Diffusion• Diffusion: movement of particles from an

area of high concentration to an area of low concentration–Particles move along a concentration

gradient – no energy is used!!!–Particles move until distribution of particles

is even throughout – dynamic equilibrium

Diffusion is important for cells– Diffusion is one way that substances like

Na+, K+, Ca2+ can move in and out of cells

Focus Activity

1. What are the 3 most common elements in the human body & their %’s?

2. Which of these elements is always found in organic compounds?

Biochemistry

Notes Chapter 6. 3 – Life Substances and Organic

Chemistry• Organic chemistry is the study of Carbon-

based compounds.

• All living things are composed of organic compounds.

What makes Carbon Special?

1. Carbon can covalently bond with up to four other atoms.

2. Carbon can form immensely diverse compounds, such as long

chains and rings

Methane with 1 Carbon atom

DNA with tens of Billions of Carbon atoms

There are 4 Fundamental Organic Molecules used in our bodies

• 1. Carbohydrates (sugars and starches)

• 2. Lipids (fats, waxes, oils, steroid hormones)

• 3. Proteins – (enzymes, muscles tissue, cell structures)

• 4. Nucleic Acids – (DNA and RNA which are our genetic material)

Fundamental Biomolecules“CHNO”

Amino acids Monosaccharides Nucleotide Fatty Acids

Proteins Nucleic Acids LipidsCarbohydrates

monomermonomer

monomermonomer

Function Function Function Function

1. Energy storage 2. Plant cellulose

1. Enzymes2. Cell Structural components 3. Immunity

1. Long term energy storage2. Protective coverings 3. Insulation

1. Genetic material

Examples of Proteins• Enzymes

• Muscle tissue

• Keratin (hair, fingernails, horns)

Special Notes for Proteins• Enzymes

– Speed up chemical reactions in the body– function using the Lock and Key Model– Enzymes usually end in ASE

• Protein test is Biuret’s reagent

Examples Carbohydrates

• Glucose

• Sucrose

• fructose

• starches

• glycogen

Special Notes for Carbohydrates

• Ratio of C:H:O is 1:2:1 (C6H12O6)

• Starch Test is Iodine

• Sugar Test is Benedict’s Reagent

• Oftens ends in OSE

Examples of Nucleic Acids• DNA (deoxyribonucleic acid)

• RNA (ribonucleic acid) is used for making proteins

Special Notes for Nucleic Acids

• Nucleotide always consist of three parts

Examples of Lipids

• Cell membrane

• Fats

• Oils

• Sterols– Cholesterol

Special Notes for Lipids• Saturated fats have

no double bonds

• Unsaturated fats have 1 double bond

• Test is the paper bag test (look for a grease spot)

Osmosis• Type of diffusion in which only water moves• Water will move from a high concentration to a

low concentration• Useful in cell membranes that are selectively

permeable – Only certain materials are allowed to move freely in

and out of the cell through the membrane

Nucleic Acids• Consist of C, H, O, nitrogen, and phosphorus

• Building blocks (monomers) are nucleotides

• Each nucleotide consist of three parts:– Phosphate– Sugar– Nitrogenous bases

Lipid functions• Long term Energy storage• Insulation• Protective coverings• Cell membranes

• Tested for using the paper bag or grease spot test