NutritionNutrition

In order for the human body to be healthy In order for the human body to be healthy and resistant to disease, good nutrition is and resistant to disease, good nutrition is required. All living things are made of required. All living things are made of chemicals. In order to grow, develop and chemicals. In order to grow, develop and maintain bodily structures and functions, maintain bodily structures and functions, specific chemicals must be acquired from specific chemicals must be acquired from the food we eat. In a sense, the food we eat. In a sense, we are what we are what we eatwe eat. Nutrients can be divided into the . Nutrients can be divided into the following categories:following categories:

Nutrients OverviewNutrients Overview

CarbohydratesCarbohydrates – sugar based molecules that are – sugar based molecules that are metabolized for energy in cellular respiration and make up metabolized for energy in cellular respiration and make up the structural components of plant cell walls.the structural components of plant cell walls.

LipidsLipids – fat based molecules that store large quantities of – fat based molecules that store large quantities of energy. These molecules also make up the structure of energy. These molecules also make up the structure of cell membranes.cell membranes.

ProteinsProteins – polypeptide molecules that can store energy, – polypeptide molecules that can store energy, although their primary function is to provide the structural although their primary function is to provide the structural building blocks for cells and to make enzymes.building blocks for cells and to make enzymes.

Vitamins Vitamins – organic molecules that help mediate enzyme – organic molecules that help mediate enzyme action by promoting the binding of an enzyme to a action by promoting the binding of an enzyme to a substrate. These are also called substrate. These are also called coenzymes.coenzymes.

MineralsMinerals – inorganic molecules that mediate enzyme – inorganic molecules that mediate enzyme activities by promoting the binding of an enzyme to a activities by promoting the binding of an enzyme to a substrate. These are also called substrate. These are also called cofactors.cofactors.

Chemistry of Living ThingsChemistry of Living Things

Proteins-make the structural components of cells-make enzymes

Fats and Lipids-energy storage compounds, insulation, warmth-structural components of cell membranes

Nucleic Acids-form the genetic material of cells-make up ATP energy molecules

Vitamins and Minerals-found in complex chemicals-help mediate chemical reactions

CarbohydratesCarbohydrates --primary primary energyenergy sourcesource-structural material -structural material of cell wallsof cell walls

Chemicals of Life

General Types of MoleculesGeneral Types of Molecules

PolymersPolymers – are compounds made up of two or – are compounds made up of two or more (many) subunits, which are often joined by more (many) subunits, which are often joined by dehydration synthesisdehydration synthesis..

MonomersMonomers – are compounds made up of single – are compounds made up of single subunits, which can be produced by the subunits, which can be produced by the hydrolysishydrolysis of polymers. of polymers.

Dehydration Synthesis-HydrolysisDehydration Synthesis-Hydrolysis

CarbohydratesCarbohydrates

Names usually have an ‘Names usually have an ‘oseose ending ending

Are either single unit sugar molecules called Are either single unit sugar molecules called monosaccharidesmonosaccharides, two unit sugar molecules , two unit sugar molecules called called disaccharidesdisaccharides, or multiple unit sugar , or multiple unit sugar molecules called molecules called polysaccharidespolysaccharides. All sugar . All sugar molecules are made up of subunits with either a molecules are made up of subunits with either a 6 ring (hexose) base structure or a 5 ring 6 ring (hexose) base structure or a 5 ring (pentose) base structure.(pentose) base structure.

Have the formula ratio of Have the formula ratio of CC11HH22OO11. For example, . For example,

glucose is Cglucose is C66HH1212OO66

MonosaccharidesMonosaccharides

Are simple single sugars compounds composed of 5 Are simple single sugars compounds composed of 5 unit monomers (pentoses) or 6 unit polymers (hexoses)unit monomers (pentoses) or 6 unit polymers (hexoses)

Main Types of MonosaccharidesMain Types of Monosaccharides1) 1) Glucose:Glucose: The main monosaccharide. Needed The main monosaccharide. Needed for Cellular Respiration!for Cellular Respiration!

2) 2) Fructose: Fructose: a simple sugar often found in fruits a simple sugar often found in fruits – Fructose and Glucose are Fructose and Glucose are isomersisomers of each other, of each other,

which means that they have the same molecular which means that they have the same molecular formula, but different structural arrangementformula, but different structural arrangement

3)3) Galactose Galactose: a simple sugar found in dairy : a simple sugar found in dairy productsproducts

4) 4) Ribose:Ribose: genetic sugar, helps make RNA genetic sugar, helps make RNA

5) 5) Deoxyribose:Deoxyribose: genetic sugar, helps make genetic sugar, helps make DNADNA

DisaccharidesDisaccharidesDisaccharides and polysaccharides are created from Disaccharides and polysaccharides are created from monomers by a process called monomers by a process called dehydration synthesisdehydration synthesis or or dehydrolysisdehydrolysis. In this process, water molecules are . In this process, water molecules are removed, as a saccharide bond is formed.removed, as a saccharide bond is formed.

Main types of DisaccharidesMain types of Disaccharides(2 monosaccharides joining up)(2 monosaccharides joining up)

1) 1) SucroseSucrose: a : a glucoseglucose and a and a fructosefructose sugar molecule joining togethersugar molecule joining together

2) 2) MaltoseMaltose: 2 : 2 glucoseglucose molecules joining molecules joining togethertogether

3) 3) LactoseLactose: A : A glucoseglucose and a and a galactosegalactose molecule joining togethermolecule joining together

PolysaccharidesPolysaccharides

When many subunits join together by dehydration When many subunits join together by dehydration synthesis, a synthesis, a polysaccharidepolysaccharide ( (complex carbohydratecomplex carbohydrate) such ) such as as glycogenglycogen, , amylose (starch)amylose (starch) or or cellulosecellulose is produced. is produced.

stored glucose in plants

found in cell walls of plants. Can not be digested in Humans

stored glucose in animals

Tests for CarbohydratesTests for Carbohydrates Benedicts testBenedicts test – detects reducing sugars (all – detects reducing sugars (all monosaccharidesmonosaccharides and some disaccharides). and some disaccharides). The benedicts reagent turns from blue (little The benedicts reagent turns from blue (little amount) to amount) to orange/redorange/red (a lot) when reducing (a lot) when reducing sugars are present.sugars are present.Starch testStarch test – detects the presence of – detects the presence of complex complex carbohydratescarbohydrates (polysaccharides)(polysaccharides) or starch. or starch. Iodine is added and creates a Iodine is added and creates a blue-blackblue-black iodine iodine starch complex.starch complex.

LipidsLipids

Are Are non-polarnon-polar (and thus water insoluble), high energy (and thus water insoluble), high energy molecules composed of molecules composed of glycerolglycerol and and fatty acidsfatty acids. . Like carbohydrates, these two molecules combine by Like carbohydrates, these two molecules combine by dehydration synthesis.dehydration synthesis.These actually contain 2X the amount of energy per These actually contain 2X the amount of energy per gram as Carbs, but are not the primary source of gram as Carbs, but are not the primary source of energy due to being very hard to breakdownenergy due to being very hard to breakdown

Glycerol

Structure of a Lipid (Triglyceride)Structure of a Lipid (Triglyceride)All triglycerides have a All triglycerides have a glycerol glycerol backbonebackbone (that is always the same) and (that is always the same) and 3 3 fatty acidsfatty acids attached. The fatty acids are attached. The fatty acids are what differ among different types of what differ among different types of triglycerides.triglycerides.

1)Saturated Fats (fats, 1)Saturated Fats (fats, greasegrease, , lardslards))

fatty acid molecules that fatty acid molecules that have have nono double bonds in double bonds in the carbon chain. These the carbon chain. These molecules have as many molecules have as many hydrogen atoms as they hydrogen atoms as they can hold. They are can hold. They are solidsolid at room temperature and at room temperature and relatively unreactive relatively unreactive (difficult to digest).(difficult to digest).

Can lead to heart failure Can lead to heart failure and and atherosclerosisatherosclerosis (clogging of arteries)(clogging of arteries)

Usually come from animal products

2) Unsaturated Fats (Oils)2) Unsaturated Fats (Oils) fatty acid molecules that fatty acid molecules that have one or more have one or more double double bondsbonds in the carbon chain. in the carbon chain. Additional hydrogen Additional hydrogen atoms can be added to atoms can be added to these molecules. They are these molecules. They are liquidliquid at room temperature at room temperature and are more reactive, so and are more reactive, so they can be broken down they can be broken down more easily.more easily.

Can reduce heart Can reduce heart problems!!problems!!

Usually come from plant products

Other types of LipidsOther types of Lipids

3) 3) Phospholipids:Phospholipids: needed in cell needed in cell membranesmembranes

4) 4) WaxesWaxes

5) 5) Cholesterols:Cholesterols: HDLs and LDLs. HDLs and LDLs. see see readingreading

6) 6) Steroids:Steroids: hormones, similar to hormones, similar to cholesterol, help muscle growth and cholesterol, help muscle growth and repair.repair.

Tests for LipidsTests for Lipids

Translucence testTranslucence test – – lipids cause unglazed lipids cause unglazed brown paper to brown paper to become become translucenttranslucent. . Non-lipids do not.Non-lipids do not.

Sudan IV testSudan IV test – lipids – lipids dissolve in the sudan dissolve in the sudan IV indicator turning it IV indicator turning it from a black granular from a black granular form to a form to a pink or red pink or red paste.paste.

ProteinsProteins

Are polymers made up of Are polymers made up of combinations of 20 combinations of 20 different different amino acidamino acid subunits joined together by subunits joined together by dehydration synthesisdehydration synthesis. . Amino acids are held Amino acids are held together by together by peptide peptide bondsbonds. Proteins form . Proteins form structural components of structural components of cells and enzymes, and cells and enzymes, and they store useful energy.they store useful energy.

Protein Primary StructureProtein Primary StructureAll amino acids have a basic All amino acids have a basic amino group and a carboxylic amino group and a carboxylic acid. Different amino acids acid. Different amino acids have different R groups or have different R groups or side chains. There are 20 side chains. There are 20 different amino acids in total.different amino acids in total.Proteins are formed from Proteins are formed from long chains of amino acids long chains of amino acids that are joined together by that are joined together by peptide bonds. These bonds peptide bonds. These bonds form from a dehydration form from a dehydration synthesis reaction. synthesis reaction.

Protein Secondary StructureProtein Secondary Structure

hydrogen bonds cause proteins to fold into hydrogen bonds cause proteins to fold into pleated sheets, or coil into helixes. pleated sheets, or coil into helixes.

Protein Tertiary StructureProtein Tertiary Structure further folding of a polypeptide creates a further folding of a polypeptide creates a larger globular structure, such as that found in larger globular structure, such as that found in the hemoglobin groups in red blood cells.the hemoglobin groups in red blood cells.

Quaternary StructureQuaternary Structure

are large are large globular proteins globular proteins formed form two formed form two or more or more interacting interacting polypeptides.polypeptides.

Tests for ProteinsTests for Proteins Biuret Test – Biuret Test – when the blue biuret when the blue biuret reagent is added to proteins, the reagent is added to proteins, the peptide bonds turn the biuret reagent a peptide bonds turn the biuret reagent a purple colorpurple color. .

When exposed to excessive heat, When exposed to excessive heat, radiation or changes in pH, the radiation or changes in pH, the hydrogen bonds that hold proteins hydrogen bonds that hold proteins together break down, disrupting the together break down, disrupting the configuration/shape of the protein. This configuration/shape of the protein. This process is called process is called protein denaturationprotein denaturation. . When the change is irreversible, the When the change is irreversible, the process is called process is called coagulation.coagulation. Boiling Boiling an egg, or cooking meat is an example an egg, or cooking meat is an example of this.of this.

EnzymesEnzymesCatalysts Catalysts – are chemicals – are chemicals that increase the rate of that increase the rate of chemical reactions and chemical reactions and allow reactions to occur at allow reactions to occur at lower temperature, without lower temperature, without being used themselves. being used themselves.

Catalysts provide an alternate reaction pathway, thus decreasing the energy (temperature) required for the reaction to take place.

EnzymesEnzymes

are protein catalysts found within living organisms. All are protein catalysts found within living organisms. All enzymes have an enzymes have an active site,active site, or area where the or area where the substrate substrate (what is being reacted) binds to the enzyme.(what is being reacted) binds to the enzyme.

Enzyme activityEnzyme activity

Factors Affecting Enzyme ReactionsFactors Affecting Enzyme Reactions

pH pH – specific enzymes – specific enzymes function best within a function best within a specific range of pH. specific range of pH. For example, enzymes For example, enzymes in your blood function in your blood function best at a pH of about best at a pH of about 7.2-7.4. Enzymes in 7.2-7.4. Enzymes in your stomach function your stomach function best at a pH of about best at a pH of about 1.0. If the pH is too low 1.0. If the pH is too low or too high, the enzyme or too high, the enzyme may denaturemay denature..

Substrate concentrationSubstrate concentration – – higher the substrate higher the substrate concentrations usually concentrations usually produce greater enzyme produce greater enzyme activity until all of the active activity until all of the active sites are occupied.sites are occupied.

Temperature Temperature – increased – increased temperatures increase temperatures increase enzyme activity until the enzyme activity until the enzyme starts to denature. enzyme starts to denature. Very high temperature break Very high temperature break down proteins, and render the down proteins, and render the enzymes ineffective.enzymes ineffective.

Competitive InhibitorsCompetitive Inhibitors molecules that have a shape similar to the substrate and binds molecules that have a shape similar to the substrate and binds to the active site of an enzyme, preventing the desired reaction. to the active site of an enzyme, preventing the desired reaction. CO is a competitive inhibitor to the binding of oxygen.CO is a competitive inhibitor to the binding of oxygen.

Regulation of Enzyme ActivityRegulation of Enzyme Activity Feedback Inhibition –Feedback Inhibition – is is the inhibition of an the inhibition of an enzyme by the final product in the metabolic enzyme by the final product in the metabolic pathway.pathway.

Precursor ActivityPrecursor Activity - is the activation of the last - is the activation of the last enzyme in a metabolic pathway, by the initial enzyme in a metabolic pathway, by the initial substrate.substrate.

Allosteric ActivityAllosteric Activity – is the change in an enzyme – is the change in an enzyme caused by the binding of a molecule. This may caused by the binding of a molecule. This may promote or prevent enzyme activity. promote or prevent enzyme activity.

BIOL 230 Lecture Guide - Animation of BIOL 230 Lecture Guide - Animation of Noncompetitive Inhibition with Allosteric Noncompetitive Inhibition with Allosteric EnzymesEnzymes

Co-factorsCo-factors – are inorganic ions that help – are inorganic ions that help enzymes combine with substrate molecules. enzymes combine with substrate molecules. These come from mineral supplements. Ex. These come from mineral supplements. Ex. iron helps oxygen bind to hemoglobin.iron helps oxygen bind to hemoglobin.

http://www.facsup.armstrong.edu/http://www.facsup.armstrong.edu/videoproduction/exmedia/Instruct1.swfvideoproduction/exmedia/Instruct1.swf

Co-enzymesCo-enzymes – are organic molecules that – are organic molecules that help enzymes combine with substrate help enzymes combine with substrate molecules. These come from vitamins.molecules. These come from vitamins.