Yeast is a fungus and needs a supply of energy for its living and growth. Sugar supplies this energy. (Your body also gets much of its energy from sugar and other carbohydrates.). Yeast can use oxygen to release the energy from sugar (like you can) in the process called respiration. So, the more sugar there is, the more active the yeast will be and the faster its growth (up to a certain point-even yeast cannot grow in very strong sugar-such as honey).
Molecules are held together by either covalent bonding or ionic bonding. Several types of non-metal elements exist only as molecules in the environment. For example, hydrogen only exists as hydrogen molecule. A molecule of a compound is made out of two or more elements.
The difference between a polar (water) and nonpolar (ethane) molecule is due to the unequal sharing of electrons within the polar molecule. Nonpolar molecules have electrons equally shared within their covalent bonds.ince carbon can make covalent bonds with another carbon atom, carbon chains and rings that serve as the backbones of organic molecules are possible. Chemical bonds store energy. The C-C covalent bond has 83.1 Kcal (kilocalories) per mole, while the C=C double covalent bond has 147 Kcal/mole.