Nutrition, Metab, and energy balance

nutrient

A substance in food used for energy, growth, maintenance, and repair of body tissues.

Essential Nutrient

A nutrient the body cannot synthesize in adequate amounts and must obtain from the diet.

Kilocalorie

a unit of energy equal to 1,000 calories

Pectin

can get from apples

Carbohydrates Primary Fuel Molecule

Glucose

Cells highly dependent on glucose:

Brain cells and red blood cells

Storage form of glucose

Glycogen (stored in liver and muscles)

Soluble fiber

dissolves in water, helps lower cholesterol and regulate blood sugar

Insoluble fiber

increases stool bulk and promotes bowel movement

Saturated fats

no double bonds, usually solid at room temperature

Unsaturated fats

one or more double bonds, usually liquid

Essential fatty acids

body cannot synthesize (ex: omega-3 and omega-6)

Functions of triglycerides

(most abundant) Energy storage, insulation, protection of organs, and energy source

Functions of cholesterol

Component of cell membranes; precursor for steroid hormones, bile salts, and vitamin D.

complete proteins

contain all essential amino acids

incomplete proteins

proteins that lack one or more of the essential amino acids

Positive nitrogen balance occurs during what

Growth, pregnancy, tissue repair, and muscle building.

Negative nitrogen balance occurs during:

Illness, infection, trauma, starvation, or protein deficiency.

Water-soluble vitamins:

Vitamin C and B-complex vitamins.

Fat-soluble vitamins:

Vitamins A, D, E, and K.

General function of vitamins:

help enzymes carry out metabolic reactions.

Why are fat-soluble vitamins more likely to cause toxicity?

stored in body fat and the liver, allowing them to accumulate.

Iron function

transport oxygen in blood.

Iodine function

thyroid hormone production.

Anabolism

build larger molecules from smaller ones, requiring energy.

Catabolism

break down molecules to release energy.

Oxidation

Loss of electrons.

Reduction

Gain of electrons.

Why are B vitamins critical in metabolism?

carry electrons during metabolic reactions.

Substrate-level phosphorylation occurs in:

Glycolysis and the citric acid cycle.

Oxidative phosphorylation occurs in:

The mitochondria

Role of leptin:

Signals the brain that body fat stores are sufficient and reduces appetite.

Role of ghrelin:

Hormone that stimulates hunger.

A nutrient is best defined as:***

a substance used for growth, maintenance, and repair

Glucose is primarily stored in the body as:***

glycogen

Insoluble fiber primarily:***

increases stool bulk

Cholesterol is important as a precursor for:***

steroid hormones

Negative nitrogen balance occurs during:***

infection or stress

Which vitamin requires intrinsic factor for absorption?***

Vitamin B12

Metabolism refers to:***

all biochemical reactions in the body

NAD+ becomes reduced to:***

NADH

Glycolysis yields a net of how many ATP per glucose?***

2

A patient with severe liver failure may develop hypoglycemia because the liver cannot:***

perform gluconeogenesis

A marathon runner experiencing muscle burning is accumulating:***

lactate

iron is essential for:***

Hemoglobin formation