lecture 6-8 - Carbs and Dietary Fibre

Question 1

Carbohydrates

Answer 1

Starches, Sugars, Dietary fibre and glycogen

Question 2

Monosaccharides

Answer 2

Single sugar molecules (Glucose, Fructose, Galactose)

Question 3

Monosaccharide Properties

Answer 3

Glucose (Essential energy source) Fructose (sweetest)Galactose (rarely occurs naturally as single sugar)

Question 4

Disaccharide + 3 Types

Answer 4

A double sugar consisting of 2 monosaccharides, Maltose(Glucose + Glucose), Sucrose (Fructose + Glucose), Lactose (Glucose + Galactose)

Question 5

Oligosaccharides and Polysaccharides

Answer 5

Complex carbohydrates (Oligo few glucose units) (Poly many glucose units)

Question 6

Glycogen

Answer 6

Storage form of glucose, multi branches polysaccharide (Provides glucose during <fasting= to Brain and CNS)

Question 7

Dietary Fibre

Answer 7

Parts of plants that cannot be digested, helps body eliminate waste (eg.Laxation, one of beneficial physiological effects along with reduce blood cholesterol &modulation of blood sugar) (Resistance to digestion/absorption in small intestine, usually with complete or partial bacterial fermentation in large intestine)

Question 8

Non-starch polysaccharides (resistant starch)

Answer 8

Not broken down by enzymes in small intestine, resistant due to, Intrinsic factors such as physically inaccessible, starch granules and Extrinsic factors including chewing time & transit time (Prominent part of dietary fibre)

Question 9

Free sugars (Extrinsic)

Answer 9

Extra sugar (monosaccharides/disaccharides) added to food and drink by manufacture, cook, consumer (Typically extracted, concentrated and refined from sources such as sugar cane, fruit

Question 10

Intrinsic sugar

Answer 10

Intrinsic sugar

Question 11

Reducing sugar intake, why and how

Answer 11

Energy intake and obesity, teeth and dental care, can be done by sugar tax (not used by NZ, AU), labelling, non nutritive sweeteners, modify taste

Question 12

Carbohydrate digestion

Answer 12

Amylase is an enzyme made by the pancreas (pancreatic juice)and glands in mouth and breaks down carbohydrates/starches into sugar. Carbohydrate digestion starts in the mouth with physical (chewing) and chemical digestion (amylase) and in the small intestine including intestinal enzymes (sucrase, lactase, maltase). Digestion is needed to break down polysaccharides/starches into the monosaccharides/disaccharides for absorption.

Question 13

Carbohydrate Metabolism

Answer 13

Glucose, galactose and fructose travel via the epic portal vein to liver (liver converts galactose and fructose to glucose) (Liver is blood sugar regulator). The brush border on microvilli absorb and helps breakdown glucose, lactose and fructose before going to the gut. Glucose is used for energy (brain), stored as glycogen (liver/muscle) and if energy requirements meet converted to fat

Question 14

Lactase persistence

Answer 14

Lactase enzyme able to break down lactose

Question 15

Lactose intolerance

Answer 15

Lactase enzyme unable to sufficiently break down lactose (not
HUNT TERMS TEST 5 enough lactase produced), if lactose intolerant, a sufficient amount of lactose not broken down makes it way to the large intestine causing osmotic shock and causing diarrhoea

Question 16

Lactose broken down to

Answer 16

Lactose broken down to glucose and galactose (in small and large intestine)

Question 17

Glycemic index

Answer 17

Measure of how a particular food affects food glucose level, how fast glucose broken down and released to bloodstream (High GI 70-100 → Fast, Moderate GI 56-69 → Moderate, Low GI 0-55 → Slow)

Question 18

Glycemic load

Answer 18

GI x amount of carbs / 100

Question 19

Key dietary sources of dietary fibre in NZ diet

Answer 19

Bread, Vegetables, Potato

Question 20

Bowel cancer

Answer 20

2nd highest cause of cancer death in NZ, most cases found in people over50 (not enough dietary fibre in intestine, dietary fibre converts fibre to short chain fatty acids which reduce ability of cells in intestine to become cancerous