Class Notes (838,457)
Canada (510,890)
York University (35,470)
Biology (2,273)
BIOL 1000 (397)
Lecture 5

Lecture 5 - ER and Golgi.docx

3 Pages
Unlock Document

BIOL 1000
Michael Gadsden

Lecture 5 IN Endoplasmic Reticulum  Basic (general) unit sugars are added onto proteins  and proteins are folded into 3 structures  Leave in vesicles to the Golgi IN the Golgi  Modifications to protein structures and sugar arrangement occurred  Essentially some sugars are removed and others are added on depending on the protein  Poly-peptide (protein) have many sugars added on (oligosaccharide chains)  See sheet  Glycoproteins have the same general order of sugars (as all of them are in the ER)  Sugar chain + protein = glycoproteins  Glycoproteins mostly end up on the cell membranes  See Sheet  The sugars end up outside of the cell and are inside the vesicles  For glycoproteins the sugars help with: o Identification of the cell o EG (liver cells to come together and stick together) o Protects the cell from invasions by pathogens (viruses, bacteria, and other pathogens) o Changes in the environment (i.e. acid, salts)  Outer part of cell and protein o See Sheet o Known as the glycocalyx o The saccharide coat of eukaryotic cells (this is not present in Prokaryotes) o Medical Importance  Transplants (glycoprotein codes!)  One must wash the saccharides off in the glycocalyx  This is so they cannot be recognized by antibodies and killed  Tissue will thus be protected  Another option is to give the person drugs so that the immune system is down, but this is problematic because they are weak (no antibodies)  EVERYONES sugar patterns are different (But aren’t the glycocalyxes the same amongst one species?)  The cells will often begin to produce the transplanted area’s glycoproteins (But won’t the cells begin to reproduce the old glycoprotein?) o Some sugar chains target a polypeptide to a cellular location  I.e. a specific mannose put on a polypeptide in Golgi will indicate that this protein should go to the lysosome  Membrane Fusion o Membranes contain receptors and they get pulled closer and then whatever is inside the membrane enters the Golgi and the two membranes become one o Some will go back to the ER and have membrane fusion into the ER  Note: Essentially only the Lysosome or ER will fuse with the vesicles  Vesicle fusion to the Cell membrane o When something is brought out putting vesicle membrane onto the cell membrane it is called “Exocytosis”  Leads to cell growth o When something is brought IN by forming a vesicle from the cell membrane it is “Endocytosis”
More Less

Related notes for BIOL 1000

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.