phase 1 week 9 Flashcards
Describe what is recommended from the “eat well” plate
plenty of fruits and vegetables
plenty of starchy foods such as bread, rice, potatoes and pasta
some meat, fish, eggs, beans and other non-dairy sources of protein
some milk and dairy foods
just a small amount of foods or drinks that are high in fat or sugar
What is metabolism?
the sum of all chemical reactions in which energy is made available and consumed in the body
Give some uses of energy in the body
Contraction of muscle and hence for all movement
accumulation of ions and other molecules against concentration gradients
biosynthesis and hence for the building of tissues
waste disposal and hence for getting rid of the end products of bodily function
generation of heat and hence maintenance of body temperature
Describe ATP
It is often stated that ATP is the energy currency of living organisms, since hydrolysis to give ADP and Pi liberates large amounts of energy
In metabolism, ATP is continually made and broken down
How is glucose converted into Acetyl CoA?
glycolysis
How are fatty acids converted into Acetyl CoA?
beta oxidation
How are amino acids converted into Acetyl CoA?
transamination, oxidative deamination
What are the major common pathways that are the main producers of ATP?
TCA (Krebs) cycle
oxidative phosphorylation
Describe glycolysis
glucose is turned into 2 pyruvate
occurs in cytosol
ATP investment and ATP generation stages
Describe what happens to pyruvate in anaerobic conditions
pyruvate is converted into lactate, this regenerates NAD+ to keep glycolysis going
overall glucose + 2ADP +2Pi > 2lactate + 2 ATP
Describe what happens to pyruvate in aerobic conditions
pyruvate is transported to the mitochondria and converted to acetyl CoA by the action of pyruvate dehydrogenase
NADH produced
Describe the breakdown of fatty acids
released from triglyceride stores in adipose tissue via the action of lipase enzymes
transported in the blood as a complex with albumin and are taken up by cells for oxidation
They are then attached to CoA, driven by ATP and catalysed by acyl CoA synthase
Acyl groups are joined to carntitine which allows them to translocate into the mitochondria
In each reaction of the cycle the fatty acid is shortened by 2 carbon atoms, with NADH and FADH2 and acetyl CoA being produced.
Acetyl CoA enters the TCA cycle and NADH and FADH2 enter the election transport chain
What is the ATP yield from the TCA cycle and electron transport chain?
In the TCA cycle 1 GTP, 3NADH and 1FADH2 are produced
NADH yields 2.5 ATP and FADH2 yields 1.5 ATP
Total yield per acetyl CoA is 10ATP
How is glycolysis regulated?
high levels of citrate and ATP inhibit phosphofructokinase which is an important enzyme in glycolysis
Describe protein metabolism
9 amino acids are essential and must be obtained from the diet
transamination - 1 amino acid is converted to another
oxidative deamination - the amino acid of an amino acid is lost as ammonia, which can enter the urea cycle
Describe energy requirements
Basal energy expenditure (BEE) / basal metabolic rate (BMR) represent the energy required to maintain basic functions when a person is lying down, relaxed, in a normal ambient temperature
What is BMI?
Body mass index
weight/height squared
What are the ranges for BMI?
30 obese
Describe anorexia
self induced weight loss
low body weight
body image distortion
endocrine disorder
Describe the psychological presentations of anorexia
overvalued idea re weight
dysphoria
abnormal behaviours - food fads, odd eating, drink in excess or too little, secretiveness, avoidance of social eating
Describe some compensatory behaviours in anorexia
excess exercise to burn energy
use laxatives, induce vomiting
Describe some of the personality traits involved in anorexia
premorbid perfectionism introversion poor peer relationships low self esteem "perfect" child becomes angry, deceptive, manipulative, withdrawn
Describe the treatment for anorexia
inpatient / outpatient psychological intervention physical monitoring diet plan SSRIs when clear obsessional component
Describe bulimia
cravings binge eating counteractive behaviour body image symptoms physical effects to purging also malnourished can be overweight
