BISC 220Lg Lecture Notes - Lecture 8: Transport Protein, Glucose Transporter, Facilitated Diffusion
41 views4 pages
31 Jan 2016
School
Department
Course
Professor
Document Summary
Bisc 220: these processes are not in isolation, most reactions go in two directions, only one is. Favored: passive diffusion, facilitated diffusion, channel proteins: these are membrane proteins that form channels through the plasma membrane. i. ii. iii. Channel proteins are lined with hydrophobic amino acids. The best studied protein channels are the ion channels. There are various mechanisms for controlling the opening and closing of ion channels. Once the channel is opened, millions of ions can rush through it per seconds. Just how fast these ions move and in which direction depends on the concentration gradient. The potassium channel: this is inserted in membranes iv: two types of transport proteins for facilitated diffusion i. ii. iii. iv. Carrier/transport protein: allows transport to be selective, ex. The binding sites of glucose transporters can discriminate between d-glucose (which can be used by cells) and l-glucose (which cannot). Transport/carrier proteins form channels but they also specifically bind the transported substance.
Get access
Grade+
$40 USD/m
Billed monthly
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
10 Verified Answers
Class+
$30 USD/m
Billed monthly
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
7 Verified Answers
Related Documents
Related Questions
Cellular biology answer check. please check if my answers arecorrect or not.
1) The concentration of ions inside a cell is the same as theirconcentration outside of the cell. True or false? (i chose falsesince having equilibrium inside a cell is bad)
2) Membrane transport proteins...
a)...transport membrane potentials between cells |
b) | ...transport membranes from the ER to the Golgi |
c) | ...are made up of phospholipids |
d) | ...transport molecules across membranes |
i chose d
3)The electrochemical gradienttakes into account:
a) | The concentration of solutes on either side of themembrane. |
b) | The overall charge on either side of the membrane. |
c) | Both of these. |
i chose C. (although i am sure that overall charge matters, Iwasn't sure if concentration of solutes are taken account.)
4) If no energywere expended by an animal cell:
a) | Both gradients would be depleted |
b)The K+ gradient would maintain itself. |
c) | None of these |
d) | The Na+ gradient would maintain itself. |
I chose d) mainly because I think Na+ gradient exist in animalcell and not K+ gradient.
5) Which of the following is a true statement aboutactin?
a) | Once actin has polymerized, it never depolymerizes. |
b) | Actin is a transmembrane protein. |
c) | Actin can form branched networks. |
d) | Actin filaments are organized into hollow tubes. |
I chose c. can't explain why.
6)Ion channels:
a) | Form a hydrophobic channel through the membrane |
b) | Have filters that let sugars through |
c) | Are selective for particular ions (only the |