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Macromolecules . Macromolecules. form the living organisms have: a carbon core base the core has attached groups of atoms called functional groups which confer specific chemical properties very large
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Macromolecules • form the living organisms • have: • a carbon core base • the core has attached groups of atoms called functional groups whichconfer specific chemical properties • very large • assembled from many small components, called monomers; the assembled chain of monomers is known as a polymer • polymers/monomers are dynamic structures depending on the needs of the cells by two reversible processes
There are four types of macromolecules: • Carbohydrates • Lipids • Proteins • Nucleic acids
Carbohydrates • a carbohydrate is any molecule that contains the elements C, H, and O in a 1:2:1 ratio • Important role in: • making up the structural framework of cells • energy storage • the sizes of carbohydrates varies • simple carbohydrates – made up of one or two monomers • complex carbohydrates– made up of polymers
Simple carbohydrates are small molecules made up of one or two monomers • monosaccharides consist of only one monomer • an example is the sugar glucose (C6H12O6) • disaccharides consist of two monosaccharides • an example is the sugar sucrose, which is formed by joining together two monosaccharides, glucose and fructose • the lactose is made up of two glucose molecules
Complex carbohydrates are long polymer chains and called polysaccharides • Plants and animals store energy in polysaccharide chains formed from glucose • plants form starch • animals form glycogen
Some polysaccharides are structural and resistant to digestion by enzymes • plants form cellulose cell walls • some animals form chitin for exoskeletons
Lipids • molecules are not soluble in water • lipids are non-polar molecules • lipids have many different types • fats • oils • Steroids • cholesterol • rubber • waxes • pigments
Fats are converted from glucose for long-term energy storage • have two subunits • fatty acids • glycerol • fatty acids are chains of C and H atoms, known as hydrocarbons
Because there are 3 fatty acids attached to a glycerol, another name for a fat is triglyceride
Fatty acids have different chemical properties due to the number of hydrogens attached • maximum number of hydrogens are attached, fat is saturated (bad fat for your body), they are solid at room temperature • there are fewer than the maximum attached, fat is unsaturated (the less number of hydrogens the better for your body), they are liquid at room temperature
cell membranes contain lipids • phospholipids make up the two layers of the membrane • cholesterol is embedded within the membrane
Fats are divided into three groups — • monounsaturated, • polyunsaturated • saturated. Monounsaturated Fats: • in foods that come from plants. • liquid at room temperature • can reduce blood cholesterol levels, but less than polyunsaturated fats do. • can raise HDL cholesterol (the "good" kind of cholesterol) levels. Polyunsaturated Fats: • mainly from plants. • liquid at room temperature. • can reduce blood cholesterol levels.
Saturated Fats: • animal origin food and some vegetables • in processed bakery goods, nondairy milk, cream substitutes. • Coconut Oil • Cocoa Butter (Chocolate) • Palm Kernel Oil, Palm Oil • As a rule of thumb when shopping, saturated fats are solid at room temperature. • When you have a lot of saturated fat in your diet, your liver responds by making more cholesterol. This raises your blood cholesterol level. It is the most harmful type of fat you can eat.
Hydrogenation / Trans Fats • hydrogen is bubbled through polyunsaturated and monounsaturated fats and oils to change from liquid to solid form • make vegetable margarines have a butter-like texture, and prolong the shelf life of packaged foods. • The effects: cause blood cholesterol levels to increase. • limit your use • manufacturers are not required to list how much trans fats are included in a product: Read the list of ingredients carefully
Saturated Beef Brazil Nuts, Macadamia Nuts Butter Cheese Chocolate Coconut, Coconut Oil Lard Milk Palm Oil Pistachios Poultry Polyunsaturated Almonds, pecans, Walnuts Corn Oil, Cottonseed Oil, Soybean Oil Fish Margarine Mayonnaise Sesame Seeds, Sesame Oil Sunflower Oil, Sunflower Seeds Monounsaturated • Avocado • OIL: Canola Oil, olive oil, sesame oil • Cashews • Olives • Peanuts, Peanut Butter, Peanut Oil
Proteins • are complex macromolecules/polymers made up by subunits called amino acids • the assembled polymer is called a polypeptide
Amino acids • are small molecules • 20 different types of amino acids
the covalent bond linking two amino acids together is called a peptide bond
Protein structure is complex • order or sequence of the amino acids affects how the protein folds together, • example the insulin molecule • the way that a polypeptide folds to form the protein determines the protein’s function • some proteins are comprised of more than one polypeptide
There are four general levels to protein structure • Primary • Secondary • Tertiary • Quaternary
Primary structure – • is the sequence of the amino acids in the polypeptide chain • This affects all other levels of protein structure
Secondary structure • forms because regions of the polypeptide that are non-polar are forced together • The folded structure may resemble • Coils • Helices • sheets
Tertiary structure – • final 3-D shape of the protein • The final twists and folds that lead to this shape are the result of polarity differences in regions of the polypeptide
Quaternary structure – • the spatial arrangement of proteins • comprised of more than one polypeptide chain
The shape of a protein affects its function: • changes to the environment of the protein may cause it to unfold or denature: • increased temperature or lower pH affects hydrogen bonding, which is involved in the folding process • a denatured protein is inactive
Enzymes • are globular proteins that have a special 3-D shape that fits precisely with another chemical • they cause the chemical that they fit with to undergo a reaction • this process of enhancing a chemical reaction is called catalysis
Nucleic Acids • are very long polymers that store information • There are two types of nucleic acids • Deoxyribonucleic acid (DNA) • Ribonucleic acid (RNA)
Nucleid acids are comprised of monomers called nucleotides (A, T, U, G, C) • each nucleotide has 3 parts • a five-carbon sugar • a phosphate group • a nitrogen-containing base • there are five different types of nucleotides whose sequence encodes genetic information
RNA is similar to DNA except that • it uses uracil instead of thymine • it is comprised of just one strand • it has a ribose sugar