Biomolecules Flashcards
(29 cards)
Name the dietary carbohydrates and relevant info
1) Starch
- Food source for plants
- Polysaccharide of GLUCOSE
2) Sucrose
- Found in fruits and vegetables
- Disaccharide of glucose and fructose (think Fruit-close)
3) Dietary fiber
- Comes from plants (Grains, etc.)
4) Lactose
- Sugar from milk, therefore animal origin
- Disaccharide of glucose and galactose (think (ga - lactose)
Describe Lactose Intolerance
1) Genetic deficiency of lactase enzyme, which breaks down milk
- Age-dependent decrease in enzyme (i.e. gets worse with age)
2) Results in gas, bloating and belly pain within 2 hours of consuming lactose.
What does catabolic vs anabolic mean
Catabolic - breakdown
Anabolic - buildup
Describe the good, the bad and the ugly of blood glucose levels and the impact
Hypoglycemia ——- <60 mg/dL (hunger, sweating, trembling)
——- <40mg/dL (coma, brain damage, death)
Normal —————- 70-100mg/dL (fasting), 100-140mg/dL (fed)
Diabetes mellitus — > 126mg/dL (fasted), >199mg/dL (fed)
Explain Glycolysis (as well as a certain pathology marker…)
1) The metabolism of glucose (how most cells generate energy)
2) Energy formed = 2 net ATP
3) 6 Cs of glucose are broken down to 2x 3Cs of pyruvate
Aerobic conditions = suppressed glycolysis (EXCEPT CANCER)
-Which is why cancer is a good marker (done with PET scans)
What is the formula for glucose?
C6 H12 O6
monosaccharides
Simplest carbohydrate form
Provide short-term energy
1) Glucose
2) Fructose
3) Galactose
4) Ribose
Mnemonic — Good Roads Find God
Disaccharides (and alpha, beta linkages)
Comprised of two monosaccharides
1) Maltose (alpha 1->4 bond)
2) Lactose (beta 1-4 bond
3) Sucrose (alpha 1, beta 2 bond)
Mnemonic - Many Liquid Sugars
Oligosaccharides
- Made of 3 to 10 monosaccharides
- Covalently attaches to membrane proteins and lipids
1) Glycolipids
2) Glycoproteins
Polysaccharides (types and purpose)
- More than 10 monosaccharides
- Important for:
- Carbohydrate storage
- Structural/mechanical support (especially cellulose)
1) Glycogen ———- Chains are a(1-4), Branches are a(1-6)
2) Starch—————Chains a(1-4), branches a(1-6) (water soluble!)
3) Cellulose————Chains b(1-4)
Name the Modified Monosaccharides
1) Deoxyaldose - in DNA (that’s why deoxyribonu…)
2) Acylated amino sugars - part of Glycolipids and proteins, thus important for cell signaling
3) Acidic sugars - Located in 1) Cell membrane and 2) the extracellular matrix
4) Food additives —— Sugar Alcohols (Mannitol, sorbitol, xylitol,etc.) -important in diabetes because SORBITOL could lead to peripheral neuropathy
- Galacitol could cause cataracts
Describe a Glycosidic Bond and the alpha and beta differences
A covalent bond, formed during a condensation run, between a carbohydrate and another group, usually a carbohydrate
Alpha Linkage - glycosidic bond is below the plane of the sugar rings
Beta Linkage - glycosidic bond is above plane as the sugar rings
TIP! - aBove the sugar rings, its Beta (not the uppercase B)
Relevance of sugar alcohols (sweetness) in diabetes??
1) Glucose in the body can be converted into Sorbitol
2) Sorbitol draws water into wherever it is, leading to the destruction of the:
Lens -> cataracts
Pericytes ->retinopathy
Schwann cells -> peripheral neuropathy
Facts about Sugar alcohols?
1) Fewer calories per gram than sugar
2) Not as readily absorbed
3) No tooth decay
Name two types of starch and their alpha, beta linkages
1) Amylose (found this form 25% of the time) — alpha(1-4)
2) Amylopectin (found this form 75% of time —- a(1-4) and a(1-6)
Four types of Dietary Lipids
1) Fatty Acids—————-long, uncbranced hydrocarbon chains
2) Triacylglycerol
3) Cholesterol esters
4) Phospholipids
Structure of ester, carboxylic acid and glycerol
??
Cholesterol esters
Fatty acid esterified to a cholesterol
Fatty acid + cholesterol
Triacylglycerol
3 Fatty Acids + glycerol backbone
Membrane Lipids
1) Glycerophospholipid—-fatty acid + glycerol + phosphate
2) Sphingophospholipid—fatty acid + amino alcohol or sugar alcohol
3) Glycolipid——————sugar + fatty acid
Lipid-soluble Vitamins (And IPP unit number)
Vitamin A—leafy vegetables, carrots (def.= night blindness) (4)
Vitamin D—sunlight, fortified milk (def.= no bone mineralization) (6)
Vitamin E—veg. Oils, leafy vegetables (def.= muscular dystrophy)(4)
Vitamin K—leafy vegetables (def. poor blood coagulation)(4)
All are 4 IPP units except Vitamin D
Omega 3 & Omega 6 fatty acids
The “3” and the “6” indicate the location of the terminal double-bond. Count # of carbons from end to double bond.
Ex. Linolenic acid is w-3
Ex. Linoleic & Arachidonic acids are w-6
Isoprenoids (structural features)
1) Lipids made from ACETYL CoA from isopentenyl pyrophosphate (IPP)
2) Organic compounds from 2 or more hydrocarbon units, consisting of 5-carbon atoms
3) IPP condensation = creation of isoprenoid (steroids, lipid soluble vitamins, etc.)
Most Common & important——-> Cholesterol
Cholesterol (& associated pathology)
1) Most common steroid
2) Important as:
-Precursor to other steroids, bile and Vitamin D
-In membranes
Pathology: Gallstones
1) Salt in the gallbladder keep cholesterol in solution (aqueous state)
2) Too much cholesterol/too little salt results in cholesterol precipitating into GALLSTONES
3) Ongoing issues with metabolism can lead to 1) malabsorption (decreased ability to absorb food) and 2) fat-soluble vitamin deficiencies)
4) This is because bile is needed to emulsify fats - remedy is Chenodeoxycholic, which can dissolve gallstones.
