Glycolysis 2 Flashcards
<p>What are some tissues that completely rely on glycolysis for their energy?</p>
<p>Brain</p>
<p>Nervous system</p>
<p>RBCs</p>
<p>Testes</p>
<p>Embryonic tissue</p>
<p>What happens if we have no more carboyhydrates but need more glucose?</p>
<p>It can be generated from non-carbohydrate molecules in the liver</p>
<p>Why is gluconeogensis not the direct reverse of glycolysis?</p>
<p>Due to the 3 irreversible steps (steps 1, 3 and 10)</p>
<p>What is gluconeogensis?</p>
<p>The generation of glucose from non-carbohydrate substances</p>
<p>How many reactions are used to bypass the irreversible steps of glycolysis?</p>
<p>4</p>
<p>What does the bypassing of the irreversible steps of glycolysis allow?</p>
<p>Gluconeogenesis and glycolysis to be regulated seperately</p>
<p>What irreversible reaction does A and B of gluconeogenesis deal with?</p>
<p>PEP to glycolysis</p>
<p>What is step A?</p>
<p>The conversion of pyruvate to oxaloacetate</p>
<p>What is step B?</p>
<p>The conversion of oxaloacetate to PEP</p>
What do reactions A and B look like?
Bypass Reaction A : pyruvate kinase
<p>What step of glycolysis does reaction C bypass?</p>
<p>F-6-P to F-1,6-bisP</p>
What does reaction C look like?
<p>Why is reaction C not the direct reverse of F-6-P to F-1,6-bisP?</p>
<p>It would require the transfer of a phosphyl group which is energetically unfavourable</p>
<p>What step of glycolysis does reaction D bypass?</p>
<p>Glucose to G-6-P</p>
What does reaction D look like?
<p>Where is G-6-P converted to glucose?</p>
<p>In the lumen of the endoplasmic reticulum</p>
<p>What does the conversion of G-6-P to glucose in the ER require?</p>
<p>G-6-P to be shuttled into the ER and glucose to be shuttled out, an inorganic phosphate is also shuttled out</p>
What does this pump controlling the conversion of G-6-P to glucose look like?
<p>How many points can galactose and fructose enter glycolysis?</p>
<p>Several</p>
<p>What is fructose converted into to enter glycolysis?</p>
<p>Glucose-6-phosphate</p>
<p>What is fructose converted into in adipose tissue to enter glycolysis?</p>
<p>Fructose-6-phosphate</p>
<p>What is fructose in the liver converted into to enter glycolysis?</p>
<p>Glyceraldehyde-3-P (GAP) or dihudroxyacetone-P (DHAP)</p>
<p>Where is most fructose metabolised?</p>
<p>Liver</p>
<p>What pathway does fuctose use to become DHAP or GAP in the liver?</p>
<p>Fructose-1-phosphate</p>
<p>How much ATP does the conversion of fructose to DHAP or GAP use?</p>
<p>1 or 2</p>
What does the conversion of fructose to DHAP or GAP look like?
<p>What is galactose converted to G-1-P through?</p>
<p>UDP-galactose</p>
<p>What are the steps of galactose becoming glucose-6-phosphate to enter glycolysis?</p>
<ol> <li>Galactose comes in and is phosphorylated</li> <li>UDP glucose transfers UDP molecule to galactose</li> <li>Captures electrons by producing NADH</li></ol>
<p>What does the pentose phosphate pathway produce?</p>
<p>NADPH and pentoses (5C) sugars</p>
<p>Where and what is NADPH used for?</p>
<p>Liver (fatty acid synthesis)</p>
<p>Mammary gland (fatty acid synthesis)</p>
<p>Adrenal cortex (steroid synthesis)</p>
<p>RBC (antioxidant)</p>
<p>What are pentoses precursers for?</p>
<p>ATP</p>
<p>RNA</p>
<p>DNA</p>
<p>What are the two stages of the pentose phosphate pathway?</p>
<p>Oxidation (irreversible)</p>
<p>Non oxidation (reversible)</p>
<p>Is the oxidation stage of the pentose phosphate pathway reversible?</p>
<p>No</p>
<p>Is the non oxidation stage of the pentose phospate pathway reversible?</p>
<p>Yes</p>
<p>What happens during the oxidative stage of the pentose phosphate pathway?</p>
<p>Generates NADPH</p>
<p>Converts G-6-P to a pentose phosphate</p>
<p>What happens during the non oxidative stage of the pentose phosphate pathway?</p>
<p>Forms lots of different 3, 4, 5, 6 and 7 carbon sugars</p>
What does the pentose phosphate pathway look like?
<p>What does NADPH link?</p>
<p>Anabolic and catabolic pathways</p>
<p>Are NAD+and NADP+the same?</p>
<p>They are both electron carriers but they are not the same</p>
<p>What are NAD+and NADP+?</p>
<p>Electron carriers</p>
<p>What is NAD+used for?</p>
<p>Metabolism of sugars in glycolysis and the citric acid cycle</p>
<p>What is NADP+used for?</p>
<p>Anabolism to make things like fatty acid</p>
<p>What does breaking down ethanol require?</p>
<p>NAD+</p>
What does the breakdown of ethanol look like?
<p>Why does breaking down lots of ethanol inhibit gluconeogenesis?</p>
<p>Low NAD+to facilitate the reaction as most has bean used to breakdown ethanol</p>
<p>What does a low level of NAD+lead to?</p>
<p>Lacticacidaemia (increase[blood lactate])</p>
<p>Hypoglycaemia (decreased [blood glucose])</p>
<p>What is black water fever?</p>
<p>A difficiency of G-6-P dehydrogenase</p>
<p>What does black water fever cause?</p>
<p>Low RBC NADPH levels</p>
<p>Build up of free radicals and H2O2which damages cells</p>
