Cells Memebran

Question 1

What’s the structure of the plasma membrane?

Answer 1

The plasma membran is made up of bilateral phospholipids, but there are also some proteins, carbohydrates embedded

Question 2

How does the structure of phospholipids explains the structure of plasma membrane and allows the fonctions of it?

Answer 2

The plasma membran contains bilayer phospholipids. Their hydrophilic heads are in contact with the aqueous fluid, insid and outside the cell, whereas the hydrophobic ends is between the two surfaces. This structure allows the cell to control what coming in and out of it. Some molecules might need proteins, produced by the cell itself, to get through this membran. Others molecules follow their con gradient which is controlled by the cell.

Question 3

What s the fonction of organelle and cell membran?

Answer 3

They control what’s the coming in out of cell. Helps the cell to keep constant internal constancy.

Question 4

How do sub moved in and out of the cell? Telle the different processes and compare them.

Answer 4

• small uncharged sub -> diffusion-> follows the con gradient
• small charged sub-> facilitated diffusion-> follows con gradient but helped by a protein that act like a tunnel-> not expelled by the hydrophobic interior of the cell
• osmosis for water- membrane is perméable to water but it is polar so can’t get through the phobic part of the membrane-> water is moved from area where solute con is highto where it low til grandirent =0
  
  • isotonic solution
    
    • hypotonic solution > solute con outside cell-> ++ water inside cell
    • hypertonic solution opposit
• Active transport- small sub- move them against their con gradient- energy - protein oxydize ATP to get the required energy to pomp the molecule ex K+ or Na-
• Endocytosis and exocytosis - large molecules or bacterias ex Macrophage- vessicules absorb the molecule endocytosis or vessicules fuse with the membran to release large sub exo
  Energy required

Question 5

Compare eukariotic and prokaryotic celles

Answer 5

Diff pro are unicellular organism which have cell wall ( extra layer of protection, hydrate, helpes keep it a shape) no nuclueous, /// eukaryotic have membran-bonded nuclueous mem-bonded sacs (organelles)

Common point 4 
DNA 
Plasma membrane 
Cytoplas
Rhibosoms

Question 6

Compare animal and plant cell

Answer 6

Similar mitonchondria cell organell that generate most of the energy ATP needed for biochem reactions

Diff plants -chloroplast do photosynthesis to generate energy from the light

Question 7

What’s the role of endomembrane system in the production of proteins and membran transport ?

Answer 7

Endomem is a series of interconnected organelles via their membranes
It can be involved in the production of key organelles such as lysosomes ( organelles digest) In the Golgi apparatus lysosomal proteins are formed. Vessicules containing the proteins are formed and go into maturation process. They become highly acidic and can digest other organelles. Help the cell clean up.
Cells can take debris or nutrients from the outside environments destroy it to use it in the lysosome.

Central vacuol in plants are made

ER Endoplasmic reticulum 
In RER (rhibosomes attached to) 

Proteines the synthesised in the RER. They end up —embedded in the membrane—inside the RER—membran pinches off with the protein inside or embedded to the membran to form vessicules-> vessicules fuse with Golgi -> proteins end up in the Golgi membran or inside of it->protéines are transformed (exocytosis)-> proteines get into plasma membran or outside of it

ER losing membran -> vessicules formed
I-> SER synthesise pholipides to replace vessicules in the membrane

But for plasma membran-> gaining membran Exocytosys (add membran) and endocytosis( taking away membran)