3.4 Diffusion Flashcards

1
Q

Diffusion is the net movement of molecules from a region of…

A

High concentration to a region of lower concentration

Down a concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

No additional energy is need for diffusion so it is described as a…

A

Passive process - group of molecules concentrated together in an area will move about at random - eventually resulting in them being evenly distributed within the area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Diffusion is fastest when there is…

A

A large surface area

A short distance

A large concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Facilitated diffusion is a kind of diffusion in which the proteins in the membrane help…

A

Molecules to diffuse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Some proteins form water-filled pores that span the membrane these allow…

A

Small water-soluble molecules and ions (glucose or amino acids) to pass through

These channels are specific (only let one kind of molecule/ion through)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Another kind of facilitated diffusion uses…

A

Carrier proteins - intrinsic proteins which span the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Carrier proteins, like channel proteins, are specific. When the molecule binds with the protein it…

A

Changes shape

This causes the molecule to be released on the other side of the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Both kinds of facilitated diffusion require…

A

No additional energy, both use only the kinetic energy or the molecules themselves - passive

Both move molecules from a region of high to low concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly