DE anatomy and physiology- Nutrition and metabolism

Nutrition

a study of how living organism obtain and utilize nutrients needed to grow and sustain life

Nutrients

include most biomolecules, vitamins, minerals, required for synthesis of new molecules, required for energy for maintenance, growth, repair, obtained through food, water

Macronutrients

must be consumed in relatively large quantities, needed in daily amounts, carbs, lipids, proteins, water

Micronutrients

Must be consumed in small quantities, vitamins and minerals

Essential

must be obtained from diet

Nonessential

provided by biochemical processes of body, not required in diet

Carbohydrates

4 cal/9, structurally classified as monosaccharides, disaccharides, polysaccharides (sugar, fruit, honey, grains,etc;)

gluconeogenesis

conversion of amino acids or lipids into glucose for metabolism by neurons, occurs when fasting

Lipids

9 cal/g, triglycerides (fatty acids), cholesterol

Saturated fatty acids

no double bond, sources are solid at room temperature, dietary sources:fat in dairy, oil

Unsaturated fatty acids

one double bond, sources are liquid at room temp, dietary sources: nuts, canola, olive, sunflower oils

Cholesterol

required as component of plasma membrane, precursor hormone for steroid hormones, bile, salts, vitamin d, comes from diet or metabolic pathway in liver

Proteins

4 cal/9, most structurally and functionally diverse molecules, needed in adequate quantities to replace worn out protein structures, of twenty types, 9 amino acids are essential, other 11 can be synthesized in the body

Complete proteins

contain all essential amino acids, generally animal proteins

Incomplete proteins

do not contain all essential amino acids, generally plant proteins

All or none rule for proteins

if any of the essential amino acids needed for protein production is missing, protein will not be made

Vitamins

organic molecules required for normal metabolism, present in only small amounts in food; essential a,b,c,d,e,k; nonessential NADH, FADH2

Water-soluble vitamins

dissolve in water and excess excreted in urine, b complex vitamins-essential for normal sugar metabolism , vitamin c- essential for tissue repair

fat soluble vitamins

vitamins a,d,e,k; excess stored in fat, may become toxic if taken in excess

Minerals

inorganic ions obtained from diet, required in daily amounts

Iron-trace mineral

in hemoglobin, binds oxygen

calcium and phosphorus-major minerals

required for formation and maintenance of skeleton and muscle contraction, blood clotting, and exocytosis of neurotransmitters

sodium and potassium- major minerals

maintain resting membrane potential in excitable cells, required to generate action potential

Glycolysis

anaerobic metabolic pathway in cytoplasm, glucose oxidized to 2 pyruvate molecules, 2 atp formed, 2 NADH formed from NAD+, pyruvate converted to lactate if insufficient 02 available

Intermediate stage (acetyl coa conversion)

this and following steps, aerobic and within the mitochondria, pyruvate converted to acetyl CoA, C02 formed and NADH produced

Citric acid cycle

Acetyl CoA forms citric acid, C02, ATP, FADH2 and NADH produced in cycle turn

electron transport system

transfer of hydrogen and electron from NADH and FADH2, ATP and water formed through oxidative phosphorylation, produces the highest amount of ATP of all 4 stages

Glycerol and fatty acids

building blocks of triglycerides, glycerol enters pathway of glycolysis

Amino acids

amine group of amino acids removed by deamination, amine group converted to urea, eliminated through kidney in urine

absorptive state

occurs after a meal when your body is digesting the food and absorbing the nutrients during meal and up to 4 hours afterwards, anabolism exceeds catabolism

postabsorptive state

the fasting state, catabolism exceeds anabolism

Hyperthermia

increase of body temperature above 100, differs from fever in that it is not caused by the hypothalamus, heat production exceeds body’s cooling mechanisms

heat stroke

extreme form of hyperthermia

Hypothermia

decrease of body temperature below 95, results when heat loss exceeds heat production

Gangrene

cell necrosis due to insufficient body supply, often due to atherosclerosis, diabetes, or frostbite, wet gangrene is accompanied by infection, may lead to sepsis, death

Vitamin B

essential for normal sugar and metabolism

Vitamin C

essential for tissue repair and the production of certain neurotransmitters

Vitamin A

precursor of visual pigment retinal

Vitamin D

forms calcitrol, increases calcium absorption from GI tract

Vitamin E

stabilizes and prevents damage to cell membranes

Vitamin K

required for synthesis of blood clotting proteins