NUTRITION CARBOHYDRATES Carbohydrates are molecules made of carbon

NUTRITION

CARBOHYDRATES � Carbohydrates are molecules made of carbon, hydrogen, and oxygen.

MONOSACCHARIDES � The simplest carbohydrates are monosaccharides, also called simple sugars. � The number of carbon atoms found in monosaccharides can vary from anywhere between 3 to 7 carbon atoms.

MONOSACCHARIDES � Most have 6 carbons, like glucose with a formula of C 6 H 12 O 6. They also have names that end in –ose.

DISACCHARIDES � Two monosaccharides linked in a pair are a disaccharide. � Sucrose, or table sugar, is a disaccharide made up of 1 glucose molecule and 1 fructose molecule.

POLYSACCHARIDES � More than 2 monosaccharides connected in a chain is a polysaccharide, also called complex carbohydrates.

TYPES OF POLYSACCHARIDES � Starch – glucose molecules linked into a very long, linear chain. Plants use starch to store energy.

TYPES OF POLYSACCHARIDES � Glycogen – is a chain of glucose molecules with many branches.

� Glycogen is an energy-storage compound for animals. It is stored in the liver and is hydrolyzed when the body’s demand for sugar increases.

TYPES OF POLYSACCHARIDES � Cellulose – is also a chain of glucose molecules, similar to starch, but in a slightly different configuration.

� Cellulose has a structural function in plant’s cell walls. It is the most abundant organic molecule in the world. Humans can’t digest cellulose but it still plays an important role in our diet as fibre.

FATS � mmmmm

FATS � Like carbs they are mainly composed of carbon, oxygen, and hydrogen. � They may be oils, fats, or wax

� For each molecule of fat synthesized, 3 waters are produced. � Lipids are not water soluable do to long non-polar fatty acid tails

� Lipids group in water and will not mix � They are HYDROPHOBIC

SATURATED VS UNSATURATED � Carbon atoms always make 4 bonds. � If the fatty acid tail only contains single C-C bonds than the fat is saturated � Allows them to “align” and solidify easier. These are your fats that are solid at room temp � If the fatty acids contains double bonds than it is said to be unsaturated � Makes them more “rigid” and less malleable. Liquids at room temp

FUNCTIONS OF LIPIDS Lipids provide energy. 1 gram of fat will produce 9 calories while 1 gram carbohydrate will produce 4 calories. � Lipids are used in the structures of cell membranes. � Fat under the skin of animals prevents heat loss. � Fat cushions organs � Lipids are used to make important molecules in the body like hormones. � Plants use waxes on the surface of the leaf to prevent water loss. �

LIPIDS AND NUTRITION � Lipids are important for human nutrition because: � Lipids provide energy (more NRG per gram than carbs) � The human body requires lipids to make important biological compounds such as hormones. � Lipids are required for the body to process fat -soluble vitamins such as Vitamins A, D, E, and K.

CHOLESTEROL � Cholesterol is a lipid that many healthconscious people are concerned about. Cholesterol is important because it is a part of the cell membrane and is a precursor to many important molecules, such as hormones. However, high levels of cholesterol may contribute to fatty deposits in the arteries.

LOCK AND KEY THEORY

INDUCED-FIT THEORY