Question

A defining property of living beings is

• A. Cellular structure
• B. Internal growth
• C. Organisation
• D. All the above

Answer 1

The Correct Option is D

The correct option is (D): All the above

Answer 2

Explanation:

Cellular Structure:

• The defining characteristic of living organisms is their cellular structure. Living organisms are complex structures formed of one or more cells.
• The living matter from which cells are made is the protoplasm.

Internal growth:

• Growth, defined as the irreversible increase in mass of an organism, is facilitated primarily through cell division.
• In multicellular organisms, such as plants, growth persists throughout their lifespan, sustained by meristematic areas where cell division occurs regularly.
• Conversely, animals experience growth until reaching a certain age, thereafter, cell division primarily serves to replenish lost or worn-out tissue.
• Unicellular organisms similarly grow through cell division, which also functions as a mode of reproduction for them. However, in more complex organisms like higher animals and plants, growth and reproduction are deemed incompatible processes.

Organization-

• Living organisms are organised and are categorised as either multicellular or unicellular.
• Atoms create molecules, which in turn create cell organelles and structures, inside every cell. Similar cells combine to form tissues in multicellular organisms.
• In turn, tissues work together to form organs, which are bodily structures with specific functions.
• Organ systems are composed of interconnected organs.
• Multicellular organisms are made up of more than single cells. For example in humans. The cells in multicellular organisms may be specialized to do different jobs and are organized into tissues, such as connective tissue, epithelial tissue, muscle, and nervous tissue. Unicellular organisms are single celled organisms. All life processes including feeding, digestion, excretion etc occur in one cell. For example: Protozoa, Eschercia Coli, Diatoms.