a) Unicellular organisms have one – celled body. TRUE (The latin prefix “uni” means “one” and “cella” means “small room”. Hence unicellular means organisms whose body is made up of a single cell for example amoeba, paramoecium are unicellular organisms.
(b) Muscle cells are branched. FALSE (Muscle cells are usually unbranched except for the cardiac muscle cells. Our body constitutes skeletal muscles (cylindrical and unbranched), smooth muscles (spindle shaped and unbranched) and cardiac muscles (cylindrical and branched).
c) The basic living unit of an organism is an organ. FALSE. (The basic living unit of an organism is a cell because body of all living organisms are made up of cells and are capable of performing all the vital functions).
(d) Amoeba has irregular shape. TRUE (cells have a definite shape as they perform a definite function, however amoeba does not have a fixed shape and thus we can say amoeba has irregular shape).
Final Answer
Unicellular organisms have one celled body TRUE
Muscle cells are branched FALSE
The basic unit of an organism is an organ FALSE
Amoeba has irregular shape TRUE