Living things are highly organized and structured, following a hierarchy. Multicellular organisms have five levels of organization ranging from simplest to most complex. Consider the model. Using the letters, put the levels in order from simplest to most complex.
A. R → Q → P → S
B. Q → R → P → S
C. R → Q → S → P
D. S → P → Q → R
The correct answer is A. R → Q → P → S.
In the hierarchy of organization in multicellular organisms, the levels generally go from the simplest to the most complex as follows:
1. R (Cells) – The basic unit of life.
2. Q (Tissues) – Groups of similar cells that work together.
3. P (Organs) – Structures made of different types of tissues that perform specific functions.
4. S (Organ Systems) – Groups of organs that work together to carry out a particular function.
This order reflects the increasing complexity and specialization of living structures.