Digestive System Flashcards
What is digestion?
The mechanical and chemical break down of foods into forms the cell membranes can absorb
What does the digestive system consist of?
Alimentary canal and accessory organs
What does the alimentary canal consist of?
Consist of organs from the mouth to the anus
What type of accessory organs does the digestive system consist of?
Organs that empty secretions into the alimentary canal; food doesn’t pass through them
What 2 cavities does the alimentary canal pass through?
Thoracic and abdominopelvic
What 4 layers make up the alimentary canal walls, from innermost to outermost?
Mucosa, submucosa, muscularis and serosa
Which of the layers of the alimentary canal wall transports absorbed food molecules?
Submucosa
What are the 2 types of movements in the alimentary canal?
Mixing and propelling
What is peristalsis?
Ring of contractions progressing down the tube, propels food particles down the tract
What type of movement happens when rhythmical contractions occur in small sections in the muscle, and it does not move the food in one direction?
Mixing movements
What type of movement is peristalsis considered? And why?
Propelling movements because it moves food in one direction
How do parasympathetic impulses control digestive activity?
Increase activities of digestive system(secretion and motility)
What is the first part of the alimentary canal?
Mouth
What is mastication?
The mechanical break down of solid particles, and mixes them with saliva
What organ functions as the an organ of speech and sensory reception?
Mouth
What does the cheeks form?
Form the lateral walls of the mouth
What contains muscles for facial expression and chewing?
Cheeks
What portions does the palate consist of?
Hard and soft palate
What are the lymphatic masses on the side of the tongue?
Palatine tonsils
What are adenoids?
Pharyngeal tonsils; masses of lymphatic tissue in posterior wall of pharynx
What begins mechanical digestion?
Teeth
What are the incisor teeth used for?
Biting
What teeth help with grasping and tearing?
Canines
What do molars and premolars help with?
Grinding
What covers the crown of teeth?
Enamel
What makes up most of the tooth and surrounds pulp cavity?
Dentin
___________ holds root in place, along with ___________.
Periodontal ligament; cementum
What do the salivary glands secrete?
Saliva
What are the functions of saliva?
Helps moisten food particles and binds them together, and dissolves food so it can be tasted
What are the 3 pairs of major salivary glands?
Parotid glands, submandibular glands, and sublingual glands
What is the largest salivary gland and what does it secrete?
Parotid gland; secretes serous saliva with amylase
Where are the submandibular glands located and what do they secrete?
Floor of the mouth; secretes serous and mucous
What gland is located under the tongue and mainly secretes mucous?
Sublingual glands
What is the saliva made up of?
Enzymes and bicarbonate ions
What 2 types of secretory cells do salivary glands secrete?
Serous cells and mucous cells
What is salivary amylase?
Watery fluid containing a digestive enzyme
What organs have muscular walls, which function in swallowing and do help in food digestion?
Pharynx and esophagus
What organ extends from the nasal cavity to the esophagus?
Pharynx
What are the parts of the pharynx?
Nasopharynx, oropharynx, laryngopharynx
What tubular organ extends from the pharynx to the stomach?
Esophagus
What does amylase do?
It splits starch and glycogen into disaccharides
What is the purpose of mucus?
Mucus binds food particles and lubricates food while swallowing
What are the 3 stages of swallowing?
First, second and third stage
What is the first stage of swallowing?
Saliva is mixed with chewed food, forming a bolus
What is the second stage of swallowing?
Starts as good reaches oropharynx, stimulates sensory receptors and triggers swallowing reflexes
What protects the nasal cavity from food when swallowing and how?
The soft palate and uvula rise
The ________ closes off top of the larynx, to protect trachea.
Epiglottis
What happens in the third stage of swallowing?
Peristalsis transports food in the esophagus to the stomach
What is another name for esophageal sphincter and what does it do?
Cardiac sphincter and regulates food passage into stomach, and closes to prevent regurgitation of food
In what quadrant of the abdominal cavity is the stomach?
Left upper quadrant
What are the four parts of the stomach?
Cardia, fundus, body, pylorus
Describe the cardia of the stomach?
Region near opening of esophagus, contains lower esophageal sphincter
Describe the fundus of the stomach
Rounded area that rises above the cardia. It is a temporary food storage that sometime contains swallowed air.
What is the main portion of the stomach called? And where is it located?
The body, it lies between the fundus and the pylorus
Describe the pylorus of the stomach.
Distal portion, closest to the small intestine
What is the purpose of the pyloric sphincter?
Controls gastric emptying
What are the components of gastric juice?
Pepsinogen, pepsin, gastric lipase, hydrochloric acid, mucus, and instrinsic factors
Sympathetic impulses _________ gastric activity, while parasympathetic impulses ___________ gastric activity.
Decrease, increase
What is the purpose of gastric?
Increase gastric juice secretion
What hormonal regulation decreases gastric motility?
Cholecystokinin(CCK)
What hormone releases bile?
Cholecystokinin(CCK)
What helps absorb fat-soluble vitamins?
Bile
What hormone helps enhance appetite by increase secretion of Neuropeptide Y?
Grehlin
What hormone is secreted by adipocytes to suppress appetite?
Leptin
What are fat-soluble vitamins?
Vitamins A, D, E, and K
What are water-soluble vitamins?
Vitamins B and C
What the food restrictions for vegans?
no animal foods
What are ovo-vegetarians allowed to eat?
Eggs are allowed, but no dairy or meat
What are semi vegetarian allowed to eat?
Dairy, eggs, chicken and fish but no other meat is allowed
What is the cause of marasmus?
due to lack of calories and protein
What nutritional disorder is caused by protein starvation?
Kwashiorkor
