What Makes up Living Things?

• What makes up Water?• What makes up Carbon Dioxide, Oxygen, etc.

Elements

• Substances that are made up of only one type of atom.

• ex. Gold (Symbol: Au) Silver (Ag) Sodium (Na) - are types of metalsOxygen (O), Hydrogen (H), Helium (He), carbon (C) , Chlorine (Cl) Silicon (Si), Sulfur (S)- are types of non-metals

Compounds

• substances made up of two or more elements combined in specific amounts.

• ex: Sodium Chloride-NaCl (formula for table salt)– one atom of sodium for every one atom of

chlorine

• ex: Dihydrogen Oxide-H2O (formula for water)– two hydrogen atoms for every one oxygen atom.

• The cell is a complex "Chemical Factory" made up of the same elements that show up over and over again in different ways.

• Of all the elements found on earth, there are four main elements that are present in the greatest percentages (amounts) in living things. They are

• C- carbon• H- hydrogen• O- oxygen• N- nitrogen

• There are other elements that are also found in living things, but in much smaller quantities. These are:

• S-sulfur, I-Iodine, Na-sodium, Fe-iron, Ca-calcium, K-potassium,

• Cl-chlorine, P-phosphorus Mg-magnesium

• ALL organisms are made up of Inorganic and Organic compounds

I. Inorganic Compounds * compounds that do not contain both carbon and

hydrogen.* organisms do require certain inorganic substances to survive:

A. Water (H2O) * 65% of most living tissues is H2O!!!* many substances in living things are dissolved in water (solution)* water acts as a transport agent to move substances across cell membranes.

B. Salts (ex: NaCl- sodium chloride)* provide many necessary ions for body processes.* help to regulate certain body processes.

C. Acids & Bases* help to regulate certain body processes

Water

• What’s so special about water?

– It’s a great solvent

– It hold’s tons of heat

– It has high surface tension

– Its less dense as a solid than a liquid

pH Matters• pH is a measure of hydrogen ion or H+ conc.• Low pH = Acid (lots of H+s), High pH = Base

(few H+s).

• In biology, keeping H+ levels within a narrow range is critically important

pH Scale

Monomers and Polymers

• Monomers = repeated small units

• Polymers = Long molecules built by linking chain of repeating smaller units

II. Organic Compounds* compounds that contain both carbon

and hydrogen* mainly found in living thingsA. CarbohydratesB. LipidsC. ProteinsD. Nucleic Acids

A. Carbohydrates

* contain C, H, and Oex. glucose-C6H12O6

* most end in -ose* are the main source of energy for respiration* also make up some parts of cells

Structure of a Carbohydrate• * the simplest carbohydrates are called

monosaccharides• (mono=one) (saccharides=sugars)• Each subunit looks like this:

Like a six -sided ring!

Glucose

• What would two rings be called? What about many rings?

• TWO RINGS=a disaccharide (di= two)ex. maltose

• MANY RINGS= a polysaccharide (poly=many)ex. starch, glycogen

Carbohydrates

Carbohydrates

B. Proteins:* contains C, H, O, and N* sometimes contains S* many different jobs:

1. structural parts- proteins make up parts of the cell membrane, as well as body parts like muscles and hair

2. enzymes- a class of proteins that control chemical reaction

3. hormones- chemical messengers that regulate body functions

4. antibodies- protect the body against disease 5. pigments- molecules of color-hemoglobin, melanin,

chlorophyll • You can find proteins in such foods as meats and fish

Proteins• the basic subunit (building block) of a protein is

called an amino acid • each amino acid has 4 parts around a central carbon

atom:

Proteins• A dipeptide is formed when there are 2 amino acids

linked (see picture below). • A polypeptide is formed when 3 or more amino acids

(a.k.a. peptides) are linked together.

C. Lipids:* contains C, H, and O

* no fixed ratio of atomsex: fats and oils* found in cell membrane

* also used for high-energy storage* all lipids have two separate building blocks:

1. 1 glycerol- an alcohol with 3 -OH groups in its molecule

2. 3 fatty acids- a chain of carbon atoms to which hydrogen atoms are bonded; also has a carboxyl group (carboxyl=acids) at one end of the chain.

3 fatty acids and one glycerol make 1 lipid molecule

D. Nucleic Acids:

* contains C, H,O,N, and P (phosphorous) and sometimes (S) sulfur

* carries the genetic code * building blocks are called nucleotides* there are two types of nucleic acidsex. DNA and RNA

Nucleic Acids

DNA-deoxyribonucleic acid * found only in the nucleus

* shape of a double helixRNA-ribonucleic acid (will be taught in detail in

packet #20) * found all over the cell

* 3 types* shape varies according to the type

ENZYMES• used to regulate the rate (speed) of chemical

reactions* all enzymes are proteins

* each chemical reaction in an organism requires its own specific enzyme(each chemical that is worked on by an enzyme is called a substrate)

* each enzyme can also be called an ORGANIC CATALYST

* enzymes are never changed by their reactions!

• Each enzyme has a specific area for linking up with its own specific substrate. This is called an ACTIVE SITE

• THE LOCK AND KEY MODEL 1.) an enzyme and substrate that are compatible

link up at the ACTIVE SITE.2.) This forms the ENZYME-SUBSTRATE COMPLEX where the enzyme goes to work (can put together or take apart a substrate.)3.) the enzyme and products separate: the enzyme is ready to work on another substrate.

Draw Enzyme Action:

Interactive

Enzymes

• remember all enzymes are proteins• * sometimes they need "helpers"; these helpers

are called COENZYMES (a.k.a. VITAMINS)

enzymes are named for the chemicals that they "go to work" on……..1.) enzyme names always end in -ASE

ex. LIPASE MALTASE LACTASE 2.) the first part is what their substrate isCartoon

FACTORS THAT INFLUENCE (affect) ENZYME ACTION:

1. temperature:

* the temperature at which enzymes are most effective is called the optimum temperature.

* If it gets too hot, the enzyme falls apart (called denatures) then it no longer works(like when you get a very high fever)

FACTORS THAT INFLUENCE (affect) ENZYME ACTION

2. pH (the ph scale)• the measure of how acidic or basic something

is• The pH at which enzymes are most effective is

called the optimum pH

FACTORS THAT INFLUENCE (affect) ENZYME ACTION

3. amounts of enzymes and substrates* adding more of either the enzyme or substrate

will increase the rate of the reaction...until you reach a point where the enzyme cannot work any faster- then the activity level of enzyme action levels off.