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 Click on image to play video.

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 types 1. 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 H 2 O) Q.What is in the beaker? 4. Molecule: 1 unit of a compound (ex: water H 2 O 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 Click on image to play video.

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 Click on image to play video.

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

MethaneAcetyleneButadieneBenzeneIsooctane Section 2-3 Figure 2-11 Carbon Compounds

Starch Glucose Section 2-3 Figure 2-13 A Starch

Lipids

General structureAlanineSerine Section 2-3 Amino groupCarboxyl group Figure 2-16 Amino Acids

Amino acids Figure 2-17 A Protein

Nucleic acids