Exam 2- Midterm Flashcards
The preferred energy source for nerve cells?
Carbohydrates
Amylose
Straight chain of glucose molecules.
Resistant starch (fiber)
Glucose molecules linked by beta bonds are largely indigestible.
Glycogen
The storage form of glucose for animals (humans)
Functional Fibers
Are extracted from plants or manufactured in a laboratory that have known health benefits
Soluble fibers
Found in beans, citrus foods, berries, and oats.
Insoluble Fiber
Examples: lignins, cellulose, and hemicelluloses.
Amylase
Digestion breaks down most carbohydrates into monosaccharides.
Stomach acids inactivate ________________.
Salivary amylase.
Glucose and galactose are absorbed via ____________.
Active Transport.
Fermentation produces ______ and _____________.
Gases, short-chain fatty acids.
Glucagon
Stimulates the liver to convert glycogen to glucose.
Foods with a High Glycemic Index…..
Cause a sudden surge in blood glucose, triggering a large increase in insulin, which may be followed by a dramatic fall in blood glucose.
Foods with a low glycemic index…
Cause low to moderate fluctuations in blood glucose,
Higher fiber foods…
Help to regulate blood glucose.
Ketosis occurs when….
Carbohydrate intake is too low to supply glucose to the brain.
Recommended Dietary Allowance (RDA) of carbohydrates
130 grams/day
Whole grains have a _________ glycemic index.
Lower.
What mineral do people with lactose intolerance need to find an alternative for?
Calcium.
Three types of lipids are found in foods and in body cells and tissues:
-Triglycerides
-Phospholipids
-Sterols
Triglycerides consist of:
-One glycerol molecule (backbone)
-Three fatty acid molecules (tails)
Polyunsaturated Fatty Acids
Have more than one double bond.
Saturated Fatty Acids
Solid at room temperature
-examples include: animal fats, butter, and lard
Essential Fatty Acids
Cannot be made by the body and must be obtained from food. Food sources are walnuts, chia seeds, flax seeds, and fish
-Precursors to eicosanoids which regulate cell function
Omega-3 Fatty Acids
-Eicosapentaenoic acid (EPA)
Docosahexanoic acid
-reduce inflammation and blood triglycerides.
Phospholipids
Only lipid soluble in water.
Sterols
Used to make adrenal and sex hormones, vitamin D, bile.
Micelles
Capture lipid digestion products and transport them to the enterocyte for absorption.
Blood lipids include
-Chylomicrons-present only after a meal
-Very-low-densitiy lipoproteins (VLDL)
-Low-density lipoproteins (LDL)
-High-density lipoproteins (HDL)
Plaque formation
Thick deposits of foam cells, platelets, calcium, and protein block blood flow in the artery.
Proteins
Dictated by genetic material (DNA)
Transamination 1
Transfer amine group from an essential amino acid to a different acid group and side chain (R Group).
Transamination 2
-Produce nonessential amino acids.
-Occurs mostly in the liver.
Peptide bonds
Join amino acids together forming proteins (dipeptides, tripeptides, oligopeptide, and polypeptides).
Protein turnover
Existing proteins are degraded (broken down) to provide the building blocks for new proteins.
Protein Denaturation
Proteins uncoil and lose their shape when exposed to heat, acid, base, heavy metal, and alcohol.
Pepsin
Enzyme begins breakdown of proteins into short polypeptides and amino acids
Pancreatic enzymes (proteases) complete protein digestion.
-Trypsin
-Chymotrypsin
-Carboxypeptidase
Chemical Score
Comparison of the amount of the limiting amino acid in a food to the amount in a reference food.
Marasmus
Grossly inadequate energy, protein, and nutrient intake.
