N: SAQ's - fuckin' know the answers Flashcards
Name ONE medical condition that has been linked to an inadequate dietary intake of calcium
osteoporosis
99% of calcium stored in bone and teeth
An elderly person has been referred to you by a doctor for advice about chronic constipation. Briefly discuss the information a nutritionist would request from the person to help to formulate a dietary and lifestyle plan.
DETERMINE
List the 3 hormones/vitamins that control blood calcium levels
parathyroid hormone
calcitonin
vitamin D
Which TWO vitamins are important for DNA synthesis?
folate
B12
What is meant by the term unsaturated fat?
lack 2 or more H atoms
=> at least 1 C=C
What is meant by the term trans fat?
artificially made
changes from cis(same side) to trans(opposite) side configaration
What is the principle and desired effect of ‘carbohydrate loading’?
little evidence for benefits of carb loading for events<90 mins
events >90 mins loading= 5-12 g/kg/day
Generally speaking, how is carbohydrate loading achieved?
increasing carb intake before events of greater than 90 mins
varying from 5-12 g/kg/day
The incidences of Metabolic Syndrome and Type 2 Diabetes Mellitus are increasing dramatically in Australia and the Western world. Briefly discuss dietary and lifestyle factors that can help a person to avoid development of these disorders.
- weight management
- dietary changes: meal strategies like carb counting
- active life style
- regular monitoring
Explain in detail the role of serum lipoproteins in the development of atherosclerosis.
-> monocytes respond to injury in vessel wall, slip under vessel wall
-> engulf LDL cholesterol => foam cells
-> thin layers of foam cells develop => fatty streaks
-> fatty streaks thicken and form plaque
=> the more serum lipoproteins in artery wall the more plaque
Define the term glycemic index (GI)
food classification according to its potential for raising blood glucose
Define the term glycemic response
how quickly the blood glucose rises and elicits an insulin response
briefly explain why the body needs adequate intake of carbohydroate for the effective breakdown of fat for energy
-> energy from fat most efficiently from acetyl-CoA->TCA&ETC
-> TCA needs oxaloacetate
-> oxaloacetate made from pyruvate made from glucose(carbs)
low carb-low glycogen-low glucose-low pyruvate-low oxaloacetate
-> acetyl-CoA build up with no oxaloacetate to combine with
-> builp up causes ketone body production less efficient source of energy
digestion of FATS:
mouth: lingual lipase
stomach: muscle contractions disperse fat
SI: emulsification of fat by bile(released by gallbladder by signal from CCK)
emulsification allows pancreatic and intestinal enzyme access to hydrolyze lipids to monoglycerides, glycerol and fatty acids
digestion of PROTEINS:
stomach: does 2 things
1) denatured by HCl *essential kick to start digestion
2) pepsin cleaves protein into smaller polypeptides
SI: proteases(pancreatic & intestinal) hydrolyse polypeptides into short peptide chains(oligopeptides)
briefly explain why the body can make fatty acids from carb but cannot make carb from fatty acids:
- > fatty acids can made from carb via glycolysis
- > pyruvate last step in process, makes acetyl-CoA
- > acetyle-CoA enters TCA cycle & ETC ORRR used to make fatty acid component of fat when energy is plentiful
- > fat can be converted into acetyl-CoA then enter TCA cycle and ETC to make ATP but cannot be made into pyruvate
- > pyruvate to acetyl-CoA is an irreversible reaction
what is eclampsia? who is it likely to affect? how is it treated?
effects pregnant women usually in first pregnancy and after 20 weeks
- appears to involve immune response to placenta, vasoconstriction
- resulting in: high BP, protein in urine, fluid retention, blood flow to foetus is reduced => may result in smaller growth than usual
- treatment? immediate control of BP and seizures, induction may be necessary
list 5 water soluble vitamins
for 2, list a food source and deficiency disease
B1 thiamin - beri beri C scurvy B3 niacin B12 folate
discuss how alcohol is absorbed and metabolised in the body
- > absorbed in small intestine
- > some metabolised by dehydrogenase in stomach
- > alcohol passed through portal vein system to liver
- > LIVER! liver cells contain dehydrogenase
- > alcohol not metabolised passes around the body affecting all organs
- > (alcohol-acetaldehyde-acetate-acetylCoA-TCA or fatty acids)
outline why in excess alcohol is mostly converted into fat rather than providing its energy for ATP
- > NAD+ depleted(high alco consumption)
- > TCA cycle cannot work without NAD+ to drive it
- > acetyl-CoA produced from alcohol metabolism cannot enter TCA cycle and is converted into fatty acids for storage as fat => fatty liver (irreversible)
With reference to relevant regions of the gastro-intestinal tract (GIT), and specific digestive juices and enzymes, outline the steps involved in CARBOHYDRATE digestion, absorption and transport into the blood stream.
digestion: mouth=salivary amylase stomach=acid partially hydrolyses starch SI=pancreatic amylase hydrolyses starch absorption: active transport and facilitated diffusion, simple sugars->blood capillaries->liver->monosaccharides converted to glucose then either used for energy or stored as glycogen transport:
With reference to relevant regions of the gastro-intestinal tract (GIT), and specific digestive juices and enzymes, outline the steps involved in FAT digestion, absorption and transport into the blood stream.
digestion: stomach=muscle contractions fat into smaller droplets
SI= bile emulsifies fat, pancreatic lipase hydrolyse lipids
absorption: intestinal epithelial cells, then reform triglycerides that form chylomicrons that enter lymphatic system(to large to fit through capillaries)
chylomicrons bypass liver(not modified)-> travel directly to tissues for storage
With reference to relevant regions of the gastro-intestinal tract (GIT), and specific digestive juices and enzymes, outline the steps involved in PROTEIN digestion, absorption and transport into the blood stream.
digestion: stomach= 1. HCl unfolds 2. pepsin hydrolyses -> smaller polypeptides
SI= pancreatic protease & peptidase enzymes(polypeptides-> AAs)
absorption: specific membrane transporter molecules facilitate absorption of AA’s into intestional epithelial cells -> blood capillaries -> liver via hepatic portal vein
Oxaloacetate is a key component of which ONE of the 3 stages of metabolic energy production?
TCA cycle
first step combines with acetyl-CoA
made from pyruvate(made from glucoseCARBS)
Which important molecule does oxaloacetate combine with during metabolic energy production?
acetyl-CoA
Which molecule is oxaloacetate made from
carbohydrate
With reference to oxaloacetate briefly explain why the body needs an adequate intake of carbohydrate for efficient breakdown of fat for energy
- most efficient way to make energy from fat is through conversion of glycerol component to acetyl-CoA then enter into TCA cycle
- TCA cycle needs oxaloacetate to function properly it is involved in the first step combining with acetyl-CoA.
- oxaloacetate is made from pyruvate which is made from glucose(CARBS) therefore, low carb intake->low glycogen stores-> low glucose-> low pyruvate=> inadequate oxaloacetate levels for TCA
- this leads to acetyl-CoA build up and production of ketone bodies-a less efficient energy source
Which vitamin deficiency results in the disease rickets?
vitamin D
