Metab Flashcards
How many Joules in a Calorie?
4.19
What is the daily energy expenditure of a:
70kg Male?
58kg Female?
70Kg Male=12 000KJ
58Kg Female = 9 500KJ
Why is fat a necessary part of the diet? 3 reasons.
Absorb fat soluble vitamins D,A,K,E
Structural component of cell membranes
Precursors of Regulatory molecules eg Eicosanoids
Give an example of an essential fatty acid.
Linoleic
What is the necessary daily intake of protein?
35g
What is the Daily water loss?
2.5 litres
What is the minimum daily glucose intake?
What proportion is used on glucose requiring tissue, eg RBC, and the CNS
180g
40g for glucose requiring tissue eg RBC
140g for CNS
What type of diet causes Marasmus?
Protein and Carbohydrate deficiency
What are the symptoms of Marasmus? List three.
Other possible symptoms?
Emaciated, muscle wasting, thin and dry hair
Possible diarrhoea and anaemia
NO ODEMA
What type of diet causes Kwashriorkor?
Some Carbohydrates but very low protein intake.
What are the symptoms of Kwashiorkor? List 4
Other possible symptoms?
Apathetic, Lethargic, Anorexic, Heapatomegaly or ascites (accumulation of fluid in peritoneal cavity ie Odema)
Possible anaemia
Does Marasmus or Kwashiorkor result in Odema and why?
Kwashiorkor.
No muscle wasting hence (as it is not required to get energy) resulting in a low serum albumin concentration, causing water to move into the tissue fluid.
The equation for BMI
Weight (kg) / Height x Height (m)
What BMI range indicates some one is underweight?
Lower then 18.5
What BMI range indicates that someone is obese?
30-35
What BMI range indicates someone is severely obese?
Above 35
What type of hormone control is local release via ducts/endocrine?
Para crime control
What type of hormone control effects the cell that releases the hormone?
Autocrine
What are the two branches of the peripheral nervousness system. What is their input/output?
Afferent branch, sensory input
Efferent branch, motor output
What is the function of cortisol?
Indicate low blood glucose levels
Addison’s disease
Hypo activity of adrenal cortex hence low blood cortisol concentration.
Cushing’s Syndrome
Hyperactivity of adrenal cortex resulting in high cortisol blood concentration.
Define cell metabolism.
Highly integrated network of chemical reactions that occur within cells.
What is an exertion id reaction?
One that releases energy.
Gibbs Free Energy change is negative.
What enzyme catalyses the formation of creatine phosphate from creatine?
Creatine kinase
What high ratio activates catabolic reactions?
ADP/AMP
What high ratio stimulates anabolic reactions?
ATP/ADP
What are the two types of monosaccharide?
Aldosterone and Ketose
What is the name of the bond between monosaccharides?
Glycosidic
What is sucrose made of?
Glucose and Fructose
What is lactose made of?
Galactose and glucose
What is maltose made of?
Glucose-Glucose
Why can we not digest cellulose?
It contains beta 1-4 glycosidic bonds. We do not have enzymes to break this bond.
What type of enzyme catalyses the break down of polysaccharides? What are they made of?
Glycosidase enzymes, made from large glycoprotein complexes.
What are the 4 main enzymes involved in the catabolism of disaccharides?
Lactase, Glycoamylase, Sucrase, Isomaltase.
What is step 1 of glycolysis? Which enzyme catalyses it?
Glucose -> Glucose 6 Phosphate
Hexokinase
Glucokinase in the liver
What is step 3 of glycolysis? Which enzyme catalyses it?
Fructose 6 Phosphate -> Fructose 1,6 bisphosphate
Phosphofructo kinase 1
What is step 10 of glycolysis? what enzyme catalyses it?
Phosphoenolpyruvate -> Pyruvate
Pyruvate kinase
What enzyme catalyses the production of lactate from pyruvate?
Lactase dehydrogenase
What is the normal plasma concentration range of lactate?
> 1mM
What occurs when the plasma lactate concentration rises above 5mM?
It exceeds the renal threshold, buffers cannot resist the change in pH hence lactic acidosis occurs.
What is the process of converting galactose to glucose-6-phosphate? What enzymes are involved?
Galactose -> Galactose 1 Phosphate -> Glucose 1 Phosphate
-> Glucose 6 Phosphate
Galactokinase
Galactose 1 phosphate uridyl transferase.
Which enzyme is most likely to have a reduced activity in Galactosaemoa?
Galactose 1 phosphate uridyl transferase
What alternative reaction will occur in Galactosaemia, and hence what is there a build up of?
What does this reaction deplete?
Galactose -> galactitol
NADPH->NADP
What are the symptoms of Galactosaemia?
Cataracts, raised intra-ocular pressure that can lead to blindness,
Damage to liver, kidney and brain as phosphate locked in galactose 1 phosphate.
Heinz bodies forming , this could lead to anaemia and jaundice.
Why does a lack of NADPH result in cataracts and Heinz bodies forming
The NADPH maintains a reducing environment to prevent cysteine in proteins from storming disulfide bridges between themselves. If these bridges form the strucure of the protein will be altered.
Hence in the eye it no longer has a crystalline structure.
