DNA, Genes and Chromosomes – Basic Principles
How it works
DNA (deoxyribonucleic acid) is the molecule that contains the genetic information in almost all living organisms. It consists of two strands that form a double helix. In eukaryotic cells, most of the DNA is organized in chromosomes in the cell nucleus; in addition, there are small amounts of DNA in the mitochondria, and in plants also in chloroplasts. A gene is a section on the DNA that contains the information for a specific protein or trait. Humans normally have 46 chromosomes in their body cells, arranged in pairs. The sequence of the four bases adenine, thymine, guanine and cytosine determines the genetic information.
Genes are sections of DNA that code for specific proteins or traits. Chromosomes carry most of the DNA in the cell nucleus. The sequence of bases in DNA determines the genetic information.
An example
What is a gene?
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50 Exercises
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: Biology. The topic assignment may vary by federal state.