Clase 2 Chemistry of Cell .ppt

8/13/2019 Clase 2 Chemistry of Cell .ppt

1/73

Basic Chemistry

MatterElements.

AtomsCompounds

Molecules


2/73

A. Matter

Material that takes up space.1. Elements

Pure chemical substances composed of atoms.

Examples?

How many elements exist?

How many of these elements are essential to life?


3/73

Periodic Table of Elements


4/73

2. AtomThe smallest piece of an element that retains the

characteristics of that element.

Composed of 3 subatomic particles:

Protons

Neutrons

Electrons


5/73

Characteristics of Subatomic Particles


6/73

Model of an Atom


7/73


8/73

Atomic symbol

Atomic number

Atomic mass (weight).

ATOMS


9/73

CHEMICAL REACTIONS

Electron shells

Valence (outer)

shellOctet rule

Ionic bonds

Covalent bonds


10/73

Atoms will strive to fill their

outer (valence) orbitals

If an atom has 1 valence e-,

its happy to give it awayExample: Sodium

1 valence e-


11/73

Atoms will strive to fill their

outer (valence) orbitals

ANDIf an atom has 7

valence e-, its happy to

pick up one

Ex. Chlorine

7 valence e-


12/73

Ionic Bonds


13/73


14/73

Ions can have important biological

functions.


15/73

Covalent Bonding

Carbon (C)4

CC H

Hydrogen (H)1

CCH

H

H

H

Methane CH4

Each pair of electrons

represents the formation

of a covalent bond.


16/73

Aside from single covalent bonds, double,

or triple covalent bonds can form.


17/73


18/73

Review

Ionic bonds occur when e- are shared in a+/- arrangement

Covalent bonds exist when one atom shares1 or more e- with another atom.

One covalent bond means 2 e- are involved.Always involves a pair of e-


19/73

Oxidation/Reduction

Oxidation----loss of electron

Reduction----Gain of electron

Examples?


20/73

Water is the most abundant molecule inliving things.

Water has special traits that make itimportant to life.

Water and Life


21/73

Water molecules: 2-H covalently bonded

to 1-O. Covalent=shared e-

. But issharing equal?


22/73

Chemistry of Water

Amazing stuff!!!

Should not be a liquidat room temp

Highly Polar

molecule.


23/73

WATER

Hydrogen bonds

Polarity


24/73

Hydrogen Bonding

Positively charged hydrogen end

Negatively charged oxygen end Hydrogen Bonds

Covalent bonds between hydrogen and oxygen


25/73

Characteristics of water:

1. liquid at room temperature2. universal solvent for polar molecules

3. water molecules are cohesive

4. water molecules are adhesive5. temperature of water changes slowly

6. absorbs heat upon vaporization

7. releases heat upon freezing

8. frozen water is less dense


26/73

B. The Importance of Water

1. Properties

Cohesion- the attraction of water moleculesfor each other.

Adhesion- the attraction of water moleculesfor other compounds.

High heat capacitytakes a great deal ofheat to raise the temperature of water.


27/73

High heat of vaporization- a lot of heat isrequired to evaporate water.

Exists as solid, liquid or gas - solid (ice) is lessdense than liquid.

2. Solutions

A solution is a mixture of one or more solutesdissolvedin a solvent.

If solvent is water, then it is an aqueous solution.

Water is a strong solvent because it separates charged

atoms or molecules.


28/73

Water as a

SolventHow itWorks


29/73

Dissociation of Water Molecules

Water dissociates and releases hydrogen ions(H+) and hydroxide ions (OH-).


30/73

ACIDS AND BASESAcids- release hydrogen ions(H+) in solution.HCl H+ + Cl-

Bases- take up hydrogen ions(H+) or give off hydroxide ions

(OH-) in solution.NaOH Na+ + OH-


31/73

pHa Measure of Acidity

If ph7, base

7=neutral


32/73

Buffers --substances thathelp to resist change in pH.

Why important?


33/73

WaterFinal Notes

Hydrophilic--polar

Hydrophobicnon-polar

Amphipathic---containhydrophilic and hydrophobicparts


34/73

Organic molecules are found in livingthings.

The chemistry of carbon accounts forthe chemistry of organic molecules.

Macromolecules (Polymers)

Organic Moleculescarbon based


35/73

Organic Molecules

organic monomer

polymer

M l l ( l )


36/73

Macromolecules (polymers)and monomers.

Polymer Monomer

carbohydrate monosaccharidesprotein amino acid

nucleic acid nucleotide

D h d i S h i


37/73

Dehydration Synthesis orCondensation Reactions

vsHydrolysis

A BOH H+ + HOH

or

H2O

A B

covalent bonds

If the reaction is carried out multiple times you create a polymer!

+ H2O molecules

Condensation

Hydrolysis

Dehydration (condensation) builds. Hydrolysis breaks down.


38/73

What do they do?

Structure

Act as enzymesto speed reactionsServe as carriers

Act as antibodies

Transporters and channels

Proteins


39/73

Proteins --polymers of amino acids.


40/73

Peptide Bonds

Proteins--Levels of Organization


41/73

Proteins--Levels of Organization.

TERTIARY (3) STRUCTURE 3D


42/73

TERTIARY (3) STRUCTURE3D 1 structure and

environment

FactorsR-groups

Hydrogen bonding

Hydrophobic interactions

Ionic (salt) bridges

Disulfide bonds

Native vs Denatured

REMEMBER: APROTEINS FUNCTIONIS A RESULT OF ITSFORM!!


43/73

Catalyst?

Speeds up reaction

ProteinsThe Model:

EnzymesBiological Catalysts

E+S ES E+P

E=Enzyme

S=Substrate

P=Product

Enzymes Lower Energy of


44/73

Enzymes Lower Energy ofActivation

Enzymes-- lower the energy barrier


45/73

EA

barrier

Reactants

1 Products 2

En

zyme

Figure 5.5A

Enzymes lower the energy barrier


46/73

Enzyme-Substrate Complexes

Every reaction in a cell requires a specificenzyme.

Enzymes are named for their substrates:

Substrate EnzymeLipid Lipase

Urea Urease

Maltose MaltaseRibonucleic acid Ribonuclease


47/73

Cell Chemistry

Enzymesinvolved in almost allchemical reactions.

AnabolismThe building

reactions. EX. Protein synthesis

CatabolismThe breakdown

reactions. EX. Protein digestionMetabolismsum of all reactions

E C f t


48/73

Enzyme Cofactors

Cofactors---may be necessary forsome enzymes to carry out theirfunctions. Two types:

Metal ions. EX copper (Cu+2) or iron(Fe+2)

CoenzymesOrganic molecules,must be present for other enzymesto function. EX vitamins

L l f P t i St t


49/73

Levels of Protein StructureQuaternary (4) Structure

Multiple chains:interactions of morethan one polypeptide

chain to form thecomplete, functionalprotein. Ex.Hemoglobin andantibodies


50/73

Generally, C:H:O in a 1:2:1 ratio(CH2O)n

Functions

quick energy and short-term energystorage. EX glycogen, starch

Structure. EX. Cellulose

Polymer=polysaccharides EX. Starch Monomers= monosaccharides EX.

glucose

Carbohydrates


51/73

NOMENCLATURE

Based on number of carbons

3C==triose

4C==tetrose

5C==pentose, etc


52/73

Structure of Glucose


53/73

Disaccharides


54/73

Polymerization of Carbohydrates

O S CC S


55/73

POLYSACCHARIDES

STARCH

GLYCOGEN

CELLULOSE

LIPIDS


56/73

LIPIDS

NON-POLAR BIOLOGICAL MOLECULESFUNCTIONS

Energy storage: Fats and oils.

Waterproofing: Waxes and oils Insulation: Fat layers (blubber)

Cushioning: Fat layers (soles of your feet)

Regulating metabolism: Steroids

Component of cell membranes: Phospholipids


57/73

Lipid structure (Triglyceride)

Glycerol backbone

Fatty acid tails

Fats vs oils X3


58/73

Triglyceride formation

H

H-COH

H-COH

H-COH

H

GLYCEROL

O H H H H H

HO-C-C-C-C-C-C-H

H H H H H

O H H H H H

HO-C-C-C-C-C-C-H

H H H H H

O H H H H H

HO-C-C-C-C-C-C-HH H H H H

FATTY ACIDS

H

H-CO

H-CO

H-CO

H

O H H H H H

-C-C-C-C-C-C-H

H H H H HO H H H H H

-C-C-C-C-C-C-H

H H H H H

O H H H H H

-C-C-C-C-C-C-H

H H H H H

+ H2

0

+ 3 H20TRIGLYCERIDE

What type of reaction forms a triglyceride? Dehydration Synthesis

+ H20

+ H20


59/73

Saturated vs. Unsaturated Fats

Saturated vs Unsaturated Fats


60/73

Saturated vs. Unsaturated Fats

F tt A id i t


61/73

Fatty Acids: cis vs. trans

-linolenicacid

Trans -linolenic acid

Ph h li id


62/73

Phospholipids

The majorstructuralcomponent

of cellmembranes

Ph h li id B h i


63/73

Phospholipid Behavior

Phospholipids


64/73

Phospholipids

S d E l ifi


65/73

Soaps and Emulsifiers

Steroids-Hormones and


66/73

Steroids Hormones andStructure


67/73

N l tid St t


68/73

Nucleotide Structure

DNA RNA


69/73

DNA vs RNA

The Double Helix of DNA-


70/73

e oub e e oComplementary base pairing

The Central Dogma ATGAGTAACGCGTACTCATTGCGCDNA-gene


71/73

Transcription---

Translation---

Replication---

RNA

Protein

DNA

duplication of DNA using DNA as the template

synthesis of RNA using DNA as the template

synthesis of proteins using RNA as the template

TACTCATTGCGC

ATGAGTAACGCGTACTCATTGCGC

ATGAGTAACGCG

TACTCATTGCGC

+

AUGAGUAACGCG

MetSerAsnAla

mRNA-message

Protein--end product

DNA gene

M t ti DNA Ch


72/73

Mutation-DNA Change

d h h


73/73

Adenosine Triphosphate-ATP

Adenosine triphosphate(ATP) is

the energy currency of cells

Clase 2 Chemistry of Cell .ppt

Documents