Chapter 24: Digestive System Flashcards
When chewing food what does it becomes once it dissolves?
bolus
Once it becomes bolus, where does it go?
to the pharynx then the esophagus to drain in the stomach
Where in the small intestine does the chyme go first after it forms in the stomach?
the duodenum which is where most digestion occurs
Where in the small intestine will you find the most nutrients being absorbed?
the jejunum
What part of the small intestine meets with the cecum?
the ileum
From the cecum, where does what was ingested go through?
ascending colon > transverse colon > descending colon > sigmoid colon > rectum/anus
Name the functions of these in the digestive system: ingestion, mechanical processing, digestion, secretion, absorption, compaction
- ingestion: putting food into the mouth
- mechanical processing: chewing/swallowing
- digestion: break down food in order to be processed
- secretion: secretes things like enzymes, acid
- absorption: once collected, they get absorbed, leave lumen and go into the blood stream
- compaction: feces get excreted out of the body (anus)
What are the four layers of the digestive tract?
mucosa, submucosa, muscular layer, serosa
What happens within the muscular layer where the two smooth muscle layers circular and longitudinal can be found?
- circular: when contracting the diameter of the lumen decreases
- longitudinal: when contracting the length of the lumen gets shorter
If an organ does not have a serous membrane, what does it have?
adevntitia
What holds the transverse colon?
transverse mesocolon
What holds the liver to the diaphragm?
falciform ligament
What holds the liver to the stomach?
lesser omentum
What holds or attaches the stomach to the transverse colon?
greater omentum
What mesentary holds the small intestine in place?
mesenteric proper
What holds the large intestine in place?
sigmoid mesocolon
What is the name and function of the two movements to help push and mix food?
- peristalsis: forward motion that moves the bolus from the mouth to the anus
- segmentation: turning motion that mixes the bolus within the small intestine
What happens in the oral cavity involving food?
- a conscience decision to put food in the mouth
- once food enters deciding if it is good or not
- mastification: chemical processing of food, helps shape the food
- deglutition: swallowing; tongue/pharync/soft palate
What are aldenoids?
inflammed pharyngeal tonsils
When the lips are open, what is the name of the structure that is found and the upper and bottom portion of the lips and the bottom of the tongue?
frenulum of upper/lower lip
What are the types of saliva’s found in the (3) salivary glands?
- parotid: serous saliva; biggest gland
- sublingual: mucus & serous saliva, secretes the largest amount
- submandibular: smaller gland; mucus saliva
What is another name for “baby teeth” ?
deciduous teeth
What is the name of the part of our teeth that we see that is outside the gingiva?
the crown
What part of our teeth has no living cells, easy to get infected, the hardest and makes our teeth white?
enamel
Describe what happens in the (3) phases: buccal, pharyngeal, esophageal phase? (mention details)
- buccal phase: the toungue pushes the bolus to the oral pharynx (hypoglossal nerve makes the tongue move)
- pharyngeal phase: bolus arrives at oral pharynx; epiglottis closes the larynx, forces food down esophagus
- esophageal phase: moves bolus down to the stomach via peristalsis (upper/lower sphincters)
What happens as you go down the esophagus?
decrease in the amount of skeletal fiber (aid in swallowing reflex), but an increase in the smooth muscle fiber (pushing bolus towards stomach via peristalsis)
What three organs have adventitia, but not the serous membrane?
esophagus, retcum, pharynx
What is known as the fold found within the walls of the lumen that is bumpy?
rugae
What is the function of rugae?
- gripping action to help the mixture of bolus better
What happens when the stomach is ready for digestion? (what is released?)
chyme gets released
What is the function of sphincters?
provide one way flow
What is significant or the functions of these three cells: parietal, chief, G cells
- parietal: HCl helps with chemical digestion + killing pathogens (change in pH)
- chief cells: pepsinogen gets secreted; pepsin is what allows the digestion of proteins
- G cells: gastrin gets secreted; the parietal, chief cells and muscular contraction get activated to work
Which cell gets activated when we either think about or see food?
G cells get activated by the vagus nerve
Where does the chyme pass through in the stomach to reach the small intestine?
pyloric sphincter
Where does the chyme get pushed to when contraction occurs?
from the duodenum, jejunum then to the ileum
What are some characteristics of the duodenum, jejunum, and the ileum?
- duodenum: most digestion occurs here, the c-shape helps to trap the chyme
- jejunum: nutrient absorption
- ileum: helps fight bacteria
Where in the large intestine do feces get stored?
sigmoid colon
