Features of cells that would be considered a “trend” Cell membrane separating the cell contents from the outside Genetic material storing instructions for the cell Energy release systems to power the cell’s activities Machinery for creating proteins Cytoplasm with enzymes to catalyze metabolism

Why are “trends” useful in the study of biology? Trends lead to the development of a theory Trends allow us to make predictions for what we expect to observe If you knew that there was a cell in the mystery box, would you be able to predict what features would be present?

Discrepancies do not necessarily disprove a theory. For example, the cell discrepancies we discussed are just not “typical” cells. It is unlikely that the cell theory will ever be discarded.

1.1.NOS1 Looking for trends and discrepancies - although most organisms conform to cell theory, there are exceptions. Define “trend” and “discrepancy.” Explain why “trends and discrepancies” are useful in scientific study. List features of cells that would be considered a “trend”. List examples of cell types or organisms that are “discrepancies” to the cell theory.

1.1.A1 Questioning the cell theory using atypical examples, including striated muscle, giant algae and aseptate fungal hyphae. Describe features of striated muscle fibers that make them an atypical example cell. Describe features of aseptate fungal hyphae that make them an atypical example cell. Describe features of giant algae that make them an atypical example cell.