L16- Digestion (last Test) Flashcards
Cell respiration
Biochemical pathway for ATP production
Metabolism
Sum of all chemical reactions in the body ( catabolism + anabolism of fat, protein, carbohydrates)
Digestion
Occurs in a tube through the middle of the body ( extracellular)
What are the four functions of the digestion system?
Ingest, digest, move, absorb
Ingest
- take in nutrients
Nutrients
Chemicals we need and cannot make
Why are nutrients important to ingest?
Required for fuel, structure, cellular processes
Digest
Convert polymers to monomers/ subunits
- protein ➡️ amino acids
- carbohydrates ➡️ glucose
- triglycerides ➡️ fatty acids, glycerol
What are the two ways to digest food?
Mechanically- teeth & smooth muscle
Chemical- enzymes
Move
Transports through intestinal tract ( smooth muscle)
Absorption occurs in what two locations and what is absorbed?
Blood - amino acids & glucose
Lymphatic capillaries- fats
What are the five nutrients we need?
- fuel molecules, amino acids, water, minerals, vitamins
Fuel molecules
Glucose and fatty acids ( make ATP)
Amino acids
Make proteins
Water
- a solvent
- maintains osmolarity & blood pressure
- helps with chemical reactions
Minerals
Used in Bone, cofactors, nerve/ muscle functions, 2nd messengers, oxygen transport
Vitamins
Used for coenzymes
Gastrointestinal (gi) tract includes
Oral cavity, esophagus, stomach, small intestine & large intestine
What are the three parts of the small intestine
Duodenum, jejunum, ileum
The accessory organs part of the digestive system
Salivary glands, liver, pancreas
The accessory organs are specialized exocrine glands
TRUE or FALSE
True; they secrete into the digestive tract
Goblet cells
Secrete mucus to allow movement
Generalized functions of the gi tract
- mechanical digestion
- absorption
- enzymatic digestion
- secretion of digestive enzymes & hormones
Gi tract secretes
Digestive enzymes and hormones
Generalized functions of the accessory organs
- secrete digestive juice & mucus into tube
What are the 3 layers of the Gi tract?
(Inner - out)
- Mucosa
- Submucosa
- Muscularis
- Serosa
Mucosa (mucus layer)
- inner lining of Gi tract
- Secretes and absorbs
Submucosa
Highly vascular to absorb nutrients
Muscularis
- 2 layers of smooth muscle
Mechanical digestion and propels food
Serosa
Serous membrane - secretes serous fluid to reduce friction
Rugae
Folds in the stomach
Functions of the stomach
- storage (primarily)
- mechanically digests
- secretes HCL
-secretes Pepsinogen - secretes mucus = preventing damage to lining of stomach