Theme 1 Module 1 & 2 Review lecture

what are some different types of membrane? Are they all equally fluid?

nuclear membrane, mitochondiral membrane, thylokoid membrane
- no they are not equally fluid

What does FRAP stand for?

Fluorcent Recovery After Photobleaching

How does frap happen?

• we take DNA for making a protein from any membranes and then we take DNA that will make a protein fluorescent (extract it from animals that give off fluorescent light, attach DNA for that protein on any other protein) and combine them together and it is expressed in the cell ( it will light up)

• then you use a laster to shoot the lights out and kill them

how does FRAP provide proof for membrane fluidity?

• we use a microscopy technique called fluorescent recovery after photo bleaching

  • use can also label proteins fluorcently in different membranes (like you can label membrane in ER)

(Test) During the FRAP experiment do the fluorescent proteins that are bleached comeback to life?

No! the area starts to brighten up in a fluid membrane becasue the proteins in the surrounding area are moving into that spot becasue its fluid

(test) Based on what we talked about in class what is more fluid? ER? or Nuclear membrane? why?

• Nuclear membrane is not as fluid

  • because the proteins need to stay in the same place all the time especially if you’re relying on transciptions factors going in and out, mRNA moving in and out need to know where things are

How does ions move through a membrane?

• Hydrophilic channels allows ions to be surrounded by water and move through membrane

• proteins can also become chanell that help large or charged studd go through the membrance becasue inside of channels are hydrophili

• water has dipole ( O is slightly negative and H is slighlty postive)

  • any ion in a cell can get surrounded by water and now its in a polar enviornment surrounded by polar molecules

how is many ATP is used in a sodium and potassium pump?

3Na+ out and 2K+ in (1 ATP is broken)

How does plants get energy>

Light reactions
1) photons are captured by choloplasts in the thylokoid membranes

• photons extices electrons to move b/w proteins os that in the end as electron are moving b/w proteins you’re eventually donating enery to NAD+ to be able to make NADPH which is important when its time to make sugar

• thylokoid have bunch of photosystem proteins

Dark reactions

2) in stroma there is a 5 carbon sugar that the enzyme is going ot be able to convert into 2,3 carbon sugars then NADPH comes in, reducing those 2-3 carbon sugars into glucose

Plants and People

1) break down glucose into 2,3 carbon sugars and thats going to be your pyruvate molecules
2) pyruvate go to mitochondrial membrane into the matrix

• pyruvate gets converted into acetyle -coa (then lots of chemical reactions in between) (carbon is given off) then acetyl-CoA goes through krebs cycle and make NADH FADH2

  • NADH and FADH2 when breaking down glucose it is important to make electron carriers because it goes through the inner membrane of the mitochondria so allows the activation of proteins to move protons (into the etc) from the matrix into the inter membrane space of the mitochondria to fuel ATP synthesis (loads protons in. a wheel and shoots them into the matrix and forces ADP and phosphate tgt)