Introduction to Introduction to BioChemistry: BioChemistry: Cellular FunctionsCellular Functions

Did you know???...Did you know???... Most organisms are made up Most organisms are made up

of only 6 common elements?of only 6 common elements? Within cells these few Within cells these few

molecules are combined in molecules are combined in many different ways to carry many different ways to carry out a variety of functions that out a variety of functions that are the key to life.are the key to life.

The invention of the electron The invention of the electron microscope allowed scientists microscope allowed scientists to study the internal structures to study the internal structures of the cell which led to the cell of the cell which led to the cell theory:theory:

1.1. All living things are composed of All living things are composed of cells.cells.

2.2. Cells are the smallest functional Cells are the smallest functional unit of life.unit of life.

3.3. All cells come from pre-existing All cells come from pre-existing cells.cells.

– The cell can also be explored The cell can also be explored through chemical knowledge through chemical knowledge and procedures.and procedures.

BiochemistryBiochemistry The study of the chemistry of living things, The study of the chemistry of living things,

including the chemical substances and including the chemical substances and processes involved.processes involved.

Molecular Basis of LifeMolecular Basis of Life

The molecules of life that nourish, build and The molecules of life that nourish, build and direct cell activity include:direct cell activity include:

1.1. WaterWater2.2. Organic CompoundsOrganic Compounds3.3. Macromolecules:Macromolecules:

CarbohydratesCarbohydratesProteinsProteinsLipidsLipidsNucleic AcidsNucleic Acids

Living Organisms Need:Living Organisms Need: HH22O, OO, O22 and CO and CO22

Cellular RespirationCellular Respiration is the process by is the process by which cells release energy from oxygen which cells release energy from oxygen and simple food molecules.and simple food molecules.

What is the equation for cellular What is the equation for cellular respiration?...respiration?...

Cellular RespirationCellular Respiration

CC66HH1212OO66 + 6O + 6O22 6CO 6CO22 + Energy +6H + Energy +6H22OO

Glucose + oxygen Glucose + oxygen carbon dioxide + carbon dioxide + energy + waterenergy + water

Water: The Primary Water: The Primary Molecule of LifeMolecule of Life

The most abundant molecule in any cellThe most abundant molecule in any cell Transports materials in/out of the cell.Transports materials in/out of the cell. Raw material for essential cell reactions.Raw material for essential cell reactions. Lubricant between organs, tissues and Lubricant between organs, tissues and

individual cells.individual cells. Remains liquid over a wide temperature range Remains liquid over a wide temperature range

and changes temperature gradually allowing and changes temperature gradually allowing for a stable environment.for a stable environment.

Expands when it becomes a solid.Expands when it becomes a solid.

Water moleculesWater molecules

These important properties of water are These important properties of water are determined by its chemical structure.determined by its chemical structure.

Water molecules have an uneven charge Water molecules have an uneven charge distribution and are polar.distribution and are polar.

Properties of Water

Organic CompoundsOrganic Compounds Refer to molecules that contain Refer to molecules that contain

both carbon and hydrogen. both carbon and hydrogen. May also contain O, N, P, SMay also contain O, N, P, S

HydrocarbonsHydrocarbons refer to refer to molecules containing only molecules containing only carbon and hydrogen.carbon and hydrogen.

Covalent bonds (share Covalent bonds (share electrons)electrons)

Include macromolecules such Include macromolecules such as carbohydrates, lipids, as carbohydrates, lipids, proteins and nucleic acid.proteins and nucleic acid.

PolysaccharidesPolysaccharides A few hundred to a few thousand A few hundred to a few thousand

monosaccharides joined together.monosaccharides joined together. Storage polysaccharides – Starch, Storage polysaccharides – Starch,

GlycogenGlycogen Structural polysaccharides – CelluloseStructural polysaccharides – Cellulose

Starch Starch StorageStorage Starch is the storage for Starch is the storage for

energy in plants.energy in plants. Glycogen performs the Glycogen performs the

same function in animals.same function in animals. Glycogen molecules hold Glycogen molecules hold

more glucose units than more glucose units than starch due to their starch due to their branching structure.branching structure.

Examples include: Grains, Examples include: Grains, Potatoes, RicePotatoes, Rice

StarchStarch Composed entirely of Composed entirely of

alpha glucose alpha glucose monomersmonomers

Two forms: amylose Two forms: amylose (unbranched) and (unbranched) and amylopectin (branched)amylopectin (branched)

In plants, sugar is stored In plants, sugar is stored as starch. The sugar as starch. The sugar can be held until need at can be held until need at which time, it can be which time, it can be withdrawn through withdrawn through hydrolysis.hydrolysis.

AmyloseAmylose

AmylopectinAmylopectin

Amylopectin forms branched structures Amylopectin forms branched structures with about 30 glucose units in a chain with about 30 glucose units in a chain between branches. between branches.

CarbohydrateCarbohydratess

Carbon + waterCarbon + water Provides short or long term Provides short or long term

energy storageenergy storage Monosaccharides (simple Monosaccharides (simple

sugar)sugar) Made of carbon chains that are Made of carbon chains that are

3-7 carbons long3-7 carbons long Glucose is the most common and Glucose is the most common and

is a 6 carbon sugar (hexoses) is a 6 carbon sugar (hexoses) with the formula Cwith the formula C66HH1212OO66

Trioses (3 carbon sugars) & Trioses (3 carbon sugars) & pentoses (5 carbon sugars) are pentoses (5 carbon sugars) are also common.also common.

Main fuel for cellular workMain fuel for cellular work When not used immediately, they When not used immediately, they

are generally stored as are generally stored as disaccharides and disaccharides and polysaccharides.polysaccharides.

MonosaccharidesMonosaccharides

Different formations of Different formations of glucoseglucose

DisaccharidesDisaccharides

2 monosaccharides joined through 2 monosaccharides joined through dehydration synthesis (water is removed)dehydration synthesis (water is removed)

Glucose + Glucose = Maltose (brewing of Glucose + Glucose = Maltose (brewing of beer)beer)

Glucose + Galactose = Lactose (milk)Glucose + Galactose = Lactose (milk) Glucose + Fructose = Sucrose (table Glucose + Fructose = Sucrose (table

sugar)sugar)

Dehydration SynthesisDehydration Synthesis

Cellulose Cellulose Structure Structure Cellulose is produced by plants and used as Cellulose is produced by plants and used as

part of the cell wall.part of the cell wall. It protects cells and provides support for the It protects cells and provides support for the

plantplant

CelluloseCellulose Composed entirely of beta glucose Composed entirely of beta glucose

monomers.monomers. Parallel cellulose molecules intertwine to Parallel cellulose molecules intertwine to

form strong cable structures.form strong cable structures. Fresh fruit, vegetables and grains are rich Fresh fruit, vegetables and grains are rich

in cellulose or fiber.in cellulose or fiber.

CelluloseCellulose It also contains a large amount of energy It also contains a large amount of energy

that is not available to humans. Only a that is not available to humans. Only a few bacterial species contain the few bacterial species contain the necessary enzymes to break down necessary enzymes to break down cellulose, these bacteria live in the guts of cellulose, these bacteria live in the guts of cattle, rabbits and even termites. However cattle, rabbits and even termites. However they are not found in humans. That’s why they are not found in humans. That’s why we cannot break down food such as we cannot break down food such as celery!celery!