1 Cell Biology TL Unit Contributors:

Cell Biology TL Unit
Brief Description of the TL Unit
Class Process:
1. What must a tree have to produce apples? Draw a model of an apple tree with all possible parts
labeled.
a. GROUP WORK: groups of 3 or 4
b. Draw a model of an apple tree labeling all possible parts. The model should
illustrate how the parts work together to help the tree produce apples.
The model should have
- Parts labeled
- Functions identified for each of the parts
- Arrows showing how resources ( water, CO 2 , sugar etc. ) are transported
2. Now use the model to help make an apple.
a. GROUP WORK (part 2):
b. Integrate all of the parts and processes of the model together into a logical sequence of
events to make an apple.
c. example: model illustrates water (and nutrient) acquisition by roots, transport of water
through trunk and stems to leaves, diffusion of CO 2 into leaf, photosynthesis with CO 2
and light in leaf, transport of sugar to flower and apple. The model can be more complex,
but this simple model will help them start to integrate processes
3. Assess understanding to this point: “perturb and predict” by having students develop scenarios
where 1) spatial and 2) temporal organization are perturbed effecting function.
a. GROUP WORK: groups of 3 or 4
b. You have an apple tree in your yard. Most years you have more apples than you
can eat. This year there was a drought and it appears that there are only a few
small apples on your tree. The some leaves have turned red and others have fallen
off the tree even though it is only mid August.
- Using your model, describe the processes and parts that might have
reduced apple production?
c. Selected groups present model as instructor builds class consensus model for apple tree.
4. FOCUS—Bring to cell level
a. GROUP WORK: groups of 3 or 4
b. Simultaneously repeat steps 1-3 for a leaf cell and a root cell. The two cells will help
identify differences in function and help connect from the cellular to the organismal
scale.
5. Mini-lecture on one cell organelle as illustration of how students should approach the material
a. Vote to decide which organelle to “uncover” first
b. re-emphasize organization concepts while doing this—connections, processes
FIRST National Meeting 2005 1
Kellogg Biological Station
Unit Description