Transcript central.d127.org

Kubu Information
 Kubus are small, cube-shaped,
unicellular organisms.
 When they’re hungry, they turn pink
 You have only ten minutes to feed three
different sizes of Kubu before they
starve.
 Parts of each Kubu that are properly
nourished will return to the neutral
color.
 To determine how effective this feeding
process is we will have to sacrifice
some Kubus.
Procedure
 Place your assigned Kubus into
the plastic cup and bathe them in
Liquid Food.
 Complete Data Table 1
 Remove the cubes and slice in
half.
 Measure the depth of food
penetration and complete Data
Table 2.
 Determine the percentage of
each Kubu fed.
Analysis
1.
Use your class data to explain how the rate of diffusion is
affected by cell size.
2.
Which Kubu was fed to the greatest extent (highest % fed)?
3.
Graph the SA/V ratio versus the percent fed.
4.
What would be the SA/V ratio and the percent fed for a Kubu with
a length of 4? Explain how you reached these answers.
5.
If a human cell is .001cm in diameter, how long would it take for
materials to reach the deepest parts of the cell at the same rate
seen in this lab? Show your work.
6.
For any cell alive today, what problems might exist if it has only a
low percentage of its volume reached by absorbed materials?