Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HNSC 1210 > Carbohydrates > Flashcards

Carbohydrates Flashcards

1
Q

Carbohydrates

A

Carbon, Hydrogen, Oxygen (CHO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Energy Cycles

A
  • Through photosynthesis, plants combine carbon dioxide, water and the sun’s energy to form glucose
  • When humans metabolize glucose, energy and carbon dioxide are released
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Types of carbohydrates

A
  1. Simple CHO (sugars)
  2. Complex CHO or polysaccharides (starch and fibre)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Simple Carbohydrates

A
  1. Monosaccharides
    • Glucose
    • Galactose
    • Fructose
  2. Disaccharides
    • Sucrose (glucose + fructose)
    • Maltose (Glucose + Glucose)
    • Lactose (Glucose + Galactose)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Glucose (Monosaccharides)

A

Brain is completely dependent on glucose as its energy source

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Galactose (Monosaccharides)

A

Differs from glucose only in that hydroxyl group faces in a different direction on the number four carbon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Fructose (Monosaccharides)

A
  • Same chemical formula as glucose but different structure
    • Natural sources: fruits, honey, sugarcane
    • Also found in soft drinks, cereals, and products sweetened with high fructose corn syrup
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Disaccharides

A

Pairs of two monosaccharides linked together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Sucrose (glucose + fructose) (Disaccharides)

A

Table sugar, also found in many F&V, especially sugar beets and sugarcane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Maltose (Glucose + Glucose)
(Disaccharides)

A
  • Common breakdown product of plant starches, rarely found in foods
  • Associated with sweet taste in mouth when chewing bread
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Lactose (Glucose + Galactose)
(Disaccharides)

A

Milk sugar, found in dairy products like milk, yogurt, cheese

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Polysaccharides

A

Long chains of monosaccharides that may be branched or not branched

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Plant forms: Starch and fibre (Polysaccharides)

A

Human digestive enzymes can break the bonds between glucose units in starch but not in fibre (e.g., cellulose)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Animal form: glycogen (more branched)
(Polysaccharides)

A
  • Human digestive enzymes can break the bonds
  • Found in liver and muscle (meat)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Recommendations

A
  • DRI
    • 45-65% of energy from carbohydrates, emphasis on complex and whole grain
    • Minimum 130 grams per day
    • <25% of energy from added sugars
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Food Sources

A
  • Pasta
  • Rice
  • Beans
  • Cereals
  • Breads
  • Milk/milk products
  • Fruits
  • Starchy Vegetables (Potatoes, Peas, Corn, Squash)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Dietary Fibre

A
  • Suggested intake:
    • WHO: >25 g per day
    • DRI:
      • <50 yrs: males 38g/d; females 25 g/d
      • > 50 yrs: males 30 g/d; females 21 g/d
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Water Soluble Fibre (Types & Sources)

A
  • Types:
    • gums, mucilages, pectins, psyllium, some hemicellulose
  • Sources:
    • Oats, oat bran, barley, rye, seeds, fruits, vegetables,legumes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Water Soluble Fibre (Benefits)

A
  • Lower blood cholesterol
  • Slow glucose absorption
  • Slow transit of food through upper digestive tract
  • Hold moisture in stools, softening them
  • Yield small, fat-like molecules after fermentation that the colon can use for energy
  • Lower risk of heart disease and diabetes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Insoluble Fibre (Types & Sources)

A
  • Types:
    • Cellulose, lignin, and some hemicellulose
  • Sources:
    • Brown rice, wheat bran, whole grains, seeds, fruits, vegetables, legumes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Water Insoluble Fibre (Benefits)

A
  • Increase fecal weight
  • Increase colonic transit
  • Alleviate constipation
  • Reduce risk for diverticular disease, hemorrhoids and appendicitis
  • Provide bulk and feeling of fullness
  • Weight management
22
Q

Consumer Corner

A
  • If a bread contains a refined flour, the husk, germ and bran have been removed lower in nutrients and fibre
  • If a bread contains an enriched flour, some or all of the nutrients lost when the flour was processed have been added back
23
Q

How Carbohydrates in Food Become Glucose in the Body

A
  • Mouth
  • Stomach
  • Small Intestine
  • Fibre travels unchanged to the colon
  • Absorption of glucose, fructose and galactose into bloodstream
  • Liver
  • All digestible CHO becomes glucose in the body and is used for:
    • Energy (Directly, or from glycogen stores)
    • Glycoproteins (CHO attached to proteins) e.g. mucus, cell membranes
24
Q

Mouth (Glucose in the Body)

A

Minor digestion by salivary amylase (5%)

25
Q

Stomach (Glucose in the Body)

A

Mechanical digestion, turns bolus to chyme

26
Q

Small Intestine (Glucose in the Body)

A

Digestion by pancreatic amylase (starch disaccharides) and enzymes on intestinal wall (disaccharides monosaccharides)

27
Q

Liver (Glucose in the Body)

A

Liver converts galactose and fructose to glucose

28
Q

Postprandial CHO Metabolism

A
  • Blood glucose rises after eating CHO
  • Amount of increase reflects:
    • Amount of CHO consumed
    • Rate of digestion and rate of entry into bloodstream
    • Rate of uptake by the cells
29
Q

Blood Glucose (1)

A
  • Under homeostasis
    • Is tightly regulated
  • Normal fasting blood glucose level is 4 - 6 mmol/L
  • Hypoglycemia
    • Low blood glucose
  • Hyperglycemia
    • High blood glucose
30
Q

Blood Glucose (2)

A
  • When blood glucose is low, the pancreas releases glucagon (hormone)
    • Breakdown of liver glycogen → glucose → blood → tissues for energy
    • Glucose is produced from protein (gluconeogenesis)
    • If this occurs on a long-term basis (e.g. disease states) then result is muscle wasting
31
Q

Ketosis

A
  • Need minimum 130 g CHO/day to prevent ketosis and spare protein (muscle)
    • Usually consume 200-400 g CHO/d
  • Liver glycogen lasts 4-6 hrs depending on CHO intake, exercise , etc.
  • If liver glycogen is depleted, then ketosis occurs
32
Q

Diabetes (1)

A
  • Type 1 (early or mid-life, <10% cases)
    • Hyperglycemia due to little or no insulin produced by the pancreas
    • Auto-immune response
    • Untreated: glucose wasting (urine) and weight loss
    • Treatment: insulin is injected to match food intake and physical activity
33
Q

Diabetes (2)

A
  • Type 2 (T2D)
    • Formerly adult, now children/teens = >90% cases
    • Hyperglycemia due to insulin resistance (associated with overweight and obesity)
    • Pancreas produces lots of insulin, but cells respond poorly
    • Chronic hyperglycemia increases risk of cardiovascular disease, kidney disease, cataracts/blindness, amputations, etc.
34
Q

Risk Factors for T2D

A
  • Family history
  • Sedentary lifestyle
  • Overweight / obese
  • Moderate weight gain in adulthood
  • History of gestational diabetes
  • Genes: Aboriginal, African American, Hispanic, Asian, Pacific Islander descent
35
Q
A
36
Q

Warning Signs of T2D (1)

A
  • Excessive urination and thirst
  • Glucosuria (glucose in urine)
  • Weight loss, nausea, weakness, irritability
  • Cravings for food, especially sweets
  • Drowsiness, tire easily
  • Vision disturbances
37
Q

Warning Signs of T2D (2)

A
  • Frequent infections (e.g. skin, gums, urinary tract, yeast)
  • Slow healing of cuts and bruises
  • Pain in legs, feet, or fingers
    • Usually with tingling due to nerve damage
  • Abnormally high glucose tolerance test results
38
Q

Management of T2D

A
  • Diet and physical activity
    • 10% weight loss is beneficial
  • Oral agents
  • Sometimes insulin injections
39
Q

Glycemic Effect of Food (1)

A
  • Extent to which foods elevate blood glucose compared to a glucose solution or white bread
    • Low number considered best: legumes, peas
    • High number: white bread, juice
40
Q

Glycemic Effect of Food (2)

A
  • Factors to consider:
    • Type of food:
      • Apple < apple juice
    • Cooking method:
      • Baked potato < mashed
    • Eaten alone or part of a mixed meal
41
Q

Glycemic Effect of Food (3)

A
  • Limitation
    • Does not consider amount of carbohydrate, only type
    • Combining different high and low GI foods changes the GI for the overall meal (glycemic load)
    • Some nutrient dense foods have higher GIs than less nutritious foods
      • EX: oatmeal has higher GI than chocolate because chocolate has higher fat content
42
Q

Carbohydrate Counting

A
  • Simple, flexible meal planning tool
  • Want consistent CHO intake at meals
  • Grains, fruits, milk, sweets, all CHO choices
    • 1 grains & Starch choice = 15 g CHO
    • 1 Fruits choice = 15 g CHO
    • 1 Milk & Alternatives choice = 15 g CHO
  • Meat & Alternatives and Fat choices do not contain CHO
43
Q

Lactose Intolerance (1)

A
  • In sufficient lactose enzyme activity to digest lactose → glucose + galactose
    • Develops in adults of non-Northern European background
  • Signs: nausea, pain, diarrhea, and gas
    • More osmotic particles draws water
    • Bacterial fermentation in intestine
44
Q

Lactose Intolerance (2)

A
  • Management:
    • Consume milk in small amounts (1/2 - 1 cup) with meals
    • Yogurt, aged cheeses
    • Products treated with lactase (e.g. Lactaid milk, ice cream)
    • Add enzyme drops to milk-based foods
    • Lactaid pills
45
Q

Milk Allergy

A
  • Need non-dairy sources of calcium:
    • Calcium-fortified soy milk and orange juice
    • Canned sardines or salmon with bones
    • Vegetables (e.g. broccoli, bok choy)
    • Consider a calcium supplement
46
Q

Controversy 4: Sugars and Health (1 Do sugars play a role in)

A
  • Obensity?
  • Aggravating diabetes?
  • Increasing risk for heart disease?
  • Behavioral problems?
  • Dental problems
47
Q

Controversy 4: Sugars and Health (2 Use sugar in moderation)

A
  • WHO: <10% Calories from added sugars [DRI: <25%]
  • IOM: no more than 25% of total calories from added sugars
48
Q

Controversy 4: Sugars and Health (3 Added vs natural Sugars)

A
  • Added
    • Sugars and syrups added to foods during processing or preparation
      • EX: brown sugar, corn syrup, dextrose, fructose, fruit juice concentrates, maple syrup, sucrose, and raw sugar that are added to foods
  • Natural
    • Naturally occurring in foods and have not been added
      • Includes the above natural sources
49
Q

Controversy 4: Sugars and Health (4 Sugar Alcohols)

A
  • members of chemical alcohol family (structure)
  • Sorbitol, mannitol, xylitol, isomalt, maltitol, lactitol
  • Not readily used by mouth bacteria
  • All have 3-5 Calories/g but poorly absorbed
50
Q

Controversy 4: Sugars and Health (5 Artificial Sweeteners (1))

A
  • Aspartame (200 x sweeter than sucrose),
    acesulfame-K (200 x), sucralose (600 x)
    [cyclamate and saccharin have restricted
    uses in Canada]
  • Calorie-free because so little is used
  • Aspartame = phenylalanine + aspartic acid, 4 cal/g from the amino acids but calorie-free; product warning for
    people with PKU (phenylketonuria)
51
Q

Controversy 4: Sugars and Health (6 Artificial Sweeteners (2))

A
  • Acceptable daily intake (ADI) is the estimated amount of sweetener that can be consumed daily over a person’s lifetime
    without any adverse effects
  • ADI = 40 mg/kg body weight for aspartame in Canada
  • 150 lb (68 kg) person: ~72 packets of Equal or ~13 diet soft drinks

HNSC 1210 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions