Problem 7 - Biology Concepts and Applications

Question

After mitosis, the chromosome number of a daughter cell is _______ the parent cell's. a. the same as b. one-half c. rearranged compared to d. doubled compared to

Step-by-Step Solution

Answer

a. the same as

Step 1: Understanding Mitosis

Mitosis is a process of cell division that results in two daughter cells, each having the same number and kind of chromosomes as the parent cell. It ensures that genetic material is duplicated and distributed equally.

Step 2: Chromosome Duplication

Before mitosis begins, the parent cell duplicates its chromosomes during the S phase of the cell cycle, preparing the genetic material for division. This doubling ensures each new cell receives an identical set of chromosomes.

Step 3: Cell Division in Mitosis

During mitosis, the duplicated chromosomes are separated and distributed into two daughter cells. This process involves several stages: prophase, metaphase, anaphase, and telophase, leading to the division of the nucleus and the cell cytoplasm.

Step 4: Outcome of Mitosis

The result of mitosis is two genetically identical daughter cells. Each daughter cell has the same chromosome number as the original parent cell, maintaining genetic consistency across cell generations.

Key Concepts

Chromosome Number

In the context of mitosis, preserving the chromosome number is crucial. Chromosomes are structures within the cell that hold our DNA. To sustain biological functions and inheritance of traits, the chromosome number in daughter cells post-mitosis remains unchanged compared to the parent cell. This ensures that all genetic material is adequately copied and preserved at each division.

Mitosis is organized such that:

• Each parent cell's chromosomes are duplicated before the division process begins.
• During division, this ensures that each of the two resulting daughter cells receives an exact copy of these chromosomes.

This copying accuracy keeps the cell's genetic information consistent, essential for proper biological growth, repair, and reproduction.

Cell Division

Cell division through the process of mitosis is a sophisticated and coordinated event. The primary goal is to split a single cell into two identical daughter cells. This involves duplicating and equal distribution of the cell's genetic material.

The mitosis process can be divided into distinct phases:

• Prophase: Chromosomes condense, becoming more visible; the mitotic spindle forms.
• Metaphase: Chromosomes line up at the cell's equator.
• Anaphase: Sister chromatids (the duplicated chromosomes) are pulled apart to opposite poles of the cell.
• Telophase: The cell begins to split, and nuclear membranes start to reform around each new set of chromosomes.

Following these stages, cytokinesis occurs, which is the final step where the cell's cytoplasm divides, resulting in two separate cells.

Genetic Material Duplication

Before a cell enters into mitosis, it must first duplicate its genetic material. This process mainly occurs during the S phase of the cell cycle, preceding mitosis. During this phase, each chromosome in the cell's nucleus is copied to form two sister chromatids.

• Each pair of chromatids is joined at a region called the centromere.
• This duplication ensures that each daughter cell receives an exact copy of the genetic material.

This precise replication of genetic information is vital because it maintains genetic stability across generations of cells. During mitosis, these duplicated chromosomes are meticulously aligned and then segregated to ensure each new daughter cell inherits a complete set of genetic instructions just like the parent cell.