CELL MEMBRANE TRANSPORT
1. The dialysis tubing used in this experiment represents a cellular membrane. Knowing
this, discuss what properties of the cell membrane were tested during this experiment.
Specifically examine what molecule(s) crossed the membrane and what molecule(s) were
prevented from crossing the membrane and why.
2. Survival courses train individuals that when stranded at sea they should never drink the
salt water. Why is the intake of salt water detrimental to health and how does this relate
to your laboratory experience with osmosis?
3. Freshwater protozoa, which are unicellular organisms, have a greater concentration of
salt inside them than does the surrounding water. Does water diffuse into or out of the
protozoa? Explain why this would happen and what protective measures the protozoa
should take to prevent injury or death.
- Question 2:
- Question 1:
- Question 3:
Bio 105- Please answer 50-60 words each.
1.Human Exponential Population Growth
Prior to 1950, the death rate was high, which kept the numbers of humans from increasing rapidly. In the 19th Century, the agricultural revolution increased food production. The industrial revolution improved methods of transporting food and other good. In the 20th Century, advances in medicine, sanitation and nutrition have decreased the death rates further. These factors combined to produce the rapid growth of the human population in the 20th century. Explain 4 factors (inventions or public health measures) that decrease the death rates of infants and small children that lead to our exponential population growth.
2.Population Growth Problem
“The world is characterized by scarcity and competition for limited resources. Further growth of either human populations or standard of living will be disastrous.” Think about this statement and decide if you agree or disagree with it and why. Note the either clause in the statement.
What would be worse population growth or increases in the average standard of living?