This type of clothing should not be worn for parties, weddings and other formal or ceremonial events. They should not also be worn for work. Various items of clothing such as tee-shirts, denims, khakis, jackets, hoodies, mini-skirts, summer dresses, loafers, sneakers, and sandals are casual wear.
The presence of a lone pair decreases the bond angle between the bonding pair of electrons, due to their high electric charge which causes great repulsion between the electrons. They are also used in the formation of a dative bond.
Base pairs occur when nitrogenous bases make hydrogen bonds with each other. Each base has a specific partner: guanine with cytosine, adenine with thymine (in DNA) or adenine with uracil (in RNA). The hydrogen bonds are weak, allowing DNA to 'unzip'. This lets enzymes replicate the DNA.