Problem 5 - Biology Today and Tomorrow Without Physiology

Question

A cell with two of each type of chromosome has \(a(n)\) __________ chromosome number. a. diploid b. haploid c. tetraploid d. abnormal

Step-by-Step Solution

Answer

The cell has a diploid chromosome number.

Step 1: Understanding the Terms

First, let's define the key terms. A 'diploid' organism or cell has two complete sets of chromosomes, one from each parent. A 'haploid' cell contains only one complete set of chromosomes. 'Tetraploid' means the cell has four complete sets, and 'abnormal' could imply an irregular number that doesn't fit typical sets.

Step 2: Analyzing the Question

The question states that the cell has two of each type of chromosome. Since 'diploid' by definition means having two sets of chromosomes, each set coming from one parent, this best describes our scenario. 'Haploid' and 'tetraploid' do not match because they involve one and four sets of chromosomes, respectively.

Step 3: Choosing the Correct Answer

With the understanding that two sets correspond to 'diploid', this reflects the typical state for most somatic cells in an organism. Therefore, 'diploid' is the correct choice that matches the description of the cell having two of each type of chromosome.

Key Concepts

Diploid

When you hear the term 'diploid', think of balance and pairs. In biology, a diploid cell contains two complete sets of chromosomes. These sets are often obtained from each parent, ensuring genetic diversity and a stable genetic core for the organism. This chromosome configuration is typical in somatic cells, which constitute most of the organism’s body, like skin, liver, and muscle cells.

• Two sets of chromosomes.
• Contributes to genetic diversity.
• Common in somatic cells.

It's important to know that the diploid state reflects the basic structure of many multicellular organisms. As organisms grow and develop, these diploid cells continuously divide and multiply, maintaining the genetic framework necessary for normal development and function.

Haploid

The concept of 'haploid' might bring to mind simplicity, as these cells are streamlined with only one set of chromosomes. Typically, haploid cells are gametes, such as sperm and egg cells. During sexual reproduction, the merging of two haploid cells restores the diploid state in the resulting offspring. It's a critical mechanism that ensures genetic variability and species survival.

• Only one set of chromosomes.
• Important for sexual reproduction.
• Examples include sperm and egg cells.

This unique genetic setup allows for a fresh blend of genes from two parents, which is why every organism is a unique combination of its ancestors. Understanding haploid cells is essential for grasping the basics of genetics and heredity.

Tetraploid

Tetraploidy involves a more complex arrangement, where cells contain four complete sets of chromosomes. This is not common in human cells but is often found in certain plants and some animal species. For plants, being tetraploid can have evolutionary advantages, such as increased size, resilience, and adaptability.

• Four sets of chromosomes.
• Often found in certain plants.
• Can provide evolutionary benefits.

Tetraploidy can lead to fascinating traits like larger blooms or hardier crop varieties, making it a valuable feature in agriculture and botany. Understanding tetraploid organisms helps us appreciate the diversity and adaptability of life on Earth.