Chromosomes and DNA
Chromosomes carry genetic information in a molecule called DNA.
A type of cell division called mitosis ensures that when a cell divides each new cell produced has the same genetic information.
DNADeoxyribonucleic acid. The material inside the nucleus of cells, carrying the genetic information of a living being. exists in a cell's nucleus within structures called chromosomeThe structure made of DNA that codes for all the characteristics of an organism.. Each section of a chromosome that contains the code for the production of a particular protein is called a geneThe basic unit of genetic material inherited from our parents. A gene is a section of DNA which controls part of a cell's chemistry - particularly protein production..
Each chromosome is made from a single molecule of DNA, but when a cell is ready to divide, the DNA copies itself, then coils and condenses to form the chromosomes that we see in micrographA photograph taken of a microscopical image..
Each human body cell contains 46 chromosomes. These can be arranged into 23 pairs.
Each chromosome in a pair carries the same types of genes. The 23rd pair are the sex chromosomes:
- In females, the two chromosomes are identical in shape. There are two X chromosomes. Females are referred to as XX.
- In males, one of the chromosomes is a different in shape. There is an X and also a Y chromosome. Males are referred to as XY
Learn more about DNA and the genome with Dr Alex Lathbridge.
Listen to the full series on 成人快手 Sounds.