Question

How many chromosomes does a human cell have? What are these chromosomes made of? (pp. 50–51)

Short answer

Answer: Human cells have 46 chromosomes, arranged in 23 pairs. These chromosomes are made up of DNA and proteins, with the DNA carrying the genetic information needed for an organism's growth, development, and function.

Step-by-step solution

Determine the number of chromosomes in a human cell

The number of chromosomes in a human cell is 46. These chromosomes exist as 23 pairs, with one chromosome coming from each parent.

Describe the structure of chromosomes

Chromosomes are made up of a complex combination of DNA (deoxyribonucleic acid) and proteins. DNA contains genetic information that controls the traits, development, and functioning of every living organism, while proteins help maintain the structure of the chromosome and regulate gene activity.

Understanding the role of genes

Genes are segments of DNA that code for specific functional units, such as proteins or RNA molecules. They contain instructions needed to build and maintain an organism's cells and pass traits from parents to offspring. Each chromosome carries several genes, and the human genome contains approximately 20,000 to 25,000 protein-coding genes. In summary, human cells have 46 chromosomes, arranged in 23 pairs. These chromosomes are made up of DNA and proteins, with the DNA carrying the genes that encode the information needed for an organism's growth, development, and function.