Biochemistry

The chemical basis of life

Based on organic (carbon) chemistry

All living things are made of matter.

Matter: material governed by laws of inertia (resistance to change in motion)

The smallest organized unit of matter that is living is called a cell.

Atomic structure video

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Matter of the same composition is a substance.

Ex: pure sugar, pure salt, etc

Substances can change.

Living matter is made up of different substances.

Therefore life can change.

Periodic table of elements … do you need to know them all for this class?

What elements do producers need?

C HOPKNS café Managed By My Cousin Mo Cline

CHOPKNS Ca Fe Mg B Mn Cu Zn Mo Cl

Chemical reactions lead to changes in substance or matter.

Occurs when electrons are transferred between two atoms

covalent or ionic

Substance types1. Atom = electron + proton + neutron

2. Element: one atom with set number of protons(ex: nitrogen)

3. Compound: two or more atoms in fixed ratio (ex: water H2O) Q.What is in the beaker?

4. Molecule: 1 unit of a compound (ex: water H2O is 1 molecule of water) Q. How many molecules of water are in the beaker?

To maintain life the following are needed.

96% of living matter: carbon, hydrogen, oxygen, nitrogen

4% of living matter: calcium, potassium, phosphorus, sulfur, sodium, chlorine, magnesium, iron, trace elements

Why is carbon the basis for life?

It has 4 electrons in its outer electron shell.

Octet rule: The most stable elements have 8 electrons in its outer shell, with few exceptions.

Carbon forms 4 covalent bonds to fulfill the octet rule.

Covalent bond = two atoms sharing electrons

“Strong” Relatively stable Hydrogen, oxygen,

and nitrogen can readily form covalent bonds with carbon.

Covalent bonding video

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Ions = electrically charged matter Ions form when electrons are lost or gained. Ionic bonds form when a positive ion is attracted to a

negative ion.

Ionic bonding video

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Making polymers

When monomers (single units) transfer electrons between one another, they form dimers.

Adding more monomers form polymers.

Important polymers & complex molecules

Polysaccharides Proteins Nucleic acids Lipids

Methane Acetylene Butadiene Benzene Isooctane

Section 2-3

Figure 2-11 Carbon Compounds

Starch

Glucose

Section 2-3

Figure 2-13 A Starch

Lipids

General structure Alanine Serine

Section 2-3

Amino group Carboxyl group

Figure 2-16 Amino Acids

Aminoacids

Figure 2-17 A Protein

Nucleic acids