You are here : / / / 6 Reasons Why Your Gums are Bleeding. If you regularly see red when you brush your teeth, it could be cause for concern. Here's why your gums are bleeding ' and what to do about it. Jackie Middleton.
Between 1856 and 1863 Mendel cultivated and tested some 29,000 pea plants (Pisum sativum). This study showed that one in four pea plants had purebred recessive alleles, two out of four were hybrid and one out of four were purebred dominant.
Concept 1: Mendel was an Austrian monk who discovered the laws of geneTcs in the 1860's. His cross-bred pea plants to see how traits were passed from generaTon to generaTon. For example, he bred a tall pea plants with a short one, and found that all the oÂ±spring (called the First Filial (F1) generaTon) were tall.