Sunday, 21 January 2018

Trilaminar or Sandwich Model - DAVSON and DANIELL

CELL MEMBRANE- Cell Membrane is a Thin, Elastic, Delicate and Selective permeable membrane found around all kind of cell (Prokaryotic and Eukaryotic cell).
Biochemical estimation reveals that biomembrane is formed of  Lipid(phospholipid) , protein and Carbohydrate.
Davson and Daniell proposed sandwich model
According to this model cell membrane is like a sandwich ,as in sandwich between two bread piece salad is placed. Same thing occurs in cell membrane here phospholipid(bilayer) placed between two layers of protein. Size of protein is 2*20= 40 angestrom
                            Size of phospholipid(bilayer) = 35 angestrom
Thus total width of cell membrane is 75 angestrom. It can vary upto 100 angestrom.
For more detail I'm providing link-https://youtu.be/cO6rBGU5ngo

CBSE BOARD CLASS -12 PHYSICS MOST IMPORTANT QUESTIONS.

Here is a link for class 12 physics most important physics questions - https://youtu.be/AwpPmtC8UJ8