SVHS ADVANCED BIOLOGY
9th edition Tortora
NAME: ___________________
PERIOD:
1 2 3 4 5 6
DIRECTED READING 3.2 – TRANSPORT ACROSS
MEMBRANES
AFTER READING PAGES 51-53- TITLED “TRANSPORT ACROSS THE PLASMA MEMBRANE”:
1. Name and contrast ICF with ECF as to where you find each.
ICF
ECF
2. Extracellular fluid can be found in three different places within the body. List those places
and the names given to the fluid depending on where it is found.
Name
Location
a. ___________________
___________________________________
b. ___________________
___________________________________
c. ___________________
___________________________________
3. Define “concentration gradient” using ICF and ECF as an example.
4. Explain the difference between moving up Vs moving down the concentration gradient.
5. Explain how movement across the plasma membrane by passive processes is different from
active processes. List the passive and active processes below and give an example of a
substance that is transported. (See pages 51-56)
Passive Processes
Ex.
Active Processes
Ex.
a. _______________
__________
a. ________________
_________
b. _______________
__________
b. ________________
_________
c. _______________
__________
c. ________________
_________
AFTER READING “PASSIVE PROCESSES” ON PAGES 51-52
6. Describe the two ways in which molecules move across a membrane using simple diffusion.
a.
b.
7. Why do ions require a integral protein to act as a channel in order to pass through the
membrane?
LOOKING AT THE PICTURE SHOWN TO THE RIGHT:
8. Where is the high concentration regarding
molecules? Cytosol or ECF?
9. Which letter represents Glucose moving through
the membrane?
A
B
C
Name the process?
10 What letter represents diffusion of a lipid
soluble molecule?
Why?
11. Which letter represents K+ Moving through the membrane?
If so why?
Is a protein involved in the process?
12. Describe the difference between “A” and “B/C” regarding membrane structure and how the process functions.
13. What is the difference in process “B” and “C” regarding structure and function?
14. Which process would you think water uses if you know that it is a polar molecule?
Why?