Bio-Chemistry What is it? BIO

Bio VS Chem Biology refers to the study of living things Chemistry is the study of the composition of matter and reactions between different substances Biochemistry is the study of the reactions that occur in living things. We study it because the chemistry of our bodies (pH, temperature, etc.) have a strong influence on how we function.

Organic VS Inorganic Inorganic – Molecules or compounds that are not from a living thing Organic – Molecules or compounds that are typically found in living things (these contain a hydrogen bonded to a carbon) Organic compounds always have carbon and hydrogen, but typically have nitrogen and oxygen as well. These four elements (carbon, hydrogen ,oxygen, and nitrogen) are the most abundant elements found in living things

Organic Molecules Which of the following compounds are organic? Water (H2O) Glucose (C6H12O6) Carbon Dioxide (CO2) Oxygen (O2) Urea (CH4N2O) Salt (NaCl) How did you determine this?

Organic Compounds There are four classes of organic compounds: Carbohydrates Proteins Lipids Nucleic Acids These are the molecules that you (and ALL living things) are made of

4 Important Molecule Types Carbohydrates Sugars (anything sweet) Grains (pasta, bread, rice, cereal, etc.) Lipids Fats (oil, butter, grease, etc.) Proteins Meats (fish, eggs, steak, beans, etc.) Nucleic Acids DNA and RNA (found in every living cell)

Indicators Substances used to test the presence of a specific substance Many times an indicator will change color when it combines with its specific molecule Benedict’s Solution – turns from blue to yellow in the presence of glucose Iodine – changes from amber to dark blue in the presence of starch Paper Towel – turns shiny when a lipid is placed on its surface To find DNA we use many different indicators

Biochemistry Temperature and pH can affect the bonds and structure of certain molecules, so it is very important that our bodies stay at the appropriate pH and temperature (this is why we perform homeostasis) Temperature is a measure of how quickly molecules are moving; the faster the molecules are moving the higher the temperature is. pH is a measure of how acidic or basic a liquid solution is.

pH The pH scale goes from 0-14 Below 7 is considered acidic 7 is neutral (water) Above 7 is considered basic The farther away from 7 the number gets the more acidic or basic something gets For example vinegar has a pH of 3, but sulfuric acid (so acidic it can burn through skin) has a pH of less than 1

Enzymes All living things contain enzymes Enzymes are proteins that allow chemical reactions to occur (ex: cellular respiration, protein synthesis, photosynthesis, digestion, etc) Enzymes work best at a specific temperature and pH This is why our bodies must maintain homeostasis (so our enzymes can work properly)

Enzymes Enzymes are substrate specific (this means they only bind to specific molecules) Example: Saliva contains amylase, an enzyme that breaks down starch So, only molecules or cells with certain receptors will bind to the enzyme This prevents enzymes from digesting everything they come in contact with

Digestion Digestion is the process by which large molecules are broken down into their smaller subunits Our digestive systems contain special chemicals that break down the food we eat Example: Our saliva contains amylase which breaks down starch into simple sugars like glucose.

Synthesis Synthesis is the process of attaching small molecules together to make a larger molecule Many times this is done by removing a water molecules therefore dehydration synthesis Example: When you attach a bunch of molecules to glucose together you make a starch molecule