Module 6 Flashcards
(49 cards)
The 3 primary functions of the digestive system of food molecules that can then be used for both energy and building blocks for the entire body are what?
- Aquisition
- digestion
- absorption
where does energy come from?
the organic molecules that we consume (carbs, fats, proteins)
organic molecules are broken down by what two things?
- Aerobic cellular respiration
- ATP
Carbohydrates: ___ Kcal/gram
Fats: __ Kcal/gram
Proteins: __ Kcal/gram
Carbohydrates: 4 Kcal/gram
Fats: 9 Kcal/gram
Proteins: 4 Kcal/gram
What should we eat to get the proper amounts of energy and the proper number of building blocks to maintain homeostasis in the human body?
Carbohydrates: 250-800 g/day; 2/3 starch, 1/3 (sucrose & lactose)
Fats: 25-160 g/day
Proteins: 40-50 g/day
(can differ depending on size of person and amount of exercise)
The two basic processes that occur in the digestive system
- Digestion
- Absorption
the breakdown of food either mechanically or chemically
digestion
the movement of food from the lumen of the gastrointestinal tract into the blood or lymph fluid
absorption
what is the process of physically separating two different food molecules to increase the surface area of food for an increase in the efficiency of chemical digestion?
provide an example
Mechanical digestion
ex: Chewing: teeth tear apart large clumps of food into smaller clumps of food that are easier to swallow and allow access of enzymes to more of the food’s surface at any given time
Oftentimes the GI tract is described as a “tube within a tube” because the inside of the GI tract is technically outside the body. (T/F)
True
What is the flow of the GI Tract?
Mouth & Pharynx > Esophagus > stomach > Small Intestine > Large Intestine > Rectum > Anus
What provides the first bit of mechanical digestion?
Chewing or “mastication”
How many pairs of salivary glands add saliva to food?
Three
when a single molecule of a food substance is broken down into smaller molecules that can be moved across the wall of the intestine in absorption?
provide an example
Chemical digestion
ex: Enzymes catalyze the chemical reactions that break apart food molecules.
What does saliva contain that lubricates food for swallowing?
Mucous
The wall of the GI tract consists of what 4 basic layers?
- mucosa (innermost)
- submucosa
- muscularis externa
- serosa (outermost, surface)
What does water in saliva help with?
breaking ionic bonds in food substances to facilitate taste
What is the role of salivary amylase?
start the digestion of carbohydrates
What tube leads from the mouth to the stomach?
Esophagus
T or F the mucosa consists of 3 layers
True
Peristaltic movements in the esophagus help with what?
moving food along the path
determine each layer of the mucosa as the following: Lamina propria, mucous membrane, muscularis mucosae.
- smooth muscle that contracts the mucosa into folds to stir the lumenal contents and promote contact between the digested material and the mucosal surface.
- composed of epithelial cells called “enterocytes”, absorptive cells, and endocrine cells including goblet cells that secrete mucous and endocrine cells that secrete hormones
- contains connective tissue that includes blood vessels, nerves, lymphatic vessels, lymph nodules, and Peyer’s patches.
- muscularis mucosae
- mucous membrane
- lamina propria
What three parts is the stomach composed with?
- fundus
- body
- antrum
the fundus, the body, and the antrum are about 1.______ ml when empty but can stretch to over 2._______ ml when full.
- 50 ml
- 1000 ml