ANATOMY

Detailed explanation-1: -Answer and Explanation: The correct answer is (a): cell, tissue, organ, organ systems, organism. All animals are multicellular and cells are the smallest living units. Cells come together to form tissues.

Detailed explanation-2: -Six general levels of the organization listed from smallest to largest are chemical, cellular, tissue, organ, organ system, and organism levels. Chemicals are regarded to be the smallest and lowest unit of organization in a living system, ranging from the smallest atoms to the largest macromolecules.

Detailed explanation-3: -Levels of biological organization from smallest to largest are Atoms, molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biome. Organism: An individual animal, plant, or single-celled life form .

Detailed explanation-4: -Therefore, we can conclude that the order of these structures, from smallest to largest, is cells → tissues → organs → organ systems. An organism is one living thing. An organism may be made of one cell, in which case they are referred to as a unicellular organism.

Detailed explanation-5: -The first and most basic level of organization is the cellular level. A cell is the basic unit of life and the smallest unit capable of reproduction. While cells vary greatly in their structure and function based on the type of organism, all cells have a few things in common.