The document discusses key concepts in cell biology including the cell theory, exceptions to the cell theory, differentiation, and emergent properties. It states that the cell theory establishes that all living things are made of cells, cells are the basic unit of life, and cells come from pre-existing cells. However, there are some exceptions like mitochondria, chloroplasts, viruses, skeletal muscle, giant algae, and aseptate fungi. It also explains that differentiation allows cells to specialize their functions, giving multicellular organisms an advantage through division of labor. Finally, it defines emergent properties as new characteristics that arise when biological units combine that cannot be predicted from knowledge of individual components alone, like how life itself is an emer

1. Topic 1: Cells
Exceptions to Cell Theory &
Differentiation
Mr Goodwin

3. Functions of Life
• All systems classified as “living” must be able
to do the following on their own:
– Reproduce + Pass on genes
– Evolve + Respond + Adapt to their changing
environment
– Metabolize nutrients + Excrete Waste
– Grow + Develop over time
– Maintain Homeostasis

5. The Cell Theory
• Once we know something is living, we also
know it must follow the Cell Theory:
– All living things are made of cells.
– Cells are the most basic unit of life.
– Existing cells come from pre-existing cells.

6. Exceptions to Cell Theory
1. Mitochondria & chloroplasts
2. Viruses
Tissues and organisms not made of typical
cells:
1. Skeletal muscle
2. Giant algae
3. Aseptate fungi

7. Past paper question

12. Differentiation
• Cells become specialized for different
functions by the process of differentiation
• Gives an advantage to multicellular organisms
by allowing for a division of labor

13. Emergent properties
• When units of biological material are put together, the
properties of the new material are not always additive, or
equal to the sum of the properties of the components.
Instead, at each level, new properties and rules emerge
that cannot be predicted by observations and full
knowledge of the lower levels. Such properties are called
emergent properties (Novikoff, 1945).
• Life itself is an example of an emergent property. For
instance, a single-celled bacterium is alive, but if you
separate the macromolecules that combined to create the
bacterium, these units are not alive. Based on our
knowledge of macromolecules, we would not have been
able to predict that they could combine to form a living
organism, nor could we have predicted ALL of the
characteristics of the resulting bacterium.