after students complete the ph lab, they will have a basic understanding of which substances are...
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After students complete the pH lab, they will have a basic understanding of which substances are classified as acids or bases as recorded in the pH Lab Data table. Students will also observe and be able to describe the reaction between an acid and a base when they are added together.
After discussing what carbohydrates are and looking at the molecular models in the power point, students will identify simple and complex carbohydrates by stating which foods contain them.
Contains carbon(Carbon dioxide & carbon monoxide contain carbon, but they are inorganic)
Carbon is electroneutralMeans it never loses or gains electrons, it always shares
Contain carbon, hydrogen, and oxygen
Includes sugars and starches Their major function is to supply a
source of cellular food Classified as monosaccharides (one
sugar), disaccharide (two sugars), and polysaccharide (many sugars)
Figure 2.13a
Monosaccharides or simple sugars
Monosaccharides are the building blocks of all other carbohydrates
Figure 2.13a
Important polysaccharides to the body – starch and glycogen – both are polymers of glucose
StarchStorage carbohydrate of plants
GlycogenStorage carbohydrate of animalsStored in muscles and the liverWhen blood sugar levels drop, liver cells
break down glycogen and release glucose into the blood
After discussing what carbohydrates are, looking at the molecular models in the power point, and performing the starch lab, students will identify simple and complex carbohydrates, and state which foods contain them. Students will be able to test for the presence of starch in foods.
After discussing what carbohydrates are, looking at the molecular models in the power point, and performing the starch lab, and Simple sugar lab students will identify simple and complex carbohydrates, and state which foods contain them. Students will be able to test for the presence of starch and simple sugars in foods.
After discussing what lipids are and looking at the molecular models in the power point, students will identify lipids and state which foods contain them. Students will be able to explain why lipids are important to our bodies.
Insoluble in water Contain C, H, and O, but the
proportion of oxygen in lipids is less than in carbohydrates
Examples:Neutral fats or triglyceridesOils PhospholipidsSteroidsWaxes
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Fats store energy, help to insulate the body, and cushion and cushion and protectprotect organs organs
Oils (liquid) unsaturated fat
Fats (solid) Saturated fat
Waxes Prevents water loss in plants
Earwax
Phospholipids found in cell membranes
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Unsaturated fatty acids have less than the maximum number of hydrogens bonded to the carbons (a double bond between carbons)
Saturated fatty acids have the maximum number of hydrogens bonded to the carbons (all single bonds between carbons)
Body’s most efficient form for storing large amounts of usable energy
Found mainly beneath the skin and around organs Insulates deeper body tissues from heat loss and
protects from trauma
Figure 2.14a
Women usually have a thicker subcutaneous fatty layer (more insulation) than men – why women are more successful English Channel swimmers
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Most animal fats have a high proportion of saturated fatty acids & exist as solids at room temperature (butter, margarine, shortening)
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Most plant oils tend to be low in saturated fatty acids & exist as liquids at room temperature (oils)
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• Cell membranes are made of lipids called phospholipids
• Phospholipids have a head that is polar & attract water (hydrophilic)
• Phospholipids also have 2 tails that are nonpolar and do not attract water (hydrophobic)
Phospholipids – modified triglycerides with two fatty acid groups and a phosphorus group
Figure 2.14b
Amphipathic – has both polar and nonpolar parts Chief component of cell membranes Nonpolar hydrocarbon portion (tail) interacts with only other nonpolar
molecules Phosphorus part is polar and attracts polar or charged particles like
water and ions
Cholesterol is the structural basis for all the body’s steroidsFound in cell membranesRaw material of vitamin D, bile salts, sex hormones, and adrenal cortical hormones.
Estrogen & testosterone are steroids
Figure 2.14c
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They are variants of testosterone
Some athletes use them to build up their muscles quicklyThey can pose serious health risks
Eicosanoids – 20-carbon fatty acids found in cell membranes – most important is the prostaglandins which has a role in blood clotting, inflammation, and labor contractions
Fat-soluble vitamins – vitamins A, E, and K
Lipoproteins which transport fatty acids and cholesterol in the bloodstream Figure 2.14c
trans·lu·cent/transˈlo#osnt/ Adjective: (of a substance)
Allowing light, but not detailed images, to pass through;
semitransparent.
After discussing what proteins are and looking at the molecular models in the power point, students will be able to identify proteins, state which foods contain them, describe their functions and state their building blocks. Students will also be able to explain the function of enzymes.
Basic structural material of the body Other proteins play vital roles in cell
function Proteins include
EnzymesHemoglobinContractile proteins of the muscle
All proteins contain carbon, oxygen, hydrogen, and nitrogen, many contain sulfur and phosphorus
Amino acids are the building blocks of protein, contains an amino group and a carboxyl group
20 common types of amino acids
Proteins are long chains of amino acids joined together by dehydration synthesis, resulting in a peptide bond
Most proteins are large molecules containing from 100 to 10,000 amino acids!
Figure 2.16
Primary – amino acid sequence Secondary – alpha helices or beta
pleated sheets Tertiary – superimposed folding of
secondary structures Quaternary – polypeptide chains
linked together in a specific manner
Fibrous proteinsExtended and strandlike proteins
Examples: keratin, elastin, collagen, and certain contractile fibers
Globular proteins Compact, spherical proteins with tertiary and quaternary structures
Examples: antibodies, some hormones, and enzymes
Irreversibly denatured proteins cannot refold and are formed by extreme pH or temperature changes
Figure 2.18b
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Changes in temperature & pH can denature (unfold) a protein so it
no longer worksCooking denatures protein in eggs
Milk protein separates into curds & whey when it denatures
Help other proteins to achieve their functional three-dimensional shape
Maintain folding integrity Assist in translocation of
proteins across membranes Promote the breakdown of
damaged or denatured proteins
Most are globular proteins that act as biological catalysts
Some enzymes are pure protein, some have a cofactor, usually a metal ion or an organic molecule derived from vitamins
Enzymes are chemically specific
Frequently named for the type of reaction they catalyze
Enzyme names usually end in -ase Lower activation energy
Enzyme-substrate
complex (E–S)
1
2
3
Internal rearrangements leading to catalysis
Free enzyme (E)
Active site
Enzyme (E) Substrates (s)
Amino acids
H20
Peptide bond
Dipeptide product (P) Figure 2.20
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• Blood sugar level is controlled by a protein called insulin
• Insulin causes the liver to uptake and store excess sugar as Glycogen
• The cell membrane also contains proteins
• Receptor proteins help cells recognize other cells
After discussing what nucleic acids are and looking at the molecular models in the power point, students will identify them, their building blocks and explain the importance of nucleic acids in our bodies and how they function.
Composed of carbon, oxygen, hydrogen, nitrogen, and phosphorus
Their structural unit, the nucleotide, is composed of Nitrogen-containing base, a pentose sugar, and a phosphate group
Five nitrogen bases contribute to nucleotide structure – adenine (A), guanine (G), cytosine (C), thymine (T), and uracil (U)
Two major classes – DNA and RNA DNA has the bases A, G, C, &T. RNA has the bases A, G, C, & U.
Double-stranded helical molecule found in the nucleus of the cell
Replicates itself before the cell divides, ensuring genetic continuity
Provides instructions for protein synthesis
Single-stranded molecule found in both the nucleus and the cytoplasm of a cell
Uses the nitrogenous base uracil instead of thymine
Three varieties of RNA: messenger RNA, transfer RNA, and ribosomal RNA
Source of immediately usable energy for the cell
Adenine-containing RNA nucleotide with three phosphate groups