biochem ppt

Biochemistry Notes

Unit 1

Chapter 6

Elements

Chemistry in Biology

An element is a pure substance that cannot be broken down

Each element has a unique name and symbol.

6.1 Atoms, Elements, and Compounds

Chapter 6

The Periodic Table of Elements


Horizontal rows are called periods. Vertical columns are called groups.


Chapter 6

Chemistry = study of matter.


Atoms are the building blocks of matter.

Chapter 6 Chemistry in Biology

Neutrons and protons are located at the nucleus of the atom.

Protons are positively charged particles.

Neutrons are particles that have no charge.

Electrons are negatively charged particles that are located outside the nucleus.



Chapter 6

• Atomic Number: number of protons in the nucleus of an element (atom).


• Atomic Mass: the number of protons & neutrons in the nucleus of an element (atom).

• Find the neutrons only:• Atomic mass-atomic number=neutrons• Ex: Carbon Picture


Isotopes


Atoms of the same element that have the same number of protons and electrons but have a different number of neutrons


Chapter 6

Compounds


A pure substance formed when two or more different elements combine

Compounds cannot be broken down into simpler compounds or elements by physical means, must be a chemical reaction


Chapter 6

Chemical Bonds


Covalent bonds

Chemical bond that forms when electrons are shared A molecule is acompound in which the atoms are held together by covalent bonds.


Chapter 6

Ionic Bonds


Electrical attraction between two oppositely charged atoms or groups of atoms


Chapter 6

Water’s Polarity

6.3 Water and Solutions


Molecules that have an unequal distribution of charges are called polar molecules.

Polarity is the property of having two opposite poles. (Think of North & South Pole)

A hydrogen bond is a bond involving a hydrogen atom and a fluorine, oxygen, or nitrogen atom.

Chapter 6



Chapter 6


van der Waals Forces

When molecules come close together, the attractive forces between slightly positive and negative regions pull on the molecules and hold them together.

The strength of the attraction depends on the size of the molecule, its shape, and its ability to attract electrons.


Chapter 6

Water properties:

Water is cohesive

Cohesion: sticks to itself

Ex: allows some insects & spiders can “walk” on the surface

Water is adhesive

Adhesion: sticks to other things

Ex: capillary action-pulls column of water up to the top of a plant

Water properties: Water is called “Universal solvent”: dissolves many other substances due to polarity

Differences in charges pulls/pushes substances apart (Like a magnet attracts or repels other magnets)

Water exhibits evaporative cooling: removes heat when it evaporates from a surface

Ex: sweating cools skin

Water expands during freezing: expands into crystal formation releasing heat

Ex: ice floating on water


Heterogeneous Mixtures

In a heterogeneous mixture, the components remain distinct.

A salad is a heterogeneous mixture.


Chapter 6


Homogenous Mixtures

A mixture that has a uniform composition throughout

A solvent is a substance in which another substance is dissolved.

A solute is the substance that is dissolved in the solvent.

Food coloring dissolved in water forms a homogenous mixture.


Chapter 6


Excess of hydrogen ions (H+) are called acids.

Excess of hydroxide ions (OH–) are called bases.

Acids and Bases


Chapter 6


The measure of concentration of H+ in a solution is called pH.

Acidic solutions have pH values 0-6.99. Basic solutions have pH values 7.01-14

pH and Buffers6.3 Water and Solutions

Chapter 6

Basic solutions have pH values 7.01-14 Neutral solutions have a pH value 7.00


Buffers are mixtures that can react with acids or bases to keep the pH within a particular range.


Chapter 6

Organic Chemistry

The study of all compounds containing the element CARBON

6.4 The Building Blocks of Life

Chemistry in BiologyChapter 6


Carbon compounds can be in the shape of straight chains, branched chains, & rings.


Chapter 6

What is a macromolecule?

A giant molecule made up of 100’s or 1000’s or smaller units called MONOMERS

Macromolecules are also called polymers!!!!

The 4 types of macromolecules:

CARBOHYDRATES

LIPIDS

NUCLEIC ACIDS

PROTEINS


Carbohydrates

Made up of carbon, hydrogen, and oxygen


Chapter 6

CARBOHYDRATES Used as main source of energy

Building block: glucose (C6H12O6)

Two types:

Sugars: quick source of energy

Monosaccharide-simple sugar, disaccharide-2, polysaccharide-many

Ex: glucose, lactose, fructose, sucrose

Starches: source of energy breaking down slower

Ex: potatoes, pasta, bread, grains

Section 2-3

Figure 2-13 A Starch

Go to Section:

Where found?• Cellulose: plant cell walls

• Glycogen: animal liver

http://www.topnews.in/health/files/Liver-Damage.jpg

Nucleic Acids Made up of H,O,N,C & P

Store and transmit genetic info in nucleus

Made up of nucleotides

Two types (examples): DNA & RNA

PROTEINS Made up of N,C,H, O

Made up of groups called amino acids (20 in nature)

proteins have a large variety of sizes & shapes

If the shape changes, it becomes a new protein

Examples: muscles, peanuts, soybeans



Chapter 6

LIPIDS Made up mainly of C & H

Used to store energy, insulation & protection

Usually not soluble in water

Made up of long chains of fatty acids

Contrasting Lipids

Lipids/Triglyceride

Fats (Mostly solid at room temperature)

Saturated(Solid at room temp &

“saturated” with Hydrogen atoms, single bonds)

Unsaturated(Liquid at room temp & have double bonds.few Hydrogen atoms)

Oils(Liquid at room temperature &

Considered mostly unsaturatedfats)

Saturated Fats Ex’s:

Unsaturated fats Ex’s:

• Some cooking oils

• Nuts• Margarine• Fish oils

Reactants and Products

A chemical reaction is the process by which atoms or groups of atoms in substances are reorganized into different substances.

6.2 Chemical Reactions

Clues that a chemical reaction has taken place include the production of heat or light, and formation of a gas, liquid, or solid.


Chemical reaction

Physical reaction

Chapter 6

Chemical Equations


Chemical formulas describe the substances in the reaction and arrows indicate the process of change.

Reactants are the starting substances, on the left side of the arrow.

Products are the substances formed, on the right side of the arrow.


Chapter 6

Dehydration Synthesis

• A chemical reaction that builds molecules by losing water molecules (H2O)

Before After

http://www.youtube.com/watch?v=UyDnnD3fMaU

Hydrolysis• Chemical reaction splitting a compound

into 2 by adding water (H2O)

Before

After


Activation energy: the minimum amount of energy needed for reactants to form products in a chemical reaction.

Energy of Reactions


Chapter 6


This reaction is exothermic and released heat energy.

The energy of the product is lower than the energy of the reactants.

Ex. Na+ + Cl- =NaCl (salt)


Chapter 6


This reaction is endothermic and absorbed heat energy.

The energy of the products is higher than the energy of the reactants.

Ex: photosynthesis


Chapter 6


A catalyst is a substance that lowers the activation energy and speeds up a reaction

Enzymes are biological catalysts.

It does not increase howmuch product is made and it can be re-used

over and over again.

Enzymes


Chapter 6


The reactants that bind to the enzyme are called substrates.

The specific location where a substrate binds on an enzyme is called the active site.


Chapter 6

Fits together like a lock and key


Factors such as pH, temperature, and enzyme concentration


Chapter 6

The active site specifically is shaped to match the substrate and forms the enzyme-substrate complex, which helps bonds in the reactants to be broken and new bonds to form.

biochem ppt

Documents

groups of atoms

column of water

magnets water

number of protons neutrons

element atom

atomic massatomic number

plant water properties

different number of