Science, Digestive System Flashcards
Definition of digestion
Digestion is the breakdown of larger molecules of food into smaller molecules of food.
What is physical (may sometimes be called mechanical) digestion? Where does it take place
- Involves the physical breakdown of food into smaller pieces
- Takes place mainly in the mouth (chewing) and stomach (churning and mixing)
What is chemical digestion? Where does it take place?
- Involves the breakdown of large food molecules into smaller, more absorbable forms through chemical reactions
- Mainly takes place in stomach, a bit in the small intestine
Which chemicals are involved in digestion?
- Saliva in the mouth contains amylase for carbohydrate digestion
- Gastric juices in the stomach contain hydrochloric acid and pepsin for protein digestion
- Pancreatic enzymes (amylase, lipase, proteases) and bile in the small intestine aid in the digestion of carbohydrates, fats, and proteins
- Intestinal enzymes (e.g., peptidases, sucrase, lactase, maltase) further break down molecules in the small intestine
What is peristalsis
- Peristalsis is a series of coordinated muscular contractions that propel food through the digestive tract
- It involves rhythmic squeezing and relaxation of muscles in the esophagus, stomach, and intestines
- Peristalsis helps move food along the digestive system and aids in mechanical digestion
In which organ is water absorbed in the digestive system
- Water is primarily absorbed in the large intestine (specifically the colon)
- The colon absorbs water from undigested food, resulting in the formation of solid feces
What are enzymes
- Enzymes are biological catalysts that help to speed up reactions
- Enzymes are not used up when they speed reactions, so they can be reused
- Enzymes catalyze (not only) digestion reactions breaking down large food molecules into smaller food molecules
- Specific enzymes help to catalyze the digestion (break down) of specific large food molecules
What are the different enzymes and their location in the digestive system
Carbohydrase - Mouth, pancreas, and small intestine
Protease - Stomach, pancreas, and small intestine
Lipase - Pancreas, and small intestine
Name the food molecule, the enzyme that breaks it down, and the product
Proteins - Protease - Amino acids
Lipids - Lipase - Fatty acids and glycerol
Carbohydrates - Amylase - Simple sugars (glucose, fructose, etc.)
In which organ are small food molecules absorbed, what is the structure that makes this process more efficient
- Small food molecules are primarily absorbed in the small intestine
- The inner lining of the small intestine is covered with tiny finger-like projections called villi
- Villi increase the surface area available for absorption, and each villus contains microvilli, further enhancing absorption efficiency
List the parts of the digestive system
- Salivary Glands
- Tongue
- Epiglottis
- Esophagus
- Liver
- Stomach
- Gallbladder Duodenum
- Pancreas
- Ileum (Small intestine)
- Colon (Large intestine)
- Cecum
- Apendix
- Rectum
- Anus
What is the function of the salivary glands
- Produces saliva
- Moistens food
- Contains enzymes for digestion
What is the function of the tongue
- Helps with chewing and swallowing
- Contains taste buds for sensing flavors
- Helps in speech production
What is the function of the epiglottis
- Covers the trachea during swallowing
- Prevents food from entering the windpipe
What is the function of the esophagus
- Transports food from the mouth to the stomach
- Uses muscle contractions (peristalsis) for movement
