Biological (Organic) Biological (Organic) MoleculesMolecules

Major Components of a Major Components of a CellCell

CarbohydratesCarbohydrates ProteinsProteins LipidsLipids Nucleic AcidsNucleic Acids

MoleculesMolecules

Organic molecules: contain Organic molecules: contain carboncarbon

Water is the most abundant Water is the most abundant molecule in cellsmolecule in cells

Minerals are considered trace Minerals are considered trace elements and are not needed in elements and are not needed in large amounts to sustain lifelarge amounts to sustain life

CarbohydratesCarbohydrates

Provide energy to cellsProvide energy to cells Consist of atoms of carbon, hydrogen Consist of atoms of carbon, hydrogen

and oxygenand oxygen– Usually twice as many hydrogen as Usually twice as many hydrogen as

oxygen atomsoxygen atoms CC66HH1212OO66 glucose glucose CC1212HH2222OO1111 sucrose sucrose

Simple sugars: monosaccharidesSimple sugars: monosaccharides Complex carbohydrates: disaccharides Complex carbohydrates: disaccharides

or polysaccharidesor polysaccharides

MonosaccharidesMonosaccharides

Simple sugarsSimple sugars Easily broken down for energyEasily broken down for energy To test for simple sugars – use To test for simple sugars – use

benedict’s reagentbenedict’s reagent (turns from (turns from blue to orange in the presence of blue to orange in the presence of glucose)glucose)

PolysaccharidesPolysaccharides

Complex sugarsComplex sugars Examples: starch, glycogen, celluloseExamples: starch, glycogen, cellulose Consist of many monomers bonded Consist of many monomers bonded

togethertogether Used for energy storage and to build Used for energy storage and to build

cell structurescell structures Broken down through cellular Broken down through cellular

respiration to create energy (ATP)respiration to create energy (ATP) Test for complex sugars: use Test for complex sugars: use iodineiodine: :

turns from brown to black in the turns from brown to black in the presence of starchpresence of starch

CarbohydratesCarbohydrates

Stimulate the immune systemStimulate the immune system Play a role in binding viruses and Play a role in binding viruses and

bacterial pathogensbacterial pathogens Provide cell structureProvide cell structure

ProteinsProteins

Serve as Serve as structural materialsstructural materials, , energy sources or hormonesenergy sources or hormones

Combined with carbohydrates and Combined with carbohydrates and function on cell surface as function on cell surface as receptorsreceptors

Contain Contain Carbon, hydrogen, oxygenCarbon, hydrogen, oxygen and and nitrogennitrogen. Sometimes they also . Sometimes they also contain contain sulfursulfur atoms atoms

Building blocks are amino acidsBuilding blocks are amino acids

ProteinsProteins

Serve as Serve as Transport moleculesTransport molecules such as hemoglobin carrying such as hemoglobin carrying oxygen in rbc.oxygen in rbc.

Stimulate nerve impulsesStimulate nerve impulses

Provide immune protectionProvide immune protection

Protein CategoriesProtein Categories

Build Cell StructureBuild Cell Structure Transport molecules between cellsTransport molecules between cells Relay messages – hormonesRelay messages – hormones Speed up reactions – enzymesSpeed up reactions – enzymes Test for proteins: use Test for proteins: use biuret’s biuret’s

reagentreagent, turns from blue to violet , turns from blue to violet in the presence of proteinsin the presence of proteins

LipidsLipids

Organic substances which are Organic substances which are insoluble in insoluble in waterwater

Soluble in certain organic solvents such as Soluble in certain organic solvents such as ether or acetoneether or acetone

Include fats, phospholipids and steroidsInclude fats, phospholipids and steroids Store energy for cells and can store more Store energy for cells and can store more

energy, gram for gram, than carbsenergy, gram for gram, than carbs Building blocks for fats are fatty acids and Building blocks for fats are fatty acids and

glycerol.glycerol. 1 glycerol + 3 fatty acids = 1 triglyceride 1 glycerol + 3 fatty acids = 1 triglyceride

moleculemolecule

LipidsLipids

Test for lipids: use Test for lipids: use Sudan IVSudan IV a red a red dye that becomes soluble in the dye that becomes soluble in the presence of lipidspresence of lipids

Lipids are highly useful storage Lipids are highly useful storage molecules, can be broken down to molecules, can be broken down to release more energy than a sugar release more energy than a sugar moleculemolecule

Nucleic AcidsNucleic Acids

Contain carbon, hydrogen, oxygen, Contain carbon, hydrogen, oxygen, nitrogen and phosphorus.nitrogen and phosphorus.

Building blocks are nucleotidesBuilding blocks are nucleotides 2 types of nucleic acids:2 types of nucleic acids:

– RNA: contain riboseRNA: contain ribose– DNA: DeoxyriboseDNA: Deoxyribose

Store and transfer genetic Store and transfer genetic informationinformation

Control cellular activitiesControl cellular activities

Nucleic AcidsNucleic Acids

Provide instruction for making Provide instruction for making proteins which direct the proteins which direct the structure and activity of the cellstructure and activity of the cell– Ex. RNA, DNA, NADEx. RNA, DNA, NAD– DNA is the most important of these DNA is the most important of these

molecules because it makes the molecules because it makes the organism what it isorganism what it is

4 Classes of Biological 4 Classes of Biological moleculesmolecules

Biological molecule

Repeating subunit

Proteins Amino acids

Carbohydrates Simple sugars

Nucleic Acid Nucleotides

Lipids No single repeating unit exists. Primarily hydrocarbons, which are chains of carbon molecules linked to hydrogens