Nutrition, Diet And Body Weight Flashcards
What is metabolism?
The chemical processes that occur within a living organism in order to maintain life.
What is the difference between catabolic and anabolic processes?
Catabolic - the breakdown of molecules to release energy in the form of reducing power.
Anabolic - the use of energy and raw materials to make larger molecules for growth and maintenance.
What type of energy do cells use to drive every form of reaction in the body?
Chemical bond energy
What is ATP broken down into to provide energy for cell reactions?
ADP + a phosphate molecule
Can ATP be stored in the body?
No - but substances that produce ATP e.g. Fat, glycogen are. They are tied down by bonds which are then broken and released to activate ATP.
What is the definition of 1 kcal?
The amount of energy needed to raise the temperature of 1 kilogram of water by 1 degree Celsius.
Describe the basic functions for carbohydrates, protein and fat in the body.
Carbs - mostly supplies energy
Protein - energy and amino acids
Fat - energy and essential fatty acids
Describe the basic function of minerals, vitamins, water and fibre in the body.
Minerals and vitamins - essential for cell function
Water - maintains hydration
Fibre - necessary for normal GI function
What is the general formula for carbohydrates?
CH2O
What is the difference between a monosaccharide, a disaccharide, an oligosaccharide and a polysaccharide?
Mono - single sugar units (3-9 carbons)
Di - 2 units
Oligo - 3-12 units
Poly - 10-1000s units
What two molecules make up sucrose?
A glucose molecule and the fructose molecule.
What is the difference between a triose sugar, a pentose sugar and a heroes sugar?
Tri - 3 carbons
Pen - 5 carbons
Hex - 6 carbons
How many carbons are there in a glucose molecule? What type of sugar does this make it?
3 carbons
Triose sugar
What two molecules make up lactose?
Galatose and glucose
What type of molecule is starch?
A polymer of glucose (a polysaccharide)
Name three major dietary carbohydrates.
Starch Sucrose Lactose Fructose Glucose Maltose Gycogen
What can’t humans derive energy from the plant carbohydrate cellulose?
Cellulose is a polymer of glucose which can’t be digested by humans because we don’t have the enzymes to break down the beta bonds between it.
At a molecular level, what does digestion do to carbohydrates?
Converts larger carbohydrates into monosaccharides which are absorbed into the blood.
What is the molecular composition of protein?
Amino acids just by linear chains.
How many essential amino acids are there?
9
What three amino acids do pregnant women require in their diet?
Arginine, tyrosine, cysteine.
What are the 9 essential amino acids?
If Learned This Huge List May Prove Truly Valuable
Isoleucine Lysine Threonine Histidine Leucine Methionine Phenylalanine Tryptophan Valine
What are lipids made up of?
Triacyglycerols (3 fatty acids esterified to one glycerol)
What is the difference between saturated and unsaturated fat?
Sat - no double bonds, liquid at room temp.
Un - double bonds, solid at room temp.
What are trans fats?
Fats that are synthesised industrially, give food certain properties e.g. Taste better, longer shelf life.
Fat is required for the absorption of X.
X = fat soluble vitamins A, D, E, K.
What the contains the least oxygen - carbohydrate, protein or fat?
What function does this give?
Fat
More reduced for yields more energy when oxidised.
Has far more energy/calories.
What two minerals are essential for structure (bones and teeth)?
Calcium and phosphorus
Why are minerals important in our diet?
Provides electrolytes - establish ions gradients across membranes and maintain water balance.
Name some enzyme co-factors that come with a diet sufficient of minerals.
Iron Magnesium Manganese Cobalt Copper Zinc Molybdenum Iodine Selenium
What does a B1 (thiamin) deficiency cause?
Beriberi
What does a vitamin B12 deficiency cause?
Anaemia
Dermatitis and anaemia can be signs of what vitamin deficiency?
B6
What name is the name for a) a vitamin A deficiency and b) too much vitamin A?
Xerophthalmia and hypervitaminosis
What is Rickets a vitamin deficiency of?
Vitamin D
What happens if you have a vitamin K deficiency?
Defective blood clotting
What type of abnormalities could Vitamin E lead to?
Neurological abnormalities
What is scurvy a deficiency of?
Vitamin C
What is the result of a choline deficiency and what are the three key symptoms?
Pellagra - dermatitis, diarrhoea, dementia.
How does dietary fibre reduce cholesterol levels in the body?
Fibre assists with the absorption of bile in the intestines, which is then excreted in faeces. To make up for the loss of bile, the liver uses up cholesterol in the body to make more bile salts. The liver increases its production of LDL receptors, which are responsible for pulling cholesterol out of the bloodstream.
What is recommended average intake of fibre for adults?
18g/day
What is a low fibre diet and a high five diet associated with?
Low - constipation and bowel cancer
High - reduces cholesterol and risk of diabetes
What is the daily energy requirement in kJ for a 70kg male of moderate physical activity?
12,000kJ
What is the daily energy requirement in kJ for a 58kg female of moderate physical activity?
9,500 KJ
What three factors is a person’s daily energy expenditure a sum of?
Basal Metabolic Rate (BMR)
Diet-induced thermogenesis (DIT)
Physical activity level (PAL)
What is basal metabolic rate and what are some factors affecting it?
The energy needed to maintain resting activities in the body. Calories needed to ‘exist’.
Factors: Body size Gender Environmental temp Endocrine status Body temp
How many more kJ/Kg/day would you need to add on for a) a sedentary person b) moderate activity c) very active?
30 Kj/kg/day
65 Kd/kg/day
100 Kd/kg/day
In which order of the following does your body prefer to use energy up from?
Carbohydrates
Protein
Fat
1) Carbs
2) Fat
3) Proteins
What is the equation of BMI?
BMI = Weight (kg) / Height squared (m squared)
What range applies as ‘underweight’ in BMI?
Under 18.5
What classes as ‘normal weight’ in BMI?
18.5-24.9
What range classes as ‘overweight’ in BMI?
25-29.9
What range classes as ‘obese’ in BMI?
30-34.9
What classes as ‘severally obese’ in BMI?
Over 35
What is the downside of BMI and what is an alternative measurement to see if someone is a healthy weight?
Very muscular individuals may be classified as obese.
Waist/hip ratio or body fat percentage
How does a diet low in protein (malnutrition) cause abdominal oedema in children?
Not enough protein in blood vessels.
By Starling’s Law of the capillary water will always flow from the area of low to area of high solution concentration.
If there is more protein in the interstitial fluid than the blood vessels then water will flow out, saturating it.
This causes oedema.
The is the range for normal fasting plasma concentration (mmol/L)?
3.3-6.0
What is the range for normal fasting plasma concentration (mmol/L) of cholesterol?
Under 5.0
What is the range for normal fasting plasma concentration (mmol/L) of Lactic Acid?
0.6-2.4
What is the range for normal fasting plasma concentration (mmol/L) of total CO2?
22-29
What is the range for normal fasting plasma concentration (mmol/L) of urea?
2.5-7.8
What is an ‘apple shaped’ body fat distribution associated with and why?
Insulin resistance Type 2 diabetes Hypertension Stroke Premature death Hyperlipidaemia Hyperinsulinism
More fat around visceral organs - more pressure on them.
