Mid term 2 Flashcards
How are fatty acids classified?
2% Phospholipids, 3%sterols, 95% triglycerides
How are lipids classified?
Chain length, shape/structure and saturation level
Define chain length.
small less than 6, medium 6-12, long more than 14
Define saturation level.
More hydrogen= more saturation
Define shape & structure of lipids.
Cis fatty acids- same side of Double bond . Trans fatty acids- opposite sides of double bond
How are lipids digested and absorbed?
small intestine bile emulsifies fats as the enzymes absorb them
chylomicron transport lipid particles to the lymph vessels
How are lipids transported and stored?
Transported as lipids. Large hydrophobic chains are not water soluble and need lipoproteins to transport them in the blood.
What are the four lipoproteins?
Chylomicrons, VLDL, LDL,HDL
How are lipids stored?
triglycerides, fat cells, cell membranes and lipoproteins.
What are some food sources of lipids?
Butter, Olive oil, sunflower oil, chips, nuts, cheese, avocado, fish
What is the difference between Saturated and Unsaturated fats?
Unsaturated fats: Liquid at room temperature.
Saturated fats: Solid at room temperature.
What is polyunsaturated fats and give examples.
Fat molecules with more than 1 unsaturated carbon bond.
What are some roles of lipids?
-Provide energy and aid essential physiological functions
-Protects organs and insulates the body
-Allows for absorption and transport of fat-soluble vitamins (ADEK)
-Helps with brain growth and visual centres
What do Omega 3 do?
Decreases inflammation, Blood clotting, Blood pressure (reduces risk of cardiovascular disease)
What do omega 6 do?
Increases inflammation, Blood clotting, Blood pressure (can be a positive if BP drops too much)
How much lipids do we need to consume?
20-35% of caloric intake should be from fats
0 trans fats
7-10% of total calories saturated fats
What disorders are related to lipid metabolism?
CVD
Coronary artery disease( build up of plaque in the arteries)
How many essential and nonessential amino acids are there?
9essential and 11 nonessential.
What is PKU?
Build up of amino acids in the body
How are proteins organized?
Primary sequence of amino acid, peptide bonds. Sequences of amino acids
Secondary- folded string. Hydrogen bonding of the peptide backbone causes amino acids to fold
Tertiary –3D structure, so proteins wrapped around each other. Determines the function of protein. Caused by side chain interactions.
Quaternary- Consists of more than 1 amino acid chain.
How are proteins digested and absorbed?
hydrochloric acid breaks it down in the stomach into smaller chains of amino acids.
What is the process of gene expression?
MRNA leaves nucleus and goes to the cytoplasm, then binds to ribosome and the code is translated for specific order of amino acids. Aminos acids are added to chains creating specific proteins
What is nitrogen balance?
Determines how much protein is needed
+ nitrogen balance (Nitrogen intake>Nitrogen excretion)
-nitrogen balance (nitrogen intake< nitrogen excretion)
What are food sources of proteins?
Eggs, poultry, nuts, dairy, beans, soy products, whey
What are some roles proteins play in our Body?
Cell growth, repair, and maintenance
Enzymes and hormones
Fluid and electrolyte balance
Acid−base balance
Strong immune system (antibodies)
Energy source
Nutrient transport and storage
Holds water within the blood
How much protein do we need to consume?
.8g x bodyweight
What are some nutritional implications of vegetarian diets?
Low nutrient sources.
Associated with ED
Lower digestibility
Disorders related to protein metabolism?
-pku, CF, sickle cell anemia.
- Both parents must have the dormant gene
(25% chance the kid with be born with it)
What is marasmus?
Diseased cause by low energy and protein intake.
super skinny, weakens heart muscles, stunts brain and physical dev, not reversible.
What is kwashiorkor?
caused by low protein intake. stomach distention due to fluid rendition. It’s reversible but can come back.
What is the difference between a fat and water soluble vitamin?
Water soluble: Vitamin C, B vitamins (thiamin b1, riboflavin b2, niacin b3, biotin, pantothenic acid, b6, folate,b12, absorbed into the blood, bounds to blood protein to transport, not stored, excretion=readily through kidneys, toxicity: only from fortified foods. Required 1-3days
Fat soluble: ADEK. Absorbed with lipids in lymph. Transported by being incorporated into chylomicrons. Stored in liver and adipose tissue. Not readily excreted. Toxicity is more likely. Only need them periodically weeks-months.
What are the fat soluble vitamins?
A,D,E,K
What are water soluble vitamins?
Vitamin c and b (all of them)
What can affect bioavailability?
Heat,UV,Oxidation
composition of diet
GI conditions
Sources of nutrients
prep of food
Define thiamin(b1)
Sources: pork, whole enriched grains, seeds, nuts. RDI: 1.1-1.2mg/day. Functions: coenzymes in glucose and energy metabolism. Deficiency: Beriberi (weakness, apathy, nerve tingling, paralysis) groups at risk of deficiency: alcoholics and people in poverty. Christian Eijkman in 1897 found the connection between deficiency and grains.
Define riboflavin (b2)
Sources: dairy products, whole grains, enriched greens, meat. RDI: 1.1-1.3 mg/day.function: coenzyme in energy and lipid metabolism. Deficiency: Ariboflavinosis (sores on the mouth, tongue and cracks on the corner of the mouth)
Define Niacin(b3)
Sources: beef, chicken, fish, whole grains. RDI: 14-16 mg/day. Function: coenzymes in energy metabolism and lipid synthesis breakdown. Deficiency: Pellagra, dementia, diarrhea, dermatitis. Groups at risk of deficiency: alcoholics. Toxicity: Nausea, rash, tingling extremities. Experiment by Goldberger in 1915 on Pellagra. “Poor man’s disease”. 60mg of tryptophan=1mg of niacin. 4Ds (diarrhea, dermatitis, dementia and death)
Define pyridoxine(B6)
Sources: meat, fish, poultry, legumes, whole grains. RDI: 1.3-1.7 mg a day. Major functions: Coenzymes in protein and amino acid metabolism, synthesis of hemoglobin, myelin coating and neurotransmitters. Deficiency: headache, poor growth, anemia, nausea. Groups at risk of deficiency: alcoholics. Toxicity: numbness, nerve damage
define folate(b9)
Sources: leafy greens, legumes, seeds. RDI 400microgram/day. Major functions: Coenzymes in DNA synthesis and amino acids metabolism. Deficiency: macrocytic anemia, inflamed tongue, diarrhea, poor growth. Groups at risk of deficiency: pregnant women, alcoholics.
Define B12
Sources: animal products, 2.4micrograms/day. function: coenzyme in folate and homocysteine, nerve function. Deficiency: pernicious anemia, macrocytic anemia. People at risk: vegans, elderly, people with stomach issues. Required to activate folate
What are the functions and deficiencies of vitamin c?
Function: coenzyme in collagen (connective tissue) synthesis, Antioxidant (prevents against oxidative damage by free radicals). deficiency: scurvy, poor wound healing, loose teeth, fragile
What are the functions and deficiencies of Vitamin E?
Antioxidants, protect cell membrane
Broken red blood cells
What are the functions and deficiencies of Vitamin a
Retinoids: from animals
Carotenoids: from plants
Vision health and health of the cornea
Nightblindness(Xerophthalmia)
Keratinization (hardening of eye lining)
How are blood calcium levels regulated?
Hormones that help with transport in the gut, kidenys and bones. vitamin D is in one of the hormones that plays a role
what are the functions of vitamin K and who are impacted?
Newborn, people who consume antibiotic
Blood clotting and proteins in bones
What are phytochemical?
Naturally occurring plant chemicals, not considered a nutrient.
