Unit 2: Energy, Enzymes & Digestion

Exergonic Reaction

A chemical reaction which releases energy

Endergonic

A chemical reaction that requires an input of energy

Enzyme

A molecule that can speed up chemical reaction by lowering the amount of energy needed

• Substrate →specific molecule enzyme acts on

• Active site →Area on surface that an enzyme acts

Inhibitor

A molecule that can interfere with an enzymes ability to bind to its molecule

• Competitive inhibitor - binds to portion of active cite

• Noncompetitive inhibitor - Bind to another portion of the enzyme and cause shape change that alters the active site

Digestive tract

Mouth → Esophagus → Stomach →Gallbladder →Small intestine→Large Intestine →Rectum →Anus

Mouth

1. Mechanical →Chewing and swallowing

2. Chemical →amylase and lipase breaking down carbs, lipids

Stomach

Turns food into chyme and transports to small intestine

1. Mechanical →turns and breaks food down

2. Chemical digestion → Hcl+Pepsin breaks down proteins

   • Lipase breaks down lipids

High PH levels are optimal conditions for pepsin and helps breakdown food

Small intestine

Breaks food into smaller molecules

1. Carbs →amylase, maltose, sucratose, lactace

2. Lipids → lipase, bile

3. Proteins →peptides

4. Nucleotide → Nuclease

Villi outlining the surface area absorbs nutrients, water, and electrolytes

Large intestine

Absorbs water, vitamins, electrolytes

Rectum + Anus

Waste is stored until eliminated out of body

Coenzyme

Changes the shape of active sites to help substrates fit e

• EX: drugs

Gallbladder

Stores bile

Liver

Makes bile

Pancreas

Makes amylase, lipase, nuclease

Length of digestive tract

Carnivores have a shorter digestive tract than herbivores and omnivores