis, and during cytokinesis. Also draw and label the nuclear envelope and any microtubules attached to the chromosome(s).

Verified step by step guidance

1. Step 1: Begin by drawing a eukaryotic chromosome during interphase. During this phase, the chromosome is not visible as a distinct entity because it is in the form of chromatin, a less condensed form of DNA. Label the nuclear envelope surrounding the chromatin.
2. Step 2: Next, draw the chromosome during prophase of mitosis. The chromatin condenses into visible chromosomes, each consisting of two sister chromatids joined at the centromere. Draw and label the nuclear envelope, which begins to disintegrate, and the spindle fibers (microtubules) that start to form.
3. Step 3: Illustrate the chromosome during metaphase. The chromosomes align at the metaphase plate (the cell's equatorial plane). Draw and label the spindle fibers attached to the centromeres of the chromosomes, and note that the nuclear envelope is no longer visible.
4. Step 4: Proceed to draw the chromosome during anaphase. The sister chromatids are pulled apart by the spindle fibers towards opposite poles of the cell. Label the separated chromatids and the spindle fibers.
5. Step 5: Finally, depict the chromosome during telophase and cytokinesis. The chromatids reach the poles and begin to de-condense back into chromatin. Draw and label the re-forming nuclear envelopes around each set of chromatin and the cleavage furrow that indicates the beginning of cytokinesis, where the cell divides into two daughter cells.

Key Concepts

Eukaryotic Chromosome Structure

Eukaryotic chromosomes are composed of chromatin, which is a complex of DNA and proteins. During interphase, chromosomes are in a relaxed state, making them less visible under a microscope. Each chromosome consists of two sister chromatids joined at the centromere, which becomes prominent during mitosis. Understanding this structure is crucial for accurately depicting chromosomes in different phases.

Mitosis Stages

Mitosis is divided into several stages: prophase, metaphase, anaphase, and telophase. During prophase, chromosomes condense and become visible, while the nuclear envelope begins to break down. In metaphase, chromosomes align at the cell's equatorial plane, and during anaphase, sister chromatids are pulled apart. Telophase involves the reformation of the nuclear envelope around each set of chromosomes, leading to cytokinesis, where the cell divides.

Microtubules and the Mitotic Spindle

Microtubules are dynamic structures that form the mitotic spindle, essential for chromosome movement during mitosis. They attach to chromosomes at the kinetochores, located at the centromeres, facilitating the separation of sister chromatids. Understanding the role of microtubules is vital for illustrating how chromosomes are organized and moved during cell division, particularly in the context of mitosis and cytokinesis.