Get out a pencil. Warm-Up

Warm-up Grab the digestive system diagram. Fill it out, and glue it into your journal.

Physical Change Affects the form of a substance Can changes states (solid, liquid, gas) Changes shape or size

Chemical Change A usually irreversible chemical reaction involving the rearrangement of atoms of one or more substances and a change in their chemical properties or composition, resulting in the formation of at least one new substance

The body’s cells cannot use an entire hamburger The body’s cells cannot use an entire hamburger. The hamburger must be broken down (digested) for the body to use it as a source of energy. Digestion breaks down food into small molecules that can be used at the cellular level.

Organic Molecules Make up all living matter Made mostly of carbon bonded with Hydrogen CHNOPS Carbon Hydrogen Nitrogen Oxygen Phosphorus Sulfur

Organic molecules all contain carbon bonded to hydrogen and a combination of certain other elements. (nitrogen, oxygen, phosphorus, sulfur) Organic Inorganic CH4 (methane) CaCl (calcium chloride) C8H10N4O2 (caffeine) NaOH (sodium hydroxide) C5H5N5O (guanine) CO2 (carbon dioxide)

Copy the table and determine if it is organic or inorganic. Substance Chemical Formula Originates from a living thing Organic Inorganic Table salt NaCl Sugar C6H12O6 Aluminum can Al Carbonic acid H2CO3 Rust Fe2O3 Citric acid (fruit) C6H8O7 sand SiO2

Found in living organisms and classified into four major categories: Carbohydrates Lipids Proteins Nucleic acids Usually contain large numbers of carbon, hydrogen, and oxygen atoms.

Large organic molecules are made up of many single molecules linked together. Smaller molecules are called monomers. When several monomers are linked together, they form a polymer. Proteins are made up of several amino acids linked together. Carbohydrates are made up of several sugar molecules.

When the body needs energy, large carbohydrates molecules need to be broken down into glucose so that the cells can use the molecules. The process of breaking down organic molecules is similar to the Explore activities in which you had to break the chain of people to get through the opening.

The reverse happens as well The reverse happens as well. Monomers can be joined together to form polymers, such as when sugars are linked together to form a carbohydrate.

Digestion causes large food particles to be broken down into smaller ones usable by cells. Carbohydrates, proteins, and lipids contain large chains of carbon, hydrogen, and oxygen. These large, long molecules are broken down into different, smaller molecules by chemical changes that occur during digestion. Carbohydrates begin breaking down into more simple sugars in the mouth. Proteins begin to be digested in the stomach, while the breakdown of fats begins in the small intestine.

Chemical energy in food (potential energy) is transformed into heat energy and mechanical energy (kinetic energy).

The human body breaks down organic molecules so they are usable at the cellular level, such as sugar used as fuel for the cell.

Chyme The stomach makes digestive juices that help to break down our food into a thick liquid.