when a fatty acid is described as being saturated, it means that it

contains only single bonds between its carbon atoms

fatty acids vary in their degree of saturation or unsaturation due to number of

double bonds

position of double bond closest to the methyl (CH3) end of fatty acid is described by an _____ number

omega

what behaves more like saturated fats, increasing blood cholesterol, and heart disease risk

trans fatty acids

what member of lipid family are soluble in both water and fat

phospholipid

the function of bile in fat digestion is to

emulsify fats into smaller particles

what happens to the bile that is reabsorbed by the small intestine

most of the bile is reabsorbed from the small intestine and recycled

what blood lipid is linked most directly to heart disease

LDL

when food is consumed, which organs is excess energy stored in

adipose cells

what is primary role of triglycerides

provide cells with energy

a desirable blood lipid profile would include a(n)

LDL cholesterol of <100 mg/dL

what type of dietary fat can increase LDL concentrations

saturated fatty acids? trans fatty acids

is fat source is counted toward an individuals discretionary kcals, what does it mean?

fat source is high in saturated fat, and its intake should be limited

are lipids soluble in water

no

example of saturated fat & descriptions of its structure

butter, no double bonds on carbon chain, straight

example of monounsaturated fat & descriptions of its structure

olive oil, bent, missing a hydrogren at one part of carbon chain

example of polyunsaturated fat & descriptions of its structure

flaxseed oil, contains more than one double bond, straight carbon chain

which fatty acid contains its first double bond on 6th omega carbon

omega-6 fatty acid

what do omega-6 fatty acids help to do

helps to regulate the constriction of blood vessels

descriptions of omega-3

- includes the acids DHA and EPA
- is consumed in smaller quantities in human diet
- consumption reduces heart disease risk
- is known as alpha-linolenic acid

descriptions of omega-6

- higher ration in avacado and soybean oil
- meats are key food source

proteins

compounds composed of carbon, hydrogen, oxygen, and nitrogen atoms, arranged into amino acids linked in a chain

essential amino acids

amino acids that the body cannot synthesize in amounts sufficient to meet physiological needs

amino acids

building blocks of proteins; each contains an amino group, an acid group, a hydrogen atom, and a distinctive side group, all attached to a central carbon atom

conditionally essential amino acids

an amino acid that in normally nonessential, but must be supplied by the diet in special circumstances when the need for it exceeds the body's ability to produce it

peptide bond

a bond that connects the acid end of one amino acid with the amino acid of another, forming a link in a protein chain

dipeptide

two amino acids bonded together

tripeptide

three amino acids bonded together

polypeptide

many (10 or more) amino acids bonded together

hemoglobin

the globular protein of the red blood cells that carries oxygen from the lungs to the cells throughout the body

pepsin

a gastric enzyme that hydrolyzes protein; is secreted in an inactive form which is activated by hydrochloric acid in the stomach

proteases

enzymes that hydrolyze protein

peptidase

a digestive enzyme that hydrolyzes peptide bonds

transcription

the process of messenger RNA being made from a template of DNA

translation

the process of messenger RNA directing the sequence of amino acids and synthesis of proteins

sickle-cell anemia

a hereditary form of anemia characterized by abnormal sickle or crescent-shaped red blood cells; interfere with oxygen transport and blood flow

gene expression

the process by which a cell converts the genetic code into RNA and protein

matrix

the basic substance that gives form to a developing structure; in the body, the formative cells from which teeth and bones grow

collagen

the structural protein from which connective tissues such as scars, tendons, ligaments. and the foundations of bones and teeth are made

enzymes

proteins that facilitate chemical reactions without being changed in the process; protein catalysts

fluid balance

maintenance of the proper types and amounts of fluid in each compartment of the body fluids

edema

the swelling of body tissues caused by excessive amounts of fluid in the interstitial spaces

acids

compounds that release hydrogen ions in a solution

bases

compounds that accept hydrogen ions in a solution

buffers

compounds that keep a solution's pH constant when acids or bases are added

antigens

substances that elicit the formation of antibodies or an inflammation reaction from the immune system; ex: bacterium, virus, toxin, and protein in food that causes allergy

antibodies

large proteins of the blood and body fluids, produced by the immune system in response to the invasion of the body by foreign molecules

amino acid pool

the supply of amino acids derived from either food proteins or body proteins that collect in the cells and circulating blood and stand ready to be incorporated in proteins and other compounds or used for energy

nitrogen balance

the amount of nitrogen consumed as compared with the amount of nitrogen excreted in a given period of time

neurotransmitters

chemicals that are released at the end of a nerve cell when a nerve impulse arrives there; they diffuse across the gap to the next cell and alter the membrane of that second cell to either inhibit or excite it

deamination

removal of the amino group from a compound such as an amino acid

keto acid

an organic acid that contains a carbonyl group

transamination

the transfer of an amino group from one amino acid to a keto acid, producing a new nonessential amino acid and a new keto acid

photosynthesis

the process by which green plants use the sun's energy to make carbohydrates from carbon dioxide and water

metabolism

the sum total of all the chemical reactions that go on in living cells

anabolism

reactions in which small molecules are put together to build larger ones

catabolism

reactions in which large molecules are broken down to smaller ones

ATP (adenosine triphosphate)

a common high-energy compound composed of a purine, a sugar, and 3 phosphate groups

coupled reactions

pairs of chemical reactions in which some of the energy released from the breakdown of one compound is used to create a bond in the formation of another compound

coenzymes

complex organic molecules that work with enzymes to facilitate the enzymes' activity

pyruvate

a 3-carbon compound that plays a key role in energy metabolism

acetyl CoA

a 2-carbon compound to which a molecule of CoA is attached

TCA cycle (tricarboxylic acid cycle)

a series of metabolic reactions the break down molecules of acetyl CoA to carbon reactions and hydrogen atoms

electron transport chain

the final pathway in energy metabolism that transports electrons from hydrogen to oxygen and captures the energy released in the bonds of ATP

glycolysis

the metabolic breakdown of glucose to pyruvate; does not require oxygen

anaerobic

not requiring oxygen

aerobic

requiring oxygen

mitochondria

the cellular organelles responsible for producing ATP aerobically

lactate

a 3-carbon compound produced from pyruvate during anaerobic metabolism

Cori cycle

the pathway in which glucose is metabolized to lactate in the muscle, lactate is converted back to glucose in the liver, and then glucose is returned to the muscle

oxaloacetate

a carbohydrate intermediate of the TCA cycle

gluconeogenesis

the making of glucose from a noncarbohydrate source such as amino acids or glycerol

ketone bodies

compounds produces during the incomplete breakdown of fat when glucose is not available in the cells

keto acid

an organic acid that contains a carbonyl group

Energy balance

Energy (kcals) consumed compared with the energy expended through metabolic processes and physical activity

one pound of body fat equals

3500 kcals

Bomb calorimeter

an instrument that measures the heat energy released when food is burned (potential energy of food)

Physiological fuel value

number of calories that the body gets from food in contrast to the number of calories determined by calorimetry is

Satiation

feeling of fullness that a person experiences during a meal that halts eating (activated by cholecystokinin). Determines how much you eat

satiety

the feeling of fullness and satisfaction that occurs after a meal. Determines time between meals

Thermogenesis

heat released when body breaks down carbs, far or protein for energy. Used to measure the amount of energy expended

Basal metabolism

The energy needed to maintain life when body is at a complete digestive, physical, and emotional rest. 2/3 of energy expended goes to support Basal metabolism

thermic effect of food (TEF)

estimation of the energy required to process food (digest, absorb, transport, metabolize, and store ingested nutrients). Proportional to the food energy taken in, about 10% of energy intake.