2- Chemistry of Life I

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Announcements 8/29

• Lab starts this week!– Proper Dress required– There are no assignments due this week at the

beginning of lab• Good idea to look over Ex. 1 and 2

• No labs Labor Day week due to short week (that is next week)

• All connect assignments are up for Module 1• Tegrity- explanation

The Chemistry of Life I

Chapter 2

Outline for Today

I. Matter and the Elements

II. Inorganic MatterA. Water

B. Minerals

C. Gases

III. Organic CompoundsA. Overview

B. Classes of Biomolecules1. Carbohydrates

2. Continued in The Chemistry of Life_2

I. Matter and the Elements

http://www.microwaves101.com/encyclopedia/periodicchart.cfm

CpRgDs

• Hopefully, you remember much of your basic chemistry from last year

• Electrons important in bonding– Covalent vs. ionic bonding– Hydrogen bonding (discuss shortly)

COMPOSITION OF LIVING MATTER

I. The Elements

electrolytes

Co-factors forEssential proteins

Essential elementof thyroid hormone

II. Inorganic Matter: Water

COMPOSITION OF LIVING MATTER

II. Inorganic Compounds

1. WATER

a. Properties that make it the IDEAL solvent for the human body

i. Solvency

ii. Polarity

iii. Adhesion/cohesion

iv. Neutral pH

v. Thermal properties

vi. Reactivity

Fig. 2.8

Solvency/Polarity

Fig. 2.9

δ means a small chargePolar – slightly charged at opposite ends

http://library.thinkquest.org/10429/low/matter/matter.htm

δ+δ+

http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookCHEM2.html

Solvency/Polarity

• Adhesion means to stick to other things while cohesion means to stick to itself

• Hydrogen bonds cause cohesiveness– Get a surface tension

• Forms a lubrication– What does this do?

• Cuts down on friction

Adhesion/Cohesion

Fig. 2.8

Notice the positive and negative interactions

H bonds are due to H bonding with F, O, or N (F not seen in biological systems)

• Acids or bases affect protein structure– Can render the protein non-functional

Neutral pH

Fig. 2.12

• High Heat Capacity– Amount of energy it

takes to raise 1g of water 1 oC.

– Takes a lot of energy to change the temperature of water

– Stabilization of body temperature

Thermal Stability

• High heat of vaporization– Liquid gas– Heat goes with it– Cools the body

– 1 ml of perspiration evaporating from the body removes 500 cals of heat

Thermal Stability

SWEATING is our main mechanism of heat release

Reactivity

• water is essential in many chemical reactions

universal solvent• water is added to break

covalent bonds

• is crucial in metabolism

• (will discuss more in organic cmpds)

Fig. 2.15

Anabolic reaction

Catabolic reaction

II. Inorganic Matter: Minerals

II. Inorganic Compounds

2. MINERALS

a. elements extracted from the soil; consumed in our diet

b. main minerals are calcium, phosphorus, potassium, sodium, chloride, magnesium, zinc, copper

c. are crucial for synthesis and maintenance of:

Muscles

Neurons

Calcium, phosphorus

Calcium, sodium, phosphorus

Calcium, sodium, potassium,phosphorus

II. Inorganic Matter: Gases

Gases: Important ones

• Oxygen (O2)– Cellular respiration

• Carbon Dioxide (CO2)– Waste product

• Nitrous Oxide– neurotransmitter

• Methane (CH4)

• Carbon monoxide (CO) is a problem

III. Organic Compounds

Fig. 2.14

• Valence of 4– Can form maximum of 4

bonds– Single, double, triple bonds

• Gives a lot of variety due to the functional groups– Clusters of atoms that

determine the chemical properties/reactivity

Fig. 2.23a

Overview - Carbon

http://www.elmhurst.edu/~chm/vchembook/202linear.html

Functional Groups in Organic Compounds

Fig. 2.14

• Macromolecules are large molecules– Usually composed of repeating units

• monomers polymers ( a dimer in the above fig.)• Put together via dehydration synthesis (condensation

reaction)• Notice the loss of water from the molecule

Organic Compounds : Synthesis and Degradation Reactions

Fig. 2.15

• Polymer (dimer) smaller units (e.g. monomers)• Larger molecules broken apart via hydrolysis

reaction (“splitting with water”)• Water is used up in the reaction

Fig. 2.15

• Notice that both involve water– Loss from or addition to the molecule(s)

• Both also involve enzymes (get to later with proteins)

Fig. 2.15

You join 11 organic molecules together. How many water molecules are formed?

6. No way to tell

III. Major classes of compounds

http://www.steve.gb.com/images/molecules/cofactors/NADH.jpg

• “Carbon Water” – C, H, and O

• Basic unit is the monosaccharide– Can have

disaccharides and polysaccharides

• Functions are energy and structure

Carbohydrates

• Simple sugars• Most important are 6

carbon hexoses and 5 carbon pentoses– Pentose examples are

ribose and deoxyribose

– Hexose examples are shown on the right

Fig. 2.16

Monosaccharides

Tab 2.6

• Two monosaccharides joined by a dehydration synthesis

• Degraded to monosaccharides for nutritional purposes

Fig. 2.17

Disaccharides

fructoseglucose

glucose

glucose glucose

galactose

Tab 2.6

• What is a polymer?– Link similar small molecules together– Polysaccharides can have a mw of 500,000 or more

while glucose is 180• Glycogen, starch, and cellulose are important

polysaccharides

Fig. 2.18

Polysaccharides

• Glycogen– Energy storing molecule– Only polysaccharide found in human tissues– Made by cells of liver, muscle, uterus, and vagina– Can be broken down to maintain blood glucose – Branching allows for more storage

Fig. 2.18

Polysaccharides

• Starch– Energy storing

molecule in plants– Plants rely on it when

photosynthesis is not occurring

Polysaccharides

• Cellulose– Structural molecule for plant support– Major component of wood– Most common organic compound on earth– Common component of our diets but we have no enzymes to

digest it• Roughage

http://www.steve.gb.com/images/molecules/sugars/cellulose.png

Polysaccharides

Tab 2.6

• Means the carbs are covalently bonded to proteins or lipids

• Glycolipids and glycoproteins – Many of the lipids and

proteins on the cell surface have up to 12 sugars attached

• Proteoglycans– Carb is the major portion

Conjugated Carbohydrates

Notice a pattern?

• Glucose• Fructose• Ribose• Sucrose• Maltose• Cellulose

• If a chemical ends in “ose” it is a carbohydrate

• Note: That does not mean that all carbohydrates end in “ose” (glycogen)

2- Chemistry of Life I

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