Chemistry you need to know! Chemistry in BIOLOGY? Chemistry you need to know!

Atoms,molecules,ions,OH MY! What is an Atom? An atom is the smallest part of an ELEMENT That retains all the properties of that element It is electrically neutral, spherical in shape And made of protons, electrons and neutrons. What is an Element? A pure substance that cannot be broken down into simpler substances by chemical or physical means An element is made of atoms (the number of protons determines the element)

Elements of Life Elements of Life 96%  Hydrogen (H), Oxygen (O), Nitrogen (N), and Carbon (C) 3%  P, S, Ca, K, Na, Mg, Fe, Cl 1%  other trace elements

Molecules an electrically neutral group of two or more atoms held together by chemical bonds Molecules as components of matter are common in organic substances Examples Oxygen (O2 ) 2 oxygen held together by Covalent bonds Water (H2O) 1 oxygen and 2 hydrogen held together by hydrogen bonds Glucose (C6H12O6) 6 carbons 12 hydrogens and 6 oxygens (SUGAR) More complex molecules that we will see later!

What is a Reaction? Energy REACTANTS PRODUCT

Chemical Reaction for Breathing C6H12O6 + 6O2 = 6CO2 + H2O + Energy  What are the Reactants? What are the Products?

Water Most Abundant compound in all organisms Required for life (this is why life on other planets is not possible and why we focus on Mars- has ice which means water is probably underneath) 70% of Earth’s surface is water! 75-65% of the human Body is water! (75% of newborns/ 65% of adults) Unique properties that make it so important for life

Oxygen Waste product of photosynthesis (released by plants) Vital for human life Found in other comounds Required for many life processes such as breathing, metabolism and energy

Carbon dioxide A waste product of human respiration and the burning of fossil fuels Used by plants to perform photosynthesis Responsible for the greenhouse effect