Bio Boot Camp

Biochemistry: TOPIC 1

Bio A.2 The Chemical Basis for Life

• Describe how the unique properties of water support life on Earth (freezing point, high specific heat, cohesion)

• Describe and interpret relationships between structure and function at various levels of biochemical organization (atoms, molecules, macromolecules)– Explain how C is uniquely suited to form

biological macromolecules– Describe how macromolecules form from

monomers– Compare the structure and function of

carbs, lipids, proteins and nucleic acids

Bio A.2 The Chemical Basis for Life• Explain how enzymes regulate

biochemical reactions within a cell– Describe the role of an enzyme as a

catalyst in regulating a specific biochemical reaction

– Explain how factors such as pH, temp, and concentration can affect enzyme function

Properties of Water1. Is a polar covalent molecule 2. Is the universal solvent due

to its polarity. Polar covalent compounds (like glucose) and ionic compounds (like salt) can easily go into solution in water.

3. Has a high specific heat. It is slow to heat up and also slow to cool down. This acts as an insulator in living organisms since the majority of their living tissue is water.

4. When water freezes, it expands and therefore floats. Ice is less dense than water. This provides an insulation to the organisms in the water. The water below will be at 4`C (if ice is above it)

Water – Unique Properties

• Adhesion: Water sticks to other substances

• Cohesion: water sticks to water

• Capillary actions: Water climbs up. – Ex. Plant roots to 400 feet

up. • Surface Tension: Water

spiders can walk on water. Water sticks together so tightly, causes a tension so certain things can “float”

Water• The cohesive forces between

liquid molecules are responsible for the phenomenon known as surface tension. The molecules at the surface do not have other like molecules on all sides of them and consequently they cohere more strongly to those directly associated with them on the surface. This forms a surface "film" which makes it more difficult to move an object through the surface than to move it when it is completely submersed.

Facts about water

• Water resists changes to temperature.

• Water expands when it freezes• Water is less dense as a solid oppose

to a liquid. Ice floats• High Specific Heat: able to absorb a

lot of heat before it gets hot• Universal Solvent

Inorganic

• Water is an inorganic molecule: chemical compounds that do not contain carbon as the principle element (exception CO2)

Chemistry of Life• Organic molecules: molecules that

contain carbon atoms and H atoms• C atoms are versatile building blocks

– 4 stable covalent bonds (4 valence e-)– C atoms can bond other C atoms or

other atoms

HHC

H

H

Carbon

• Atomic number of 6. – 2 electrons in the 1st orbital and 4

remaining in the valance orbital.– 4 unpaired will form 4 covalent

bonds

• By bonding with other carbons in chains, rings, single, double and triple bonds, carbon, it can make all sorts of molecules

Covalent bond –electrons are SHARED

Carbon double bond

Carbon (and nitrogen) triple bond

Carbon Chains

Branched chain

Carbon rings

Carbon variety

Monomer and Polymer

Monomers are like legos…

• You can put them together in whatever way you dream up!

Macromolecules• Smaller organic molecules join

together by covalent bonds to form larger molecules– built by linking repeating building blocks

in a chain

• 4 major classes of macromolecules:– carbohydrates– lipids– proteins– nucleic acids

Condensation Reaction (Dehydration Synthesis – removing water to make)

Carbohydrate (CH20)

Monosaccharide, the monomer of a carbohydrate

Carbohydrates• Carbohydrates are composed of C, H,

Ocarbo - hydr - ate

CH2O

(CH2O)x C6H12O6

• Building block molecules or monomers = MONOSACCHARIDES

(glucose)

C6H12O6(CH2O)x

sugar sugar sugar sugar sugar sugar sugarsugar

Carbohydrate Polymers – monomers linked together by

dehydration synthesis

Functions of Carbohydrates • Monosaccharides

– Glucose: quick energy• Polysaccharides

– starch• energy storage in plants

– glycogen• energy storage in animals

– in liver & muscles

– cellulose• structure in plants

– cell walls

Cellulose

Glycogen use and storage

Lipids

Lipids

• Function:– energy storage – cell membrane– insulates body

• think whale blubber!

• Examples– Fats, Oils, Waxes, and

steroids

inside cell

outside cell

Molecular Structure of Fat

not a chain (polymer) = just a “big fat molecule”

Cell membrane phospholipids

Protein

Proteins• Function: worker molecules

– many, many functions•hormones

– signals from one body system to another– insulin

•movement– muscle

•enzymes– help chemical reactions

Proteins

• Building block =

aminoacid

aminoacid–

aminoacid–

aminoacid–

aminoacid–

—N—H

H

H|

—C—|

C—OH

||O

variable group

amino acids

20 different amino acidsPeptide bond

Nucleic Acid

DNADNA

Nucleic Acids• Function:

– genetic material DNA and RNA•stores information

– genes– blueprint for new cells

•transfers information– blueprint for building proteins– DNA RNA protein

proteinsproteins

Nucleic Acids

• Building block =nucleotides

5 different nucleotides different nitrogen bases A, T, C, G, U

nucleotide – nucleotide – nucleotide – nucleotide

phosphate

sugar N base

• This is dehydration synthesis. – Removing water (dehydration)– To make (synthesis)– During this type of reaction, a water molecule is

removed (an –OH from one simple monomer and an –H from another to form a water molecule.

– This joins two monomers together to form a polymer.

Monomer called Glucose

Glucose + Glucose = Maltose

Use the diagram below to answer the question. Chemical Reaction HO – 1 – 2 – 3 – H + HO – 4 - H   HO – 1 – 2 – 3 – 4 – H + H2OThe diagram shows a reaction that forms a polymer from two monomers. What is this type of reaction called?

A.GlycolysisB.HydrolysisC.PhotosynthesisD.Dehydration synthesis

Enzymes• Enzymes are not changed by the

reaction– Enzymes are specific, they fit to their

substrates like a lock and key– used only temporarily then reused– Provide a site for reaction (active site)

enzyme

substrate product

active site

Catalyst/Enzyme• Speeds up chemical reactions by lowering

activation energy

Enzyme

• Fit together like a LOCK AND KEY

Factors that affect enzyme activity pH

Factors that affect enzyme activity Temperature

Factors that affect enzyme activity Concentration

Two molecules join together to make a macromolecule with the removal of water. This type of reaction is called?

A. GlycolysisB. HydrolysisC. PhotosynthesisD. Dehydration synthesis.

A scientist observed that, when the pH of the environment surrounding an enzyme is changed the rate

the enzyme catalyzes a reaction greatly decreases. Which statement best describes how a change in pH can

affect an enzyme?

A. A pH change can cause the enzyme to change its shape

B. A pH change can remove energy necessary to activate an enzyme

C. A pH change can add new molecules to the structures of the enzyme

D. A pH change can cause an enzyme to react with a different substrate.

Substance A is converted to substance B in a metabolic reaction. Which statement best

describes the role of an enzyme during this reaction?

A. It adjusts the pH of the reaction medium

B. It provides energy to carry out the reaction

C. It dissolves substance A in the reaction medium

D. It speeds up the reaction without being consumed.

Carbohydrates and proteins are two types of macromolecules. Which functional

characteristic of proteins distinguished them from carbohydrates?

A. Large amounts of stored informationB. Ability to catalyze biochemical

reactionsC. Efficient storage of usable chemical

energyD. Tendency to make cell membranes

hydrophobic

Practice Questions

Practice Questions

Practice Questions

Practice Questions

Practice Questions

Practice Questions

Practice Questions

Practice Questions