Module 02 Flashcards
What is the ratio of oxygen to hydrogens in carbohydrates?
1 oxygen for every 2 hydrogens
What are the three monosaccharides?
Glucose, fructose, and galactose
What kind of reaction breaks monosaccharides apart?
Hydrolysis
What kind of reaction puts monosaccharides togehter?
Condensation
What are oligosaccharides?
3-10 monosaccharides stuck together
What are polysachharides?
Many (100’s-1000’s) monosaccharides linked together
What are complex carbohydrates?
Starch
What is the difference between starch and glycogen?
Starch is glucose storage in plants and glycogen is glucose storage in animals
What are examples of fibre?
Cellulose, hemicellulose, and lignin
How much fibre should we consume?
14g per every 1000 calories
What digests carbohydrates in the mouth?
Salivary amylase
What breaks down starch in the small intestine and what does it turn into?
Pancreatic amylase converts starch into maltose
What breaks maltose down in the small intestine and what is the product?
Maltase releases two molecules of glucose
What breaks sucrose down in the small intestine and what is the product?
Sucrase releases a molecule of glucose and a molecule of fructose
What breaks lactose down in the small intestine and what is the product?
Lactase releases a molecule of glucose and a molecule of galactose
What happens to glucose in the liver?
It fuels the liver, it is stored as glycogen, it is used to make amino acids, it is converted to fat, or it is released into the blood stream
Which cells require glucose to function?
CNS, brain, and red blood cells
When is insulin released?
When food is consumed
What does insulin do?
Facilitates the uptake of glucose, stimulates glycogen and fatty acid synthesis, and returns blood glucose levels to normal
What is released in response to low glucose?
Glucagon
What does glucagon do?
Causes glycogen to break down to restore glucose levels to normal
What are some things that increase the risk of diabetes?
Age, being sedentary, family history, high blood pressure, and being overweight
What is glucose intolerance?
The inability for cells to recognize the presence of glucose
What is type one diabetes mellitus?
Failure of the pancreas to produce and/or release functional insulin
What is type two diabetes mellitus?
Cells are resistant to the insulin produced by the pancreas
What is glucose tolerance?
The measure of a person’s ability to remove excess glucose following a meal
What are some signs of diabetes in a glucose tolerance test?
High fasted glucose levels, high peak, highest point is delayed, blood glucose stays high for longer than normal
What is the renal threshold for glucose?
10mmol/L
What is the major source of fructose in our diets?
High fructose corn syrup, which is found in pop, tomato sauces, candy, cereal, and condiments
Which sugar is more cariogenic: Glucose or fructose?
Glucose
How is fructose used differently by the liver?
It stimulates liver fat synthesis
What is sucrose?
A disaccharide that is isolated and purified from sugar beet or sugar cane
What is sucrose proven to be linked to?
Cavities
What are the five factors which make up metabolic syndrome?
Abdominal obesity, high fasting glucose, elevated blood triglycerides, low levels of HDL in the blood, and elevated blood pressure
How much of our diet should be made up by added sugars?
Less than 10%
What is lactose?
The sugar found in milk. It is a disaccharide made up of glucose and galactose
What causes lactose intollerance?
Lactase deficiency
What happens due to lactose intollerance?
There is no breakdown of lactose and it moves with a lot of water to the colon where it is fermented by bacteria. This causes bloating, cramps, and diarrhea
What is a milk allergy?
An exaggerated immune response to the protein in milk
What is resistance starch?
It moves through the intestines like soluble fibre, as it can not be broken down. It is found in okra, legumes, and reheated potatoes.
How does soluble fibre work in the body?
It forms a gel in the gut which slows the rate of food moving through the body
Where does soluble fibre come from?
Pectin, gum, carrageenan, and agar
Food sources are fruit pulp, oatmeal, psyllium, and the insides of legumes
How does insoluble fibre work in the body?
It increases the speed at which food moves through your body
Where does insoluble fibre come from?
Psyllium, cellulose, hemicellulose, lignins, wheat bran
Food sources include plants, vegetables and fruit skins, and legume skins
What is soluble fibre digested into?
Short chain fatty acids (2:0, 3:0, and 4:0)
What benefit does insoluble fibre have?
It produces a larger fecal bulk which prevents constipation and allows harmful substances to be removed, increases the removal of toxins, and alters bile acid metabolism to prevent the formation of secondary bile acids
What is the best source of insoluble fibre?
Wheat bran
How is soluble fibre important for health?
It makes short chain fatty acids which help prevent cancer, lowers the pH, crowds out bad bacteria, and reduces ammonia levels
How does soluble fibre impact the risk of coronary heart disease?
It binds to cholesterol and bile acids which causes them to be removed, and produces 3:0 which shuts down liver synthesis of cholesterol
How does fibre impact weight?
It increases the feeling of fullness, delays gastric emptying, and takes longer to eat
How much fibre is recommended to eat per day?
14g per 1000kcal we consume
How much of protein is nitrogen by weight?
16%
What are the four groups attached to the amino acid central carbon?
A hydrogen, an amino group, and acid group, and a variable side chain (R) group
What is the R group of glycine?
H
What is the R group of methionine?
CH2CH2S
What is the R group of phenylalanine?
An aromatic benzene ring
What is phenylketonuria and why is it a concern?
Inability to process phenylalanine
Can case CNS damage and mental disabilities
What are the essential amino acids?
Histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine
What kind of reaction joins two amino acids and what is the bond called?
A condensation reaction forms the peptide bond
What is the primary structure of proteins?
A linear arrangement of amino acids
What is the secondary structure of proteins?
The configuration of the amino acids based on their side chain structures
What is the tertiary structure?
The 3D shape that the protein folds into
How do the two proteins which make up insulin interact with each other?
Disulfide bonds
What is denaturation?
Destroying the 3D shape of a protein using heat or chemicals
What binds to the heme iron in hemoglobin?
Oxygen and CO2
What causes sickle cell anemia?
A single amino acid change
What does protein do in the body?
Regulates body processes, growth and repair of tissues, immune defense, transportation, and energy
Where does protein digestion begin?
The stomach
What in the stomach helps with protein digestion?
HCl denatures the proteins and pepsin breaks some peptide bonds
Which enzymes for protein digestion come from the small intestine?
Active intestinal enterokinase and intestinal pre-peptidases
Which enzymes for protein digestion are secreted from the pancreas?
Trypsinogen and chymotrypsinogen
Which enzyme activates trypsinogen into trypsin?
Intestinal enterokinase
What enzymes does trypsin activate?
Pre-peptidases (into peptidases) and chymotryspinogen (into chymotrypsin)
What happens to amino acids once they reach the liver?
They can be used to synthesize proteins, used for energy, converted into glucose or fat, or sent into the bloodstream
What are exogenous and endogenous amino acids?
Exogenous amino acids come from food sources
Endogenous amino acids come from tissue breakdown
What is the first step of amino acid breakdown?
Deamination (removal of the amino group)
What factors influence protein quality?
How digestible a protein is, the types of amino acids present, and the proportion of amino acids
What is the ideal protein source?
A chicken egg or human milk
Which proteins are higher quality?
Proteins of animal origin
Which two plant based proteins, when eaten in combination, meet all of your needs?
Legumes and grain products
What is a zero nitrogen balance?
The amount of nitrogen we consume is equal to the amount we excrete
What is a positive nitrogen balance?
We are consuming more nitrogen than we are losing
What is a negative nitrogen balance?
We excrete more nitrogen than we consume
What is the range for protein intake?
10-35%
What is the RDA value for adult protein intake?
0.8g/kg/day
What is a major concern with amino acid supplements?
Overwhelming transporters for multiple amino acids with a huge amount of one amino acid can cause deficiencies in the other types
What are some concerns with excess protein intake?
Increase in total daily kcal, increase in saturated fats (depending on protein choice), bone health, overwork or damage to the kidneys, and cancer
