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REVIEW: How many BONDS does each atom make?

Carbon: _____

Hydrogen: _____

Nitrogen: _____

Oxygen: _____

NUTRIENTS

• Chemicals that must be obtained from an

organism’s environment in order to survive

• Macronutrients include CARBOHYDRATES,

PROTEINS, and LIPIDS.

• Micronutrients include VITAMINS and MINERALS.

• Water is also an essential nutrient.

• Most macromolecules (carbohydrates and

proteins) are POLYMERS - long chain-like molecules

composed of repeating units called MONOMERS.

1. CARBOHYDRATES

- composed of carbon, hydrogen, and oxygen atoms, usually in ratio CH2OEx. C6H12O6

- most important source of energy

Comparing monosaccharides, disaccharides, polysaccharides:

1A. MONOSACCHARIDE (simple sugar)

• Examples: glucose, galactose, and fructose• found in fruits, honey, milk, and vegetables

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Examples of monosaccharides: Look at what a small difference can do!

Glucose Galactose

Drawing of MonosaccharidesPRACTICE (Glucose)

Drawing of MonosaccharidesPRACTICE (Galactose)

Drawing of MonosaccharidesPRACTICE (Fructose)

1B. DISACCHARIDE (double sugar)

• 2 monosaccharides bonded togetherEx: maltose (glu + glu), sucrose (glu + fru), lactose (glu + gala)

• found in beer, sugar cane, milk

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1B. DISACCHARIDE (double sugar) continued

• monosaccharides join to form a disaccharide in a

dehydration synthesis reaction.

• Example: formation of sucrose

Dehydration synthesis compared to Hydrolysis reactions… So dehydration synthesis reactions form polymers from monomers…

And HYDROLYSIS reactions break them apart!

Hydrolysis Dehydration Synthesis

Water is added Water is removed

Breaking down (digestion) Building/formation

Polymers into monomers Monomers into polymers

Ex. Disaccharides into monosaccharides

Ex. monosaccharides into disaccharides

1C. POLYSACCHARIDE (complex carbohydrate)

• hundreds to thousands of glucose subunits joined together

• four main types that differ in source, function, and structure

• starch – energy storage in plants

• glycogen – energy storage in animals (in liver and muscles)

• cellulose – structural polysaccharide produced in plant cell walls; humans cannot digest it so for us it is fibre

• chitin – structural polysaccharide found in the hard exoskeleton of insects and crustaceans used for contact lenses and surgical stitches

Humans cannot digest cellulose, but it provides fibre!

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1C. POLYSACCHARIDE (complex carbohydrate) continued

• Example: starch (glucose subunits joined together)

Also can be drawn like this:

2. LIPIDS

- hydrophobic macromolecules

- include fats, waxes, phospholipids, and steroids

- function as long-term nutrient and energy storage, insulation, cushioning for organs, and forms an integral part of hormones and cell membranes

Fats

- called triglycerides → the most common type of lipid

glycerol + 3 fatty acids → triglyceride + 3H2O

(dehydration synthesis - practice drawing below)

Triglyceride (structure of fats)Saturated have “all the hydrogen atoms they can fit”!Unsaturated have one or more double bonds in the chain

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- fatty acids can be the same or different, short or long, saturated (all single bonds) or unsaturated (double or triple bonds)

(PRACTICE drawing below)

- saturated fats come from animals and tend to be solid

at room temperature (ex. butter)

- unsaturated fats come from plants and tend to

be liquid at room temperature

(ex. olive oil)

Transfats: Unsaturated that behave like saturatedThey raise your bad cholesterol and lower your good cholesterol

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How does THAT make sense

???

Diagrammatic representation of fats: What makes an omega-3 fatty acid an omega-6 fatty acid?

Phospholipids- have a hydrophilic head with a phosphate group (polar, water-loving)

- have two hydrophobic tails which are fatty acids (non polar, water-fearing)

- important molecules in the cell membrane

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Steroids

- includes cholesterol and some sex hormones such as testosterone and estrogen

testosterone

Cholesterol

4 rings!

3. PROTEINS- the most diverse molecules in living organisms and among the most important

(ex. muscle, bone, skin, hair, nails, enzymes, hormones, antibodies, hemoglobin, cytochrome C)

- found in beef, poultry, fish, eggs- polymer of amino acids

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- the general structure of an amino acid:

(practice drawing below)

20 Amino Acids (9 are essential – cannot be made by our bodies):

A protein is made of many amino acids in a chain:

- amino acids are linked by a peptide bond in a dehydration synthesis reaction- a chain of amino acids is called a polypeptide

(practice drawing below)

Amino acid chain:

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Different interactions cause folding of the protein Protein Folding:

The result is a 3D shape!- polypeptides form primary, secondary, tertiary, and quaternary structures:

1o→ a strand of amino acids

2o→ folding of polypeptides into sheets or loops

(determined by the amino acid sequence)

3o→ 3D structure that forms when the sheets or

loops fold

4o→ 2 or more folded polypeptides joined together

to form functional protein

Your body is made of 55%-60% water

CytoplasmChemical reactionsDigest foodEliminate wasteMaintain blood volumeRegulate body tempKeep skin moist

DRINK 2L per day

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Fat: 1 gram = 9 calories

Protein: 1 gram = 4 calories

Carbohydrates: 1 gram = 4 calories

Alcohol: 1 gram = 7 calories