Macro-nutrients Flashcards
1
Q
Nutrition
A
Science of foods and their actions within the body substance that is absorbed into the bloodstream from the diet
2
Q
Diet
A
Selection of foods and
beverages that an individual
eats and drinks
3
Q
Classes of diet
A
- Carbohydrates
- Protien
- lipids
- Mineral salts and water
4
Q
What do macronutrients require
A
- Water
- Carbs
- Protiens
- Fats
Requires in large amounts
5
Q
Micronutients
A
- Vitamins and minerals
body require in small ammounts
6
Q
Energy yeilding nutrients
A
- Organic nutrients that are broken down to provide energy
- Carbs and protien release 4g of energy fats 9g
7
Q
Daily calorie intake
A
Energy intake from food that replaces energy
expenditure needed for all daily functions
8
Q
Low calorie intake
A
- Weight loss with nutrient deficiency
9
Q
High calorie intake
A
- Weight gain and chronic disease
10
Q
Monosaccharides
A
- Smallest sugar unit (CH2O)n
11
Q
Disaccharides
A
- Two linked monosaccaride units
12
Q
Polysaccharides
A
- Few and
thousands of monosaccharides linked together e.g. chitin, glycogen and starch
13
Q
Glucose
A
- Enter cell via active transport releases immediate energy
- Excess stored in glycogen via liver and muscle cells
- Blood glucose regulation
14
Q
Sucrose
A
- Glucose and fructose
15
Q
Lactose
A
- Galactose and glucose
16
Q
Maltose
A
- 2 glucose units
17
Q
Glycogen
A
- Multibranched polysaccharide in meats
- Storage from glucose in heptic and skeletal cells
18
Q
Starch
A
- Long branched or unbranched glucose
- Grains, ric eand wheat
- Salivary and pancreatic amylases into
disaccharides then maltose to glucose
19
Q
Dietary fibres
A
Composed of a variety of distinct monosaccharides
20
Q
Digestion of dietry fibres
A
Large intestine, where some are broken down by bacteriaTrap/get rid of bile cholesterol levels decreases
21
Q
What does low fibre cause
A
- Constipation and haemorrhoids
- Increased risk of heart diseases and some types of tumours
22
Q
Glycaemic Index
A
Food increases blood sugars and elicit insulin response
23
Q
High GI
A
Raise blood sugar high and rapidly
24
Q
Low GI
A
Rise blood sugar slowly and to a lesser extent
25
Type 2 diabetes and low GI foods
Help stabilise long-term blood glucose levels
26
High fat low GI foods
- Decrease in carb absorbtion
27
Hypoglycaemia
- Sugar deficiency causing dizziness
28
High sugar intake causes
- Obesity and wight gain and chronic diseases with dental caries
29
Non-essential amino acids
- Amino acids synthesised in the body
30
Essential amino acids
- CANNOT be synthesised by the body
▪ MUST be provided in the diet
31
Conditionally Essential Amino Acid
- Non-essential become essential for newborns
32
Complete proteins
- Containing all the essential amino acids in the required proportions
- meat, fish, soya beans, milk, and eggs
33
Incomplete protiens
- Not containg all the essential amino acids in the correct proportions.
- Mainly of vegetable origin (cereals, peas, beans, and lentils).
- A diet based on a wide variety of incomplete proteins can avoid amino acid deficiencies for vegetarian or vegan diets
34
Protein Deficiency
- Too little protein or lacks essential amino acids, Marasmus and kwashiorkor
- Weight loss slowed growth and eating disorder
35
Excess of Proteins
- Cardiovascular diseases
- Cancer (processed & red meat as carcinogens),
- Osteoporosis - calcium excretion increases, depleting the bone
- Kidney stones - Excess of Proteins
36
Protien digestion
- Pepsin and acid act on the protien forms shorter polypeptides
- Pancreas and small intestine secreate peptidase to form amino acids
37
Amino acid absorption
- Intestinal cells uptake amino acids and:
- released into the bloodstream
- used to make proteins
- converted to glucose, if needed
- broken down to provide energy via deamination producing
ammonia (NH3) that is then converted to ure
38
Lipids in nutrition
- Major fuel source during light/moderate exercise
- Major store of energy from food
- Primary component of cell membranes and nerve sheaths
* Thermal insulation for the organs
* Required for the synthesis of steroid hormones
39
Fatty acids such as triglycerides
- Glycerol backbone
- 3 fatty acid chains
40
Phospholipids
- Amphipathic molecule
- Head, phosphate and glycerol backbone with 2 fatty acid chains
41
Sterols
- Vitamins hormones and cell membranes
42
Fatty acids
Aliphatic building blocks of triglycerides, phospholipid and glycolipids
43
Degree of saturation
- Number of double bonds in the chain
44
Saturated fatty acid properties
- Solid at room temp which are more resistant and stable to oxidisation
- Animal based food causes risk factor of heart disease
45
Unsaturated fatty acids
- More unsaturated points has,
the more liquid
- The more unsaturated points, the
less stable
- Protective against chronic diseases
46
Unsaturated fatty acid properties
- More unsaturated more liquid at room temp
- Less stable to oxidation
- Plant based food and seafood
- Protective against chronic conditions
47
Example of essential fatty acids
- Linolenic acid omega 3 and 6
- Essential fatty acids must be provided by diet
48
Trans-fatty acids
- Hydrogenation of unsaturated fatty acids
- Partially hydrogenise food to extend shelf life some change configureation from cis to trans
- H opposes the double bond
49
Increase in trans fatty acids
- LDL cholesterol in blood therefore increases heart disease
50
Digestion of lipids
- Via the mouth lingual lipase via salivary glands
- Stomach gastric lipase
- Small intestine release cholecystokinin from gallbladder and bile emulsifies fat for digestion degrading triglyceride
51
Absorbtion of fatty acids
- Long chain fatty acids and monoglycerides combine with bile to form micelles diffuse and reassemble into triglycerides
- Triglycerides and phospholipids are packaged
with proteins as chylomicrons
52
Chylomicrons
- Transport vehicles
released into lymph vessels and reach the bloodstream
53
Where are triglycerides
- Stored in the adipose tissue
- In energy deficit, triglycerides are hydrolysed
to release energy
