Digestion, Metabolism, Nutrition Flashcards
Organic Molecules
Carbohydrates, Lipids, Proteins
Carbohydrates
Bonded sugars
Primary Source of making energy
What happens if there is excess sugar?
Stored in liver and muscle cells as glycogen
Converted into adipose (fat) tissue as triglycerides
Lipids- Triglycerides
Glycerol + 3 fatty acid chains
Excess stored in adipose tissue
What are triglycerides used for?
Used for long term energy storage
What happens during metabolism?
Catabolism: breakdown of large organic molecules into smaller ones
Anabolism: creation of larger or new substances
Digestive System Functions
Ingestion: Taking in food/ liquids into mouth
Propulsion: Moving substances
Digestion: Breaking down substances
Absorption: Nutrients move into blood
Defecation: Removal of indigestible substances
Hard Palate
Maxillae and palatine bones
Where does the tongue force food against during chewing and swallowing?
The Hard Palate
Uvulva
The free edge of the soft palate
What are the mastication muscles?
Temporalis
Masseter
Lateral and Medial Pterygoids
What nerve innervates the mastication muscles?
Mandibular nerve
(Cranial Nerve V3)
What do the mastication muscles do?
Move the jaw
Accessory muscles that position food
Buccinator (VII)
Digastric (V3 & VII)
Geniohyoid &Tongue (XII)
Teeth types
Incisors
Cuspids (canines)
Bicuspids (premolars)
Molars
Incisors (4)
Rip and nip
Cuspids (canines) (2)
Slash, tear, and shear
Bicuspeds (premolars) (2)
Larger and complexely surfaced for chewing and grinding
Molars (3)
Large grinding surfaces
The 3 phases before food enters the stomach
Buccal Phase
Pharyngeal phase
esophageal phase
Buccal Phase
Salivary glands lubricate food
Chemical Digestion of carbohydrates
Tonge & tongue muscles (CNXII) press food against hard palate and towards pharynx
Soft palate elevates (CNX) to seal off nasal cavity
Bolus gets moved to the oropharynx
Pharyngeal phase
Nasopharynx is closed
Food continues to go into oropharynx
Hyoid and larynx muscles contract and epiglottis covers larynx
Superior pharyngeal constrictors contract (CNX) to pull food into pharynx
Middle and inferior pharyngeal constrictors contract (CNX) which moves food into esophagus
Esophageal phase
Peristalis occurs to push substances along the tube
Cardiac sphincter opens and bolus enters the stomach
Stomach during digestion
Bolus enters and becomes chyme
Starts chemical digestion of proteins