Main Points

liver

Absorbed monosaccharides other than glucose are converted to glucose by the ___?

cellular fuel

Monosaccharides are used primarily for __?

carbohydrate

Recommended intake for adults is 45-65% of daily caloric intake.

triglycerides

Most dietary lipids are ___?

egg yolk, meats, and milk products

The major sources of cholesterol are __?

animal products, tropical oils, and hydrogenated oils

The primary sources of saturated fats are __?

plant products, nuts, and cold-water fish

Unsaturated fats are present in __?

essential fatty acids

Linoleic (omega-6) and linolenic (omega-3) acids are ___?

Triglycerides

______ provide reserve energy, cushion body organs, and insulate the body.

plasma membranes and myelin

Phospholipids are used to synthesize ___?

Cholesterol

______ is the structural basis of vitamin D, steroid hormones, and bile salts.

Fat

intake be limited to 20-35% of caloric intake

mono- and polyunsaturated fats

saturated and trans fats should be replaced by ___?

Vitamins

______ are organic compounds needed in minute amounts.

whole grains, vegetables, legumes, and fruit.

richest sources of vitamins are ___?

meats, vegetables, nuts, and legumes.

The richest sources of minerals are some __?

maintain life

Metabolism encompasses all chemical reactions necessary to ___?

anabolic or catabolic.

Metabolic processes are either ___?

Cellular respiration

_______ refers to catabolic processes during which energy is released and some is captured in ATP bonds.

are oxidized

Energy is released when organic compounds ___?

removing hydrogen (or electrons)

Cellular oxidation is accomplished primarily by ___?

coenzymes as hydrogen acceptors

Most enzymes catalyzing oxidation-reduction reactions require ____?

NAD+ and FAD.

Two important coenzymes in these reactions are

substrate-level and oxidative phosphorylation.

In animal cells, the two mechanisms of ATP synthesis are ___?

glucose metabolism

Carbohydrate metabolism is essentially ___?

glycolysis, citric acid cycle, and electron transport chain.

Glucose is oxidized to carbon dioxide and water via three successive pathways:

electron transport chain.

Some ATP is harvested in each pathway, but the bulk is captured in the ___?

citric acid cycle , lactic acid

Under aerobic conditions, pyruvic acid enters the ______; under anaerobic conditions, it is reduced to _______.

2 molecules of NADH, net gain of 2 ATP

glucose is converted to two pyruvic acid molecules;

pyruvic acid (and fatty acids)

The citric acid cycle is fueled by ____?

acetyl CoA.

To enter the citric acid cycle, pyruvic acid is converted to ____?

delivering hydrogen to a series of oxidation-reduction acceptors

In the electron transport chain, reduced coenzymes are oxidized by ___?

hydrogen ions and electrons

In the electron transport chain hydrogen is split into ___?

H+ back through ATP synthase, which uses the energy to form ATP

In electron transport chain the energy stored in the electrochemical proton gradient drives ___?

form water.

In electron transport chain H+ and electrons are combined with oxygen to __?

32 ATP. 4 ATP from substrate-level phosphorylation and 28 ATP from oxidative phosphorylation.

For each glucose molecule oxidized to carbon dioxide and water, there is a net gain of ___?

inhibited and glucose is converted to glycogen.

When cellular ATP reserves are high, glucose catabolism is ___?

glycogenolysis occurs

When blood glucose levels begin to fall ___?

chylomicrons

End products of lipid digestion are transported in blood in the form of ___?

glyceraldehyde 3-phosphate

Glycerol is converted to __?

beta oxidation into acetic acid fragments

Fatty acids are oxidized by __?

acetyl CoA

acetic acid fragments enter the citric acid cycle as __?

adipose tissue

Dietary fats not needed for energy or structural materials are stored in __?

lipolysis

Breakdown of fats to fatty acids and glycerol is called __?

fat depots

There is a continual turnover of fats in __?

ketone bodies

When excessive amounts of fats are used, the liver converts acetyl CoA to __?

metabolic acidosis

Excessive levels of ketone bodies (ketosis) leads to ___?

build their plasma membranes

All cells use phospholipids and cholesterol to ____?

Ketone bodies

Metabolic byproducts formed from acetyl CoA during fat metabolism; excessive levels can lead to ketosis and metabolic acidosis.

Phospholipids

Lipids that are a major component of cell membranes, alongside cholesterol.

Amino acids

Organic compounds that serve as the building blocks of proteins; they are crucial for various bodily functions.

Nonessential amino acids

Amino acids that can be synthesized by the body; they do not need to be obtained from the diet.

Glycogenolysis

The process of breaking down glycogen into glucose, which occurs during the postabsorptive state.

Gluconeogenesis

The metabolic pathway through which glucose is synthesized from non-carbohydrate precursors.

Liver

The body's main metabolic organ, crucial for processing, storing nutrients, and detoxifying substances.

Cholesterol

A lipid molecule that is essential for forming cell membranes and is synthesized by the liver.

Obesity

A condition characterized by excessive fat storage, indicated by a Body Mass Index (BMI) over 30.

Essential amino acids

Amino acids that must be obtained from the diet because the body cannot synthesize them.