Proteins 2

Question 1

<p>Give some examples of modified types of proteins?</p>

Answer 1

<p>Glycoproteins</p>

<p>Lipoproteins</p>

<p>Metalloproteins</p>

Question 2

<p>What are glycoproteins?</p>

Answer 2

<p>Compound composed of protein and carbohydrates</p>

Question 3

<p>How to glycoproteins occur?</p>

Answer 3

<p>From a post-translational modificaiton where a sugar molecule binds via an amino acid in the protein</p>

Question 4

<p>What are some of the roles of glycoproteins?</p>

Answer 4

<p>Protein stabalisation</p>

<p>Affect solubility</p>

<p>Protein orientation</p>

<p>Signalling</p>

<p>Cell recognition</p>

Question 5

<p>What is the process of forming a glycoprotein called?</p>

Answer 5

<p>Glycosylation</p>

Question 6

<p>Where does glycosylation occur?</p>

Answer 6

<p>The endoplasmic reticulum and the golgi apparatus</p>

Question 7

<p>What are some examples of glycoproteins?</p>

Answer 7

<p>Immunoglobulins</p>

<p>Blood group determinants</p>

Question 8

<p>What are lipoproteins?</p>

Answer 8

<p>Proteins and lipids bonded together</p>

Question 9

<p>What is the function of lipid proteins?</p>

Answer 9

<p>Transport insoluble fat and cholesterol in the blood</p>

Question 10

<p>What are examples of lipoproteins?</p>

Answer 10

<p>High density lipoproteins (HDL)</p>

<p>Low density lipoproteins (LDL)</p>

Question 11

<p>What are metalloproteins?</p>

Answer 11

<p>Protein molecules with a bound metal ion</p>

Question 12

<p>What are some examples of metalloproteins?</p>

Answer 12

<p>Enzymes</p>

<p>Storage</p>

<p>Signilling</p>

<p>Transport</p>

Question 13

<p>What are the three structures of proteins?</p>

Answer 13

<p>Globular (varied function)</p>

<p>Fibrous (structural function)</p>

<p>Membranous (associated with cell or orangelle membrane)</p>

Question 14

<p>What are some examples of globular proteins?</p>

Answer 14

<p>Enzymes</p>

<p>Messengers (hormones)</p>

<p>Transporters</p>

<p>Stack of amino acids</p>

<p>Structural function such as actin or tubulin</p>

Question 15

<p>What are some examples of fibrous proteins?</p>

Answer 15

<p>Bone matrices</p>

<p>Muscle fibres</p>

<p>Tendons</p>

<p>Connective tissue</p>

Question 16

<p>What are some examples of membranous proteins?</p>

Answer 16

<p>Relay signal</p>

<p>Membrane transporter</p>

<p>Membrane enzyme</p>

<p>Cell adhesion molecule</p>

Question 17

<p>What is a specific example of a globular protein?</p>

Answer 17

<p>Haemoglobin</p>

Question 18

<p>How does haemoglobin operate?</p>

Answer 18

<p>Carries O₂</p>

<p>Haem group at the centre of each polypeptide chain binds to a moleucle of O₂</p>

<p>Composed of 4 units, so you can carry 4 molecules of O₂</p>

Question 19

<p>What does the binding of O₂do to the shape of haemoglobin?</p>

Answer 19

<p>Changes its conformaiton which allows for more O₂to bind easier</p>

Question 20

<p>What is cooperative binding?</p>

Answer 20

<p>When a molecules binds to a protein and makes it easier for other molecules to bind</p>

Question 21

<p>What is a specific example of a fibrous protein?</p>

Answer 21

<p>Collagen</p>

Question 22

<p>What is the structure of collagen?</p>

Answer 22

<p>Three polypeptide chains coil around each other</p>

<p>Held together by hydrogen bonds</p>

<p>Composed of repeated units (glycine - x - proline)_n</p>

<p>where x = alanine, hydroxyproline or lysine)</p>

Question 23

<p>What happens when collagen interacts with each other?</p>

Answer 23

<p>They form fibriles and increase strength</p>

Question 24

<p>What kind of receptors are present in all cells and what do they allow?</p>

Answer 24

<p>LDL receptors</p>

<p>They allow the internalisation of LDL which is then broken down in lysosomes</p>

Question 25

<p>What are 5 possible classes of LDL receptormutations?</p>

Answer 25

<ol> <li>Class 1 - no receptor produced</li> <li>Class 2 - receptor never reach the cell surface</li> <li>Class 3 - receptor can't bind to LDL</li> <li>Class 4 - receptors don't internalise on binding</li> <li>Class 5 - receptors don't release LDL</li></ol>