noun. 1  a mutation occurring in a somatic cell, resulting in a change in the morphology or some other aspect of one part of an organism (usually a plant). 2  It may be maintained by vegetative propagation but not by sexual reproduction.oun. 1  a mutation occurring in a somatic cell, resulting in a change in the morphology or some other aspect of one part of an organism (usually a plant). 2  It may be maintained by vegetative propagation but not by sexual reproduction.
Protein has a range of essential functions in the body, including the following: 1  Required for building and repair of body tissues (including muscle). 2  Enzymes, hormones, and many immune molecules are proteins. 3  Essential body processes such as water balancing, nutrient transport, and muscle contractions require protein to function. 4  Protein is a 5  ... P Enzymes, hormones, and many immune molecules are proteins. 2  Essential body processes such as water balancing, nutrient transport, and muscle contractions require protein to function. 3  Protein is a source of energy. 4  Protein helps keep skin, hair, and nails healthy.
Membrane proteins are important for transporting substances across the cell membrane. They can also function as enzymes or receptors. On the extracellular fluid side of a cell membrane, you find carbohydrates. They help a cell to be recognized as a certain type of cell and are important for holding cells together.