Gemini Personal Unit 3 Honors Bio

Endothermic Reactions (Anabolic Reactions)

Put together small to large molecules, use free energy, and store it in new molecules (e.g., dehydration synthesis)

Exothermic Reactions (Catabolic Reactions)

Break down large to small molecules and release free energy (e.g., hydrolysis)

Metabolism

Sum of all anabolic & catabolic reactions (or endothermic & exothermic reactions)

Reaction Speed

Increased by increasing temperature or concentration

ATP (Adenosine Triphosphate)

Chemical energy used to store & release energy in the cell

Oxidation Reaction

Removes electrons (usually on hydrogen) and releases free energy

Reduction Reaction

Gains electrons and gains energy

ATP Structure

Adenine, sugar (ribose), and 3 phosphate groups

Energy Storage & Release in ATP

Breaking the bond between the 2nd & 3rd phosphate groups releases energy; forming a bond stores energy

Goal of Enzymes

To break apart larger molecules to use monomers & get energy out of bonds in between monomers

Enzyme

Catalyst that speeds up reactions by bringing reactants together & aligning them to react; not used up in the reaction

Activation Energy

Energy required for a reaction to begin (lowered by catalysts)

Denature

Disrupt folding, which messes up the function

Non-competitive Inhibition

Molecule attaches to an enzyme (not at the active site) and causes a shape change so the substrate can't bind

Competitive Inhibition

Molecule other than the substrate blocks the active site so the substrate can't insert

Enzyme Activity Changes

Active site changes due to temperature or pH changes, so the substrate can't bind

Trypsin (Digestion)

Secreted by pancreas into small intestine; macromolecule: proteins -> amino acids

Pepsin (Digestion)

Utilized in stomach; macromolecule: proteins -> amino acids

Amylase (Digestion)

Utilized in mouth/saliva; macromolecule: starch -> simple sugar

Lipase (Digestion)

Produced in mouth, stomach, pancreas; utilized in small intestine; macromolecule: lipids -> fatty acid & glycerol

Nuclease (Digestion)

Produced in pancreas & small intestine; utilized in small intestine; macromolecule: nucleic acids -> nucleotides

Large Intestines (Colon)

End of tract; reabsorbs water, absorbs vitamins produced by bacteria, and eliminates feces/waste products

Intracellular Digestion

Digestion inside the cell (found in plants & single-celled organisms)

Extracellular Digestion

Digestion takes place outside cells (found in most animals)

Human Digestion

Break down macromolecules in order to be absorbed & used as matter & energy

Mechanical / Physical Digestion

Physically break food into smaller pieces

Chemical Digestion

Enzymes break food into smaller molecules to be absorbed

Mouth (Digestive System)

Part of the digestive system/tube itself; contains teeth (mechanical) and saliva (chemical)

Saliva

Contains salivary amylase that begins to break down starch to disaccharide

Epiglottis

Flap that blocks trachea to prevent food & water from entering lungs

Esophagus

2 layers of muscle connecting pharynx to stomach; uses peristalsis (muscle contractions) to move food

Stomach

3 layers of smooth muscle; mechanical digestion via muscle contractions to churn food; chemical digestion via gastric glands

Mucus (Stomach)

Lubricates and protects stomach lining from acids & enzymes

Hydrochloric Acid (HCl)

Activates enzymes, dissolves minerals, & kills bacteria

Pepsin (Stomach)

Breaks complex proteins to smaller polypeptides & amino acids

Sphincters

Thick ring of muscle that opens & closes to allow food in & out of the stomach

Cardiac Sphincter

Lower esophageal sphincter between esophagus & stomach (top of stomach)

Pyloric Sphincter

Between stomach & small intestine (bottom of stomach)

Liver

Not part of digestive tract; stores glycogen, detoxifies substances from blood, and secretes bile to help break up fat droplets

Gallbladder

Stores bile until required for digestion

Pancreas

Not part of digestive tract; secretes pancreatic fluid (digestive enzymes) into small intestines and neutralizes acid/pH from stomach

Small Intestine

Receives secretions from gallbladder & pancreas to complete digestion; consists of duodenum, jejunum, and ileum

Villi

Finger-like projections lining the small intestine that increase surface area and contain blood vessels & lymph to absorb water & nutrients