cell membrane
1. What is a membrane?
2. Concerning their
permeability how are
membranes classified?
3. What is diffusion?
4. What is meant by
concentration gradient? Is it
correct to refer to
“concentration gradient of
water”?
5. What is the difference
between osmosis and
diffusion?
6. What is osmotic pressure?
7. Can solutions with the same
concentration of different
solutes have different osmotic
pressures?
8. How are solutions classified
according to their comparative
tonicity?
9. Concerning permeability
what type of membrane is the
cell membrane?
10. What are the basic
constituents of the cell
membrane?
11. What are the respective
functions of phospholipids,
proteins and carbohydrates of
the cell membrane?
12. What are differentiations
of the cell membrane?
13. What is the relationship
between concentration
gradient and active and
passive transport?
14. What are the three main
types of passive transport?
15. What is the energy source
used in actve transport
through biological
membranes?
16. What is the difference
between simple and facilitated
diffusion? Facilitated by which
type of molecule does the
term “facilitated” mean?
17. How does the intensity of
simple diffusion vary in
relation to the concentration
gradient of the moved
substance?
18. How does the intensity of
facilitated diffusion vary in
relation to the concentration
of the moved substance? What
is the limiting factor?
19.Without saturation of
transport proteins and under
the same concentration
gradient how can the speed of
simple diffusion be compared
to the speed of facilitated
diffusion?
20. How does facilitated
diffusion present similarities
with enzymatic chemical
reactions?
21. What are some examples
of biological activities in which
osmosis plays an important
role?
22. What do facilitated
diffusion and active transport
have in common? What are
the differences between
them?
23. Which are the molecules
that make possible active
transport through
membranes?
24. How does the sodium potassium pump present in
the cell membrane work?
What is the importance of this
protein for the cell?
25 .What is mass
transportation across the cell
membrane?
26.What arethe two main
types ofendocytosis?
27. How does the plant cell
wall react when it is placed
under hypotonic medium?
28. What is meant by suction
force of the plant cell? Does
the suction force facilitate or
make difficult the entrance of
water into the cell?
29. What is the wall resistance
of plant cells? Does this
resistance facilitate or make
difficult the entrance of water
into the cell?
30. What does the formula
DPD = SF – TP mean?
31. What are the values of
DPD for plant cells under
hypertonic, isotonic and
hypotonic media?
32. What is the formula of the
DPD for withered (shrunken)
plant cells? How is that
situation possible?
33. What is deplasmolysis of
plant cells?
34. Why are salt and sugar
used in the production of dried
meat and dried fruits?