Unit 4: CellsUnit 4: Cells Biological Molecules & WaterBiological Molecules & Water

The Major Chemical Elements The Major Chemical Elements in Cellsin Cells

Carbon Carbon C C Atomic # 6Atomic # 6 Hydrogen Hydrogen HH Atomic # 1Atomic # 1 Nitrogen Nitrogen NN Atomic # 7Atomic # 7 Oxygen Oxygen OO Atomic # 8Atomic # 8 PhosphorusPhosphorus PP Atomic # 15Atomic # 15 Sulfur Sulfur SS Atomic # 16Atomic # 16

WaterWater The single most abundant The single most abundant

compound found in living things.compound found in living things. One of the few compounds that One of the few compounds that

are liquid at the temperature are liquid at the temperature found over much of the Earth’s found over much of the Earth’s surface.surface.

Expands as it freezes. Ice is less Expands as it freezes. Ice is less dense than water.dense than water.

Oven cleaner

Bleach

Ammonia solution

Soap

Sea water

Human bloodPure waterMilkNormalrainfall

Acid rainTomatojuice

Lemon juice

Stomach acid

Neutral

Incr

easi

ngly

Bas

icIn

crea

sing

ly A

cidi

c

Section 2-2

pH Scale

•Pure water has a pH of 7. • This means it is neutral.

Section 2-2Figure 2-9 NaCI Solution

Cl-

Water

Cl-Na+

Water

Na+

Water is a universal solvent.

WaterWater

HH22OO It is a neutral molecule (10 protons It is a neutral molecule (10 protons

and 10 electrons).and 10 electrons).

A water molecule is polar.A water molecule is polar.• there is an uneven distribution of there is an uneven distribution of

electrons between the oxygen and the electrons between the oxygen and the hydrogen atomshydrogen atoms. .

Water is cohesive.Water is cohesive. CohesionCohesion is an attraction is an attraction

between molecules of the same between molecules of the same substance.substance.

Water is AdhesiveWater is Adhesive AdhesionAdhesion is an attraction between is an attraction between

molecules of different substances.molecules of different substances.

Organic Macromolecules http://teachertube.com/viewVideo.php?video_id=43698

Formed by a process known as polymerization. Large compounds are built by joining

smaller ones together. Monomers = smaller units Polymers = joined together

monomers.

CarbohydratesCarbohydrateshttp://streaming.teachertube.com/viewVideo.php?title=Carbohydrates&video_id=43700 http://streaming.teachertube.com/viewVideo.php?title=Carbohydrates&video_id=43700

Living things use carbohydrates as Living things use carbohydrates as their main source of energy.their main source of energy. Made of carbon, hydrogen, and oxygen usually in a 1:2:1 Made of carbon, hydrogen, and oxygen usually in a 1:2:1

ratio.ratio. MonosaccharideMonosaccharide

• A single sugar molecule.A single sugar molecule. Glucose, galactose, and fructose.Glucose, galactose, and fructose.

PolysaccharidesPolysaccharides• Large macromolecules formed from Large macromolecules formed from

monosaccharides.monosaccharides. Many animals store glycogen.Many animals store glycogen.

• Plant use plant starch and cellulose.Plant use plant starch and cellulose.

Starch

Glucose

Section 2-3

Figure 2-13 A Starch

LipidsLipidshttp://www.teachertube.com/viewVideo.php?video_id=43703 http://www.teachertube.com/viewVideo.php?video_id=43703

Lipids can be used Lipids can be used to store energy. to store energy. important part of important part of

membranes and waterproof membranes and waterproof coverings.coverings.

• Generally not soluble in water.Generally not soluble in water.

Made mostly from carbon and Made mostly from carbon and

hydrogenhydrogen.. Common categories are Common categories are

fats, oils, and waxes.fats, oils, and waxes.

LipidsLipids

SaturatedSaturated – the fatty – the fatty acids contain the acids contain the maximum possible maximum possible number of hydrogen number of hydrogen atoms.atoms.

UnsaturatedUnsaturated – The – The fatty acid contains at fatty acid contains at least one carbon to least one carbon to carbon double bond.carbon double bond.

PolyunsaturatedPolyunsaturated means that it contains means that it contains more than one double more than one double bond.bond.

Nucleic AcidsNucleic Acids http://www.teachertube.com/viewVideo.php?http://www.teachertube.com/viewVideo.php?

video_id=43705&title=Nucliec_Acids video_id=43705&title=Nucliec_Acids

Nucleic acids store Nucleic acids store and transmit and transmit heredity, or genetic heredity, or genetic informationinformation.. Contain hydrogen, Contain hydrogen,

oxygen, nitrogen, oxygen, nitrogen, carbon, and carbon, and phosphorus.phosphorus.

Polymers assembled Polymers assembled from nucleotidesfrom nucleotides..

Nucleotides consist of three Nucleotides consist of three parts: a 5-carbon sugar, a parts: a 5-carbon sugar, a phosphate group, and a phosphate group, and a nitrogenous basenitrogenous base

There are two types There are two types of nucleic acids.of nucleic acids.

• Ribonucleic Acid (RNA)Ribonucleic Acid (RNA)• Deoxyribonucleic Acid Deoxyribonucleic Acid

(DNA)(DNA)

ProteinsProteinshttp://www.teachertube.com/viewVideo.php?video_id=43704http://www.teachertube.com/viewVideo.php?video_id=43704

Protein FunctionsProtein Functions:: control the rate of reactionscontrol the rate of reactions regulate cell processes. regulate cell processes. form bones and muscles.form bones and muscles. transport substances into or transport substances into or

out of the cell.out of the cell. fight disease.fight disease.

General structureAlanine Serine

Section 2-3

Contain nitrogen, carbon, hydrogen, and oxygen.

Polymers of amino acids.

igure 2-16 Amino Acids

Amino group

Carboxyl group

Proteins

Aminoacids

Section 2-3

Figure 2-17 A Protein

Proteins have 4 levels of Proteins have 4 levels of OrganizationOrganization

1st level 1st level is the sequence of amino acids in the is the sequence of amino acids in the protein chain,protein chain,

2nd level 2nd level is the amino acids can be twisted within is the amino acids can be twisted within the chain.the chain.

3rd level 3rd level is the chain is the chain

itself may be folded.itself may be folded. 4th level 4th level is if a protein has is if a protein has

more than one chain, eachmore than one chain, each chain has a specific chain has a specific arrangement.arrangement.