How it works
Seven boxes joined by arrows, small to large, with no level of organization labeled. The four levels past the organism are on the levels of organization diagram.
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From cells to organisms with no labels: what each box gives
The picture and the words under it are the clue; the name of the level goes on the dashed tag. Two pairs are easy to swap. One ball ringed by dots is an atom, and three joined balls are a molecule. The stomach alone is an organ; the stomach drawn with the intestines is an organ system.
Anatomy levels of organization under other names
A text may name a level by its adjective: atomic, molecular, cellular, histological for the tissue level, then the organ and organ system levels. A class list that says system or body system means the organ system. Organelle, on lists that have it, falls between molecule and cell and has no box here.
- On the Numbered sheet the cell is 1 and the atom is 6: the numbers do not follow the arrows.
Questions and answers
Is a single-celled organism a cell or an organism?
Both. A living thing made of a single cell is at the cell level and the organism level at once. It has no tissues, so the tissue, organ and organ system tags apply only to many-celled organisms.
What are emergent properties in the levels of organization?
New functions that appear at one level and that the parts from the level below could not carry out alone. Every step up the chart, from atom to organism, brings some.
Which tissues make up the stomach?
Four kinds: muscle, connective, epithelial and nervous tissue. Muscle and connective tissue form its wall, epithelial and connective tissue its lining, and nervous tissue runs through both.