What is the difference between autosomes and sex chromosomes?

Autosomes are chromosomes that determine the body's general traits, while sex chromosomes determine an individual's sex.

Autosomes and sex chromosomes are two types of chromosomes found in the cells of living organisms. They both play crucial roles in genetic inheritance and the development of an organism, but they have different functions and characteristics.

Autosomes are the chromosomes that contain genes for our general body characteristics, such as eye colour, hair colour, and height. In humans, there are 22 pairs of autosomes, making up 44 of the 46 total chromosomes. Each pair of autosomes in a cell has the same structure and carries the same genes, one from each parent. These genes can have different versions, or alleles, which is why offspring can have a mix of traits from both parents.

Sex chromosomes, on the other hand, are the chromosomes that determine the sex of an individual. In humans, there is one pair of sex chromosomes, making up the remaining two of the 46 total chromosomes. The two types of sex chromosomes are X and Y. Females have two X chromosomes (XX), while males have one X and one Y chromosome (XY). The Y chromosome carries the SRY gene, which triggers male development.

Unlike autosomes, sex chromosomes do not always come in identical pairs. This is because the X and Y chromosomes have different sizes and different sets of genes. The X chromosome is larger and contains many more genes than the Y chromosome. This difference is the reason why certain traits and genetic disorders are sex-linked, meaning they are associated with the genes found on the sex chromosomes.

IB Biology Tutor Summary: In summary, autosomes are 22 pairs of chromosomes that dictate general body traits like eye and hair colour. Sex chromosomes, comprising 1 pair in humans, determine gender, with females having XX and males XY. The Y chromosome carries a gene essential for male development. Unlike autosomes, sex chromosomes can differ in pairs, impacting certain traits and genetic conditions linked to gender.