Cornell Notes-Practice! Preparation for life beyond HIGH SCHOOL! Key Points for “BIOCHEMISTRY NOTES” (LEFT SIDE OF PAPER): -What are 3 parts of an atom? -What are 3 parts of an atom? -What do organic molecules contain? -What do organic molecules contain? -What are 2 substances that are inorganic? -What are 2 substances that are inorganic? -What are the “levels of organization?” -What are the “levels of organization?”

Atom- the smallest unit of an element that retains the chemical properties of that elementelement Atoms

Made of 3 parts protons, neutrons, electrons Protons = positive charge (+) + Neutrons = no charge Electrons = negative charge (-)

Organic Compounds Organic = contains carbon (made of carbon) *All living things are organic because they contain carbon! X X

Organic Compounds Organic = contains carbon (made of carbon)

2 Types of Molecules: Elements and Compounds Compound- made of two or more different kinds of atoms Element- made of only one kind of atom Oxygen O 2 Water H 2 O

Oxygen Carbon Hydrogen Nitrogen Phosphorus 5 Most Common Elements in Living Things

Levels of Organization Small to Large Body Systems Organs Tissues Cells Molecules Elements Atoms

Properties of Water Notes Water is POLAR Water molecules are cohesive Water molecules are adhesive

What are the properties of water? Water is POLAR Water molecules are cohesive Water molecules are adhesive Density property-Water is more dense as liquid than as a solid Water is a universal solvent.

Why is water considered “polar”? Water is POLAR Hydrogen has a positive charge. Oxygen has a negative charge.

What is cohesion? Water molecules are cohesive (they stick to each other!)

What is cohesion? Water molecules are cohesive (they stick to each other!) HYDROGEN BOND! Cohesion leads to surface tension

What is adhesion? Properties of Water Water is ADHESIVE (attracted to other types of molecules) Tape is adhesive… it sticks to stuff! The water molecules are like little magnets. They will be attracted to other molecules like soap, sugar, salt etc!

What property of water is shown here?

What is special about water’s density? Water is less dense as a solid than a liquid. Water is less dense as a solid than a liquid. What does this mean? What do you already know about density? What does this mean? What do you already know about density? Solid Liquid Gas Use the diagram to fill in molecules for a solid, liquid and gas. How would you arrange the “dots” (molecules)?

Just think…. Inside one drop of water is many tiny water molecules made up of… Just think…. Inside one drop of water is many tiny water molecules made up of… Hydrogen (+) and Oxygen (-)! Hydrogen (+) and Oxygen (-)!

What is special about water’s density? This is the normal molecule structure for solid, liquid and gas: This is the normal molecule structure for solid, liquid and gas:

What is special about water’s density? Ice is less dense as a solid so it floats! Ice is less dense as a solid so it floats!

Review… What are the properties of Water Water is POLAR Water molecules are cohesive Water molecules are adhesive Because of these properties, water is considered the UNIVERSAL SOLVENT! (water can dissolve almost anything!)