a.
Which macromolecule listed above do you predict would be the most likely candidate to be able to diffuse through the semipermeable membrane? Which macromolecule(s) actually diffused through based on the class results? (1 pt)
We predict that glucose is most likely to diffuse through the semipermeable membrane. Based on the class results, it was seen through the tests of the solutions that the protein
did not pass through the membrane, however reducing sugars (includes glucose but not starch) were able to pass through. Starch was not present either according to the iodine tests. Therefore, the only macromolecule that actually diffused through was glucose.
b.
Why? Consider looking up the molecular structures for each of the macromolecules. (1 pt)
The semipermeable membrane allows small molecules to pass through, however larger ones cannot. In this case, starch is a large monosaccharide and albumen is a large protein, therefore they cannot pass through the membrane. On the other hand, glucose is a small monomer that can pass through the semipermeable membrane.
4.
On Canvas and in your digital lab manual, there are descriptions of macromolecule tests that you will become familiar with over the next several weeks. Write an operational definition
using the following macromolecule tests. The first one has been completed for you. Doing a good job on these operational definitions this week will help you write a
better grant proposal in the assignments coming up in the next few weeks. (4 pts total, 1
pt each)
a.
Burn test: Our operational definition for being organic is whether it burns or not. If the substance burns and its mass changes as a result, then it is organic. If it does not burn at all, then it is inorganic.
b.
Biurett’s test: Our operational definition of whether protein is present depends on whether the solution turns a pale blue or a pale violet. If the solution turns a pale violet, then protein is present. If the solution turns a pale blue, then protein is not present. c.
Benedict’s test: Our operational definition of whether or not reducing sugars are present is if the solution turns yellow, green, or brick red, then reducing sugars are present. If the solution stays blue, then there are no reducing sugars present.
More specifically, if the solution is green or yellow, then there is a small amount of reducing sugars present. If the solution turns brick red, then there are high amounts of reducing sugars present. This works only for reducing sugars, ie glucose, not sucrose. d.
Iodine test: Our operational definition of whether or not starch is present is the color change between dark blue/back and dark yellow or red. If the soltion stays yellow/red there is no starch present. If the solution turns dark blue or black, then starch is present.
