Planarias are flat worms that live freely in freshwater and sometimes in teh logs, soil, plants, or other dump or humid areas. They are from the class of Turbellarians. They have a very good ability in regeneration. They are acoelomerate which means that their body is very solid without any hollows.
They excrete unwanted objects from their body using their excretory system which is consists of series of tubes with length similar to their body length. The flame cells remove excess water through the use of the cilia and pass them to the ducts. At the end of the duct, there exist pores called the nephridiapores.
They usually mate in water and they lay eggs.
Mutations are positive occasionally, beneficial occasionally and omission of information.
Answer: Options 1, 3 and 4.
<u>Explanation:</u>
Mutations are more or less permanent changes. These changes are heritable in the phenotype of an individual. These changes occur because of the alteration in the number, kind or the sequence of nucleotide of the genetic material which is DNA in most of the cases.
Mutations occur at some times in the life of people and they are present in only some cells of the human body. They are not present in all the cells of the human body. These changes can also occur because of environmental factors like ultraviolet radiation from the sun.
Its less energy and longer wavelengths