Proteins 2 Flashcards
<p>Give some examples of modified types of proteins?</p>
<p>Glycoproteins</p>
<p>Lipoproteins</p>
<p>Metalloproteins</p>
<p>What are glycoproteins?</p>
<p>Compound composed of protein and carbohydrates</p>
<p>How to glycoproteins occur?</p>
<p>From a post-translational modificaiton where a sugar molecule binds via an amino acid in the protein</p>
<p>What are some of the roles of glycoproteins?</p>
<p>Protein stabalisation</p>
<p>Affect solubility</p>
<p>Protein orientation</p>
<p>Signalling</p>
<p>Cell recognition</p>
<p>What is the process of forming a glycoprotein called?</p>
<p>Glycosylation</p>
<p>Where does glycosylation occur?</p>
<p>The endoplasmic reticulum and the golgi apparatus</p>
<p>What are some examples of glycoproteins?</p>
<p>Immunoglobulins</p>
<p>Blood group determinants</p>
<p>What are lipoproteins?</p>
<p>Proteins and lipids bonded together</p>
<p>What is the function of lipid proteins?</p>
<p>Transport insoluble fat and cholesterol in the blood</p>
<p>What are examples of lipoproteins?</p>
<p>High density lipoproteins (HDL)</p>
<p>Low density lipoproteins (LDL)</p>
<p>What are metalloproteins?</p>
<p>Protein molecules with a bound metal ion</p>
<p>What are some examples of metalloproteins?</p>
<p>Enzymes</p>
<p>Storage</p>
<p>Signilling</p>
<p>Transport</p>
<p>What are the three structures of proteins?</p>
<p>Globular (varied function)</p>
<p>Fibrous (structural function)</p>
<p>Membranous (associated with cell or orangelle membrane)</p>
<p>What are some examples of globular proteins?</p>
<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>
<p>What are some examples of fibrous proteins?</p>
<p>Bone matrices</p>
<p>Muscle fibres</p>
<p>Tendons</p>
<p>Connective tissue</p>
<p>What are some examples of membranous proteins?</p>
<p>Relay signal</p>
<p>Membrane transporter</p>
<p>Membrane enzyme</p>
<p>Cell adhesion molecule</p>
<p>What is a specific example of a globular protein?</p>
<p>Haemoglobin</p>
<p>How does haemoglobin operate?</p>
<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>
<p>What does the binding of O2do to the shape of haemoglobin?</p>
<p>Changes its conformaiton which allows for more O2to bind easier</p>
<p>What is cooperative binding?</p>
<p>When a molecules binds to a protein and makes it easier for other molecules to bind</p>
<p>What is a specific example of a fibrous protein?</p>
<p>Collagen</p>
<p>What is the structure of collagen?</p>
<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>
<p>What happens when collagen interacts with each other?</p>
<p>They form fibriles and increase strength</p>
<p>What kind of receptors are present in all cells and what do they allow?</p>
<p>LDL receptors</p>
<p>They allow the internalisation of LDL which is then broken down in lysosomes</p>
<p>What are 5 possible classes of LDL receptormutations?</p>
<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>
