Question

The products of _____ are _____ cells. a. mitosis, diploid b. meiosis, haploid c. meiosis, diploid d. Both a and b are correct.

Short answer

The products of mitosis are diploid cells and the products of meiosis are haploid cells. Therefore, the correct answer is \(d. \textrm{Both a and b are correct}\).

Step-by-step solution

Understanding Mitosis and Meiosis

Mitosis and meiosis are both processes of cell division. Mitosis is the process where a single cell divides into two identical daughter cells with the same number of chromosomes, while meiosis results in four non-identical daughter cells with half the number of chromosomes.

Understanding Diploid and Haploid Cells

Diploid cells have two complete sets of chromosomes, one from each parent, whereas haploid cells have only one complete set of chromosomes. In humans, most of our cells are diploid, containing 46 chromosomes, while our sex cells (sperm and egg) are haploid, containing 23 chromosomes.

Identify the Process and Cell Type Produced

Now that we understand the differences between mitosis and meiosis, and between diploid and haploid cells, we can determine which option matches the correct process and resulting cell type: a. Mitosis results in diploid cells – this is true because when a cell undergoes mitosis, it creates identical daughter cells with the same number of chromosomes. b. Meiosis results in haploid cells – this is also true because during meiosis, the parent cell divides into four cells with half the number of chromosomes. In humans, meiosis leads to the production of sperm and egg cells, which are haploid.

Select the Correct Answer

Based on our understanding and identification of the correct process and resulting cell type, we can now choose the correct answer option: d. Both a and b are correct. This is the correct answer because mitosis results in diploid cells and meiosis results in haploid cells.

Key concepts

Mitosis and Meiosis

When we talk about the fundamental processes of cellular reproduction, two distinct types come to mind—mitosis and meiosis. Each serves a unique purpose in the lifecycle of cells.

Mitosis is akin to cloning; a single cell duplicates its genetic material and divides into two identical daughter cells, each equipped with an identical set of chromosomes to the parent. This is the process through which our bodies repair tissues, grow, and replace dead cells. One way students often remember this is through the phrase 'I (mitosis) made it myself,' emphasizing that the genetic makeup is the same.

Meiosis, on the other hand, is more about variety and is essential for sexual reproduction. It reduces the chromosome number by half, creating four non-identical daughter cells. These cells, known as gametes (sperm and eggs in humans), are inequivalent to each other and to the original parent cell. A helpful mnemonic is 'Me (meiosis) and my partner,' underscoring the genetic diversity brought in from two different parents.

Diploid Cells

Diploid cells are the cellular cornerstone of most organisms, characterized by having two complete sets of chromosomes, one from each parent. This diploid number is often represented as 2n. For example, in humans, the diploid number is 46—which includes 22 pairs of autosomes and two sex chromosomes.

These cells maintain the organism's genetic information in a robust format, which is vital for sexual reproduction. Following fertilization, when haploid sperm and egg combine, the resulting zygote restores the diploid state, exemplifying the full complement of genetic information.

Significance of Diploidy in Multicellular Organisms

This diploidy is significant because it allows for genetic variation and the stability of complex body plans and organ systems in multicellular organisms. In simpler terms, it's what makes each of us genetically unique while still retaining family traits.

Haploid Cells

Haploid cells, indicated with the notation n, contain one set of chromosomes and are paramount in sexual reproduction because they carry genetic information from parent to offspring. Humans and many other organisms produce haploid cells to ensure that when two gametes merge, the resulting offspring will have the correct diploid number of chromosomes, preventing chromosome number abnormalities.

In human biology, haploid cells are exemplified by the sperm and the egg, each carrying 23 chromosomes. Upon fertilization, these 23 chromosomes from the father pair with 23 chromosomes from the mother, forming a new, genetically distinct diploid individual.

Genetic Diversity through Haploidy

Haploidy plays a crucial role in biodiversity. During meiosis, genetic material is mixed and divided in a way that increases variation, which is key to a population's ability to adapt and evolve. Think of haploid cells as a genetic lottery ticket—each one offers a unique combination of genetic traits that may provide an advantage in survival.