Unit 4-Digestive Flashcards
Where does resorption of water occur?
in large intesine
What is segmentation?
the rhythmic local contractions of muscle
What is defection?
elimination of waste
whats another name for short nerve plexuses?
intrinsic nerve plexuses
Difference between short and long nerve plexuses?
Short- stays in gastrointestinal tract
Long- doesn’t stay in just the gastrointestinal tract
What is the main role of the mesentary?
To take organs and attach it to the abdominal cavity
Retro
behind the paritemeal
Identify tissue found in the submucosa
dense irregular connective
Describe the layers present in the muscularis externa
One layer- Circular layer runs around; so when it contracts it will change the diameter
Second: external longitudnal layer; so when it contracts it will change the length
Identify the tissue found in the mucosa
epithilieum
How many layers are found in the muscularis externa
2
T/F : mucosa serves a protective function
true
Whats another name for oral cavity
buccal
Identify the pathway that is used for ingestion
oral cavity
What is the role of the roof(palate) portion of oral cavity?
separation of the oral cavity from the nasal cavity
What would happen if you didn’t have your tongue?
Wouldn’t be able to swallow well
Describe parotid glands
a type of salivary gland which contains serous glands
What is the role of serous glands
proudction of enzymes
What are the components that can be found in the saliva
Water, electrolytes, antibodies (IgA), amylase, mucin, lysosome, metabolic waste
What is mostly found in saliva
water
t/f: Saliva is highly acidic
false, Saliva is SLIGHTLY acidic
T/F: we only have one set of teeth
false we have two sets of teeth
How many teeth can be found in a set (s)
Primary: 20 teeth
Permanent: 32
What is the purpose of teeths?
mastication
What is mastication?
chewing
t/f: tooth is living structure
true
What is deglutition (basic answer)
swallowing
Identify the two phases that occur in deglutition
- buccal
- pharyngeal-esophageal
What is the role of globlet cells?
production of mucus
What do parietal cells secrete?
Hydrochloric acid and intrnsic factors
What organs make up the digestive system?
Alimentary canal and accessory digestive organs
Identify the organs that considered as accessory organs.
Teeth, tongue, salivary glands, liver, gallbladder, pancreas,
List the major steps that are involved in the digestive process
- Ingestion
- Propulsion
- Mechanical digestion
- Chemical digestion
- Absorption
- Defecation
What occurs in ingestion of the digestive system process?
The act of bringing food into the digestive system
T/F: Ingestion occurs in both the mouth and the large intestine.
False, ingestion ONLY occurs in the mouth
What occurs in propulsion of the digestive system process?
Describes the movement of material through the digestive tract
Identify the types of propulsion
Deglutition and peristalsis
Describe deglutition
- swallowing
- a form of propulsion
- This process can be both partial voluntary and partial involuntary
Describe peristalsis
- a form of propulsion
- involuntary process
- starts in the eosphagus
- wave-like smooth muscle contractions
What occurs in mechanical digestion of the digestive system process?
- physical breakdown of food
- mastication
- segmentation
- mixing
Describe physical breakdown of food in mechanical digestion
Turning big pieces of food into smaller pieces
Describe mixing of mechanical digestion
- stomach churns and mixes foods
- the tongue will move around the found which mixes the food with the saliva to assist in breaking down the food
Describe the mastication of mechanical digestion
- Chewing
- Mechanical digestion in the mouth
Describe segmentation of mechanical digestion
- encourages propulsion mixing
- alternating muscular contractions moves materials back and forth
What occurs in chemical digestion of the digestive system?
- Utilizing enzymes to aid in breaking food down into its building blocks
- Starts in the mouth-> continues in stomach-> finishes in the small intestine
Describe the alimentary canal
- Continuous, muscular and hollow canal
- opens to external environment on both ends
- we absorb things thru the walls of alimentary canal and leaves wastes in this canal that can then be excrete
- Everything within this canal is considered to be outside of the body
T/F: the alimentary canal ends in the anus and begins in the mouth and nasal cavity
False, ends in the anus and begins in the mouth
Describe what occurs when enzymes are used to break down into its building blocks
- Fats/lipids into fatty acids and glycerol
- carbohydrates in glucose
- proteins into amino acids
Describe what occurs when chemical digestion begins in the mouth, continues in the stomach and then finishes in the small intestine
Different nutrients are chemically digested in different parts of the alimentary canal
What occurs in absorption of the digestive system process?
Describes the movement of digested products from the lumen of the alimentary canal to the blood or lymphatic system
Describe the movement of digested material during absorption of digestion
Digested material has to pass thru musical membrane of the alimentary canal
What occurs in defecation of the digestive system process?
Elimination of waste
What is waste called for humans?
feces
List the sensory receptors that are applicable to the digestive system.
Stretch receptors, osmolarity receptors, pH receptors, receptors for certain molecules
What are sensors?
Sensory receptors
Describe what happens when sensory receptors are activated
they can decrease or increase activity of the digestive system such as smooth muscle contraction and secretion patterns
What is the role of receptors for certain molecules?
Certain receptors have the ability to detect whether proteins or fats are present in the food that has been digested
What are nerve plexuses?
Nerves that are present in the digestive system
Describe intrinsic plexi.
- utilizes the enteric nervous system
- have localized effects
Describe what occurs when intrinsic plexi utilize the enteric nervous system
- wont utilize the central nervous system
- nervous tracts don’t leave the digestive system
Describe an example thats applicable to intrinsic plexi
First stretch of the stomach will begin to activate the stomach
Describe extrinsic plexi
utilizes the central nervous system
Describe an example that is applicable to extrinsic plexi
- A sensory message is sent from the small intestine to the brain
- A motor message is then sent from the brain to the stomach
Describe the role that hormones can play in regards to the digestive system
glandular secretion of hormones can affect the digestive tract elsewhere in the body
Discuss what the mesentery
- a double layered peritoneum
- will anchor the abdominal organs to abdominal wall
Identify the four tunics that make up the digestive tract
- muscularis externa
- mucosa
- submucosa
- serosa
What tissue is found in the mucosa tunic of the digestive tract?
composed of epithelial tissue
- made up of mostly columnar epithelium and goblet cells
List the roles of mucosa
functions in absorption, protection, secretion of: mucus, enzymes, hormones
What tissue makes up the submucosa?
dense irregular connective tissue
What is contained in the submucosa?
lymphatic vessels, nerves, glands, blood vessels
What is the tissue/muscle found in the muscularis externa?
Smooth involuntary muscle
How does the muscularis externa utilize smooth muscle?
-works in mechanical digestion, mixing and movement
What is the serosa similar to?
adventitia
Discuss ways that the serosa is similar to adventitia.
- serosa occurs below the diaphragm while the adventitia occurs above the diaphragm
- esophagus has serosa on the lower portion while adventitia is found on the upper portion
Describe how serosa is related to the serous membrane
- Serosa is part of the serous membrane
- visceral peritoneum which acts as the outer covering of the abdominal organs
T/F: Intrinsic nerve plexus are the only type of nerve plexus that require the central nervous system to function.
false, intrinsic nerve plexus DON’T require the central nevrous system in order to function
Identify the types of intrinsic nerve plexus
- sub mucosal nerve plexus
- myenteric nerve plexus
What is a myenteric nerve plexus?
- Between two different layers of muscles
- Linked to movement or motility
What is a submucosa nerve plexus?
- Located in the submucosa
- Involves muscles and glands just oustide of submucosa
What is the role between submucosal nerve plexus and glands
This plexus acts on glands to secrete substances and the contraction of muscles
T/F: the central nervous system does not have the same effects to the same areas innervated by submucosal and myenteric
false
What is the role of the oral/buccal cavity?
- lips and cheeks will prevent food from escaping
- Only side of ingestion
Outside of ingestion what else does the oral buccal cavity include?
- chemical digestion, mechanical digestion, and propulsion
- for chemical digestion only have the starting of digestion of carbohydrates (starches)
List characteristics of the palate
- roof of the mouth
- changes from bony to soft to enable you to breathe while eating
- two portions
- contains the uvula to block the nasal cavity
Distinguish the the different portions that makeup the palate
- Soft: back part, fleshy
- Hard:front portion, bony, this portion of the palate can be used by the tongue to compact and compress food
List characteristics of the tongue
- muscular organ
- papillae
- this organ will move and mix food
- clumps food into bolus
- involved deglutition
Define a bolus
Ball-shaped mixture of food and saliva that was clumped together by the tongue
Distinguish the types of papillaery
- fungiform: taste buds
- filiform: most abundant and offers grip to move food around
List characteristics of the salivary glands
- cleans our mouth even when not eating
- contains enzymes
- fluids help to dissolve foods and moisten
Why is it necessary for there to be fluid present in the salivary glands?
Because the fluid allows for the salivary glands to become biologically active
What kind of enzymes can be found in the salivary glands?
Salivary amalyze which can help in breaking down starch
Distinguish the types of cells that can be found in the salivary glands
- serous
- mucous
- mixture of serous and mucous
Distinguish the types of salivary glands
- parotid salivary gland: back of oral cavity and contains serous cells
- submandibular gland: contains both serous and mucous cells
- sublingual salivary glands: underneath the tongue and contain mucous cells
Describe the circumstances for level of activity for sublingual salivary glands
When thinking of or actually engaging in eating activity will increase
What process do teeth utilize?
mastication
How many teeth are in our primary set?
20 total which will be acquired by the time a person is 2 years old
How many teeth are in our permanent set of teeth?
32
Describe the type of tissue found in the external sphincter of the large intestine)
skeletal
