Question map
Which one of the following statements about life processes in single-celled organisms is not correct?
Explanation
In single-celled organisms, all life processes are carried out within a single cell, and they do not require separate or specialized organs for food uptake [4]. Because the entire surface of a unicellular organism remains in direct contact with the external environment, essential processes like taking in food, exchange of gases (respiration), and removal of wastes (excretion) occur through simple diffusion or the cell surface [2]. Therefore, statement 1 is incorrect as it claims they require separate organs for food uptake. In contrast, multicellular organisms possess specialized tissues and organs because their internal cells are not in direct contact with the environment [3]. Unicellular organisms like amoeba use pseudopodia or specific spots for ingestion, but these are cellular mechanisms, not complex organs.
Sources
- [4] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > 5.2.4 Nutrition in Human Beings > p. 84
- [3] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > 5.5 EXCRETION CRETION > p. 96
- [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > 2.5 Why Is Cell Considered to Be a Basic Unit of Life? > p. 23
- [2] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > 5.1 WHAT ARE LIFE PROCESSES? > p. 80