Nutrition And Glycolysis Flashcards
Living things require energy for…
Biosynthetic work, transport work, mechanical work, electrical work, osmotic work
ATP consists of…
Adenine ring, ribose sugar, and three phosphates
What is the definition of 1 Kcal? What is 1 Kcal in joules?
The amount of energy required to raise temperature one kilogram of water by one degree celcius.
4.2 Kilojoules
How many units do oligosaccharides consist of?
3-12
Units in: starch, sucrose, lactose, fructose, maltose, glycogen
Storage molecule in plants, glucose Glucose - fructose Glucose - galactose Monosaccharide Glucose - glucose Storage molecule in animals, glucose
What are the 9 essential amino acids?
Isoleucine, lysine, threonine, histidine, leucine, methionine, phenylalanine, tryptophan, valine
Fat soluble vitamins and their deficiencies
A - Xerophthalmia
D - Rickets
E - Neurological abnormalities
K - Defective blood clotting
Water soluble vitamins and their deficiencies (10)
B1 (Thiamin) - Beriberi B12 - Anaemia B6 - Dermatitis, Anaemia Biotin - Alopecia, scaly skin, CNS defects C - Scurvy Choline - Liver damage Folate - Neural tube defects, Anaemia Niacin - Pellagra Riboflavin - Ariboflavinosis
What is low and high fibre intake associated with?
Low - bowel cancer and constipation
High - reduce cholesterol and risk of diabetes
What do RNI, EAR and LRNI stand for?
Reference Nutritional Intake
Estimated Average Requirement
Lower Reference Nutrient Intake
What can low protein intake lead to?
Can result in insufficient blood protein synthesis leading to a decreases in plasma oncotic pressure and oedema (as seen in the disease Kwashiorkor)
Glycolysis enzymes and what they catalyse
Hexokinase (glucokinase in liver) - phosphorylates 6 carbon sugars
Phosphofructokinase-1 - conversion of fructose-6-phosphate to fructose-1,6-bisphosphate and ATP to ADP
Pyruvate kinase - phosphoenulpyruvate to pyruvate and ATP
Why does glucose get phosphorylated?
Make glucose negatively charged
Prevents passage back across plasma membrane
Increases reactivity of glucose for subsequent steps
Committing step
Step 3 in phase 1 of glycolysis, fructose-6-phosphate to fructose-1,6-bisphosphate
Allosteric and hormonal regulation of phosphofructokinase(PFK)
Allosteric - muscle, inhibited by high ATP, stimulated by high AMP
Hormonal - liver, inhibited by glucagon, stimulated by insulin
Hexokinase inhibited by…
Glucose-6-phosphate
Pyruvate kinase stimulated and inhibited by…
High insulin:glucagon ratio
Important intermediates in glycolysis
1,3-bisphosphoglycerate(haematology), dihydroxyacetone-P(production of fat)
Which reaction does lactate dehydrogenase catalyse? And where does the lactate go?
NADH + H+ + pyruvate -> NAD+ + lactate
Used in red blood cells, skeletal muscles in anaerobic respiration.
Heart or liver(gluconeogenesis)
Hyperlactaemia and Lactic Acidosis lactate concentration thresholds
Normal - <1mM
Hyperlactaemia - 2-5mM
Lactic Acidosis - above 5mM
Essential fructosuria
Fructokinase missing, fructose in urine no clinical signs
Fructose intolerance
Aldolase missing, fructose-1-P accumulates in liver, leads to liver damage, treatment - remove fructose from diet
Metabolic pathways that glucose can enter
Glycolysis, pentose phosphate, glycogen synthesis
