Genetics |
Mind Maps |
Genetics is the study of heredity, or how certain features pass from parents to their offspring.
Offspring are not usually exactly the same as their parents. For example, their eye colour or height could be different. Genes are the basic units of heredity. Genes are located inside cells. Threadlike structures called chromosomes carry the genes. Chromosomes are made up of DNA. Genes are short sections of DNA. In human beings most cells have 23 pairs of chromosomes, or 46 in total. The sex cells (gametes), sperm cells and egg cells have one set of 23 chromosomes. In the 1850s Gregor Mendel studied pea plants in his garden. He discovered rules for how traits passed from one generation of pea plants to the next. In 1900 scientists began to explain the theory of evolution including an English scientist named Charles Darwin. He described how species adapt to their environments and how new species form. |
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