This document summarizes four required labs for a class: 1) A diffusion through a membrane lab using a dialysis bag to demonstrate selective permeability and diffusion of glucose and starch. 2) A biodiversity lab covering genetic coding, molecular similarities between organisms, and the importance of biodiversity. 3) A lab on making connections measuring pulse rates under stress. 4) A lab on Darwin's finches demonstrating adaptive radiation and natural selection on islands through variation in beak shapes.

1. Required Labs Review
Lab 1 Diffusion Through A Membrane
Concepts You Must Know
a) The dialysis bag is the "cell"
b) Diffusion moves material from high to low concentration..spending no
energy
c) Only small molecules will go through the membrane(selective permeable)...
(starch can not)
d) Benedict's solution tests for sugar...heat it and it turns red (positive for
glucose)
e) Iodine tests for starch...turns blue / black in starch
f) Water is used as a control for the indicators
g) The diffusion of water is osmosis
Procedure
a) Make dialysis tube "cell"....tube represents cell membrane
b) Pour glucose solution and starch solution into the tube...seal the ends
c) Place "cell" in beaker of pure water until "cell" is covered
d) Add Iodine (starch indicator) to water in beaker (outside the cell)
e) After 20 minute the "cell" should turn blue/black indicating that the iodine
diffused into the "cell" and detected the presence of starch inside the "cell'
f) Test the water outside the "cell" for glucose...Benedict's will turn orange/red
after heating if it detects the presence of glucose outside the "cell'.
(Did glucose diffused out of the "cell" after 20 minutes ?)

2. g) Starch WILL NOT diffuse out of the cell because it is too big and not
permeable
Observations and Questions
WHY MUST WE DIGEST STARCH BEFORE WE CAN USE IT FOR
ENERGY ?
WHY DO YOU THINK THEY SERVE FREE SALTY PRETZELS IN A
BAR ?
DESCRIBE THE MOVEMENT OF ALL 4 SOLUTIONS IN THIS
EXPERIMENT:
1) WHERE DID THE IODINE GO?
2) WHERE DID THE STARCH GO?
3) WHERE DID THE BENEDICT'S SOLUTION GO?
4) WHERE DID THE GLUCOSE GO?
WHY ARE INTRAVENOUS INJECTIONS ISOTONIC ?
WHAT HAPPENS TO A CELL IN A HYPERTONIC SOLUTION (SALTY) ?
(note the shrinkage)
WHAT HAPPENS TO A CELL IN A HYPOTONIC SOLUTION (WATERY)
?
5) WHAT TYPE OF WATER IS MORE DAMAGING TO THE CELLS IN
THE LUNGS ? ..SALT OR FRESH...WHY?
Lab 2 Biodiversity
Concepts You Must Know:
a) Organisms with similar structural or molecular similarities may be related.
b) In order for a species to be successful and survive it must contain variety
(diversity)

3. c) Proteins and enzymes are produced as a result of an organism's genetic code
sequence.
The DNA code is transmitted from DNA-------> mRNA -------->tRNA
d) Base pair codes are as follows:
A----
DNA "always tired"
T
C---- "constantly
G grumpy"
m and t A-----
"always ugly"
RNA U
C----- "constantly
G grumpy"
e) Amino acids are the building blocks of proteins
f) Molecular similarities are the most important evidence of closely related
organisms.
g) Organisms evolve much like the branches growing on a tree
h) Biodiversity ensures genetic variation.
i) Biodiversity increases stability in an ecosystem.
j) Endangered species hold medicinal, agricultural. ecological, commercial and
aesthetic value.
k) They must be protected for future generations.
1) WHAT ACTIVITIES BY HUMAN COULD ENDANGER PLANTS ?
2) WHY IS Botana curus SO IMPORTANT ? HOW CAN IT BE SAVED ?
3) WHY WOULD YOU NOT WANT TO SAVE Botana curus FROM
EXTINCTION ?

4. Lab 3 Making Connections
Concepts You Must Know:
a) Resting pulse rates vary with individuals.
b) By collecting data scientists can help to answer questions they have
proposed.
c) Pulse rate increases under physical or emotional stress.
d) Increase in activity produces muscle fatigue.
e) Increase in circulation decreases muscle fatigue
f) Increase in activity/circulation causes an increase in respiration
g) Use the Scientific Method to solve a problem that you have postulated.
Lab 4 Darwin's Finches Adaptive Radiation
Concepts You Must Know:
a) Certain adaptations give some organisms an advantage to survive.
b) The environment "naturally selects" which organisms are best suited (fittest)
to survive and reproduce.
In this lab the type of seed was the selecting agent in the island environment.
c) Those organisms that survive and reproduce pass these favorable traits on to
the next generation. This gives their offspring an advantage to survive.
d) Competition for resources (food, water, mates and territory) stimulates the
struggle for survival.
1) WHAT OTHER TRAITS WILL HELP FINCHES SURVIVE BESIDES
THE SHAPE OF THEIR BEAKS ?

5. 2) WHAT TYPE OF BEAK WILL BE A FAVORABLE ADAPTATION TO
CATCH MICE ON THE ISLAND ?
3) DEFINE THE FOLLOWING TERMS
VARIATION, COMPETITION, STRUGGLE FOR
SURVIVAL,ADAPTATION, ENVIRONMENT AND SELECTING AGENT