Chromatids: Chromatids are one of the two identical halves of a replicated chromosome. When a cell prepares to divide, each chromosome duplicates itself, and the resulting two identical strands are called chromatids. They are held together by a structure called the centromere.

Chromosomes: Chromosomes are structures found in the nucleus of cells that carry genetic information. They are made up of DNA and proteins. Each chromosome contains many genes, regulatory elements, and other nucleotide sequences. Humans typically have 46 chromosomes, arranged in 23 pairs.

Genes: Genes are segments of DNA that contain instructions for building proteins or performing other tasks in the body. They are the basic units of heredity and determine many of our traits, such as eye color, height, and susceptibility to certain diseases. Genes are organized along chromosomes.

DNA (Deoxyribonucleic Acid): DNA is a molecule that carries the genetic instructions for the development, functioning, growth, and reproduction of all known living organisms. It is composed of two long strands that coil around each other to form a double helix. DNA consists of nucleotides, which are chemical units containing a sugar, a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, or guanine). The sequence of these bases encodes the genetic information.

Together, these components—chromatids, chromosomes, genes, and DNA—play crucial roles in the storage, transmission, and expression of genetic information within cells and across generations in living organisms.