Digestive System Flashcards
1
Q
It is a group of organs and structures in the body responsible for breaking down food into nutrients, which the body uses for energy, growth, and repair. It also removes undigested and waste materials from the body.
A
Digestive system
It breaks down large organic molecules into smaller ones that can be absorbed in the body.
1
Q
Our digestive system cannot absorb _____ molecules.
A
complex
Note: That is the reason why Carbohydrates, Proteins, and Lipids needs to be breakdown into their simplest form.
2
Q
What is the simplest form of Carbohydrates?
A
Monosaccharides
3
Q
What is the simplest form of Protein?
A
Amino Acid
4
Q
What is the simplest form of Lipids?
A
Fatty acid or Glycerol
5
Q
It is difficult to digest because it is a type of carbohydrate that the human body lacks the enzymes to break down.
It passes largely intact through the digestive system.
Examples: corn, grass
A
Fiber
Note: We eat fiber to add bulk on our stool. If we have more bulk on our stool, we will be able to defecate everyday and it will prevent constipation.
6
Q
What are the Functions of Digestive System?
A
- Ingestion of solids and liquids
- Digestion of organic molecules
- Absorption of nutrients
- Elimination of waste
7
Q
The absorption of nutrients primarily happens in the _________. It is the most important organ for nutrient absorption in the digestive system.
A
small intestine
8
Q
The elimination of waste, also known as excretion, occurs in the _____________ and culminates in the expulsion of feces through the rectum and anus. This process removes undigested food, waste products, and other substances that the body cannot use.
A
large intestine
Note: There is still absorption process going on here but it only absorbs water, electrolytes, and vitamins produced by gut bacteria (e.g., vitamin K).
9
Q
What are the 2 Components of the Digestive System?
A
Gastrointestinal tract (GI tract) and Associated organs
10
Q
It is a continuous (long) tube from the mouth to the anus. It is responsible for digestion, absorption, and waste elimination.
PATHWAY OF FOOD
A
Gastrointestinal tract or GI tract
11
Q
These organs assist in digestion (release of enzymes for chemical digestion) but are not part of the GI tract itself.
A
Associated organs
Note: It can also be called as Accessory organs
12
Q
What are the associated organs of the Digestive system?
A
- Salivary glands
- Liver
- Gallbladder
- Pancreas
13
Q
The digestive tract consists of the following. What are these? List in order.
A
- Oral cavity (mouth)
- Pharynx
- Esophagus
- Stomach
- Small intestine
- Large intestine
- Rectum
- Anus
REMEMBER THE ACRONYM OPESS - LRA
14
Q
The wall of the digestive tract (GI tract) is composed of several layers, each serving a specific function in digestion and absorption. From the innermost layer to the outermost. What are these?
A
- Mucosa
- Submucosa
- Muscularis
- Serosa / Adventitia
REMEMBER THE ACRONYM MS-MS
15
Q
The Layers of the tract wall are also termed __________ just like the blood vessel.
A
tunics
Remember that the wall of blood vessels are:
- Tunica intima
- Tunica media
- Tunica adventitia
16
Q
It is the innermost layer of the Digestive tract wall which secretes mucus and comes in contact with the food.
A
Mucosa
17
Q
It is the layer under / over the mucosa. It contains blood vessels, nerves, small glands.
The connection of nerves or what we call as innervations is located in this layer.
A
Submucosa
Note: Digestive tract can be reconnect. Example: If you have cancer in the colon, the Doctors can cut and reconnect the organs for it to function like before. And this happens because of the secrets of the layers of our digestive tract.
CUT, CUT, and RECONNECT
18
Q
JUST FAMILIARIZE!
It is a serious condition that affects newborns.
It is a congenital condition in which there is a lack of nerve cells (ganglion cells) in a segment of the colon. This leads to an enlargement (megacolon) of the colon due to the inability of the affected portion of the bowel to perform normal contractions (peristalsis).
A
Ganglion megacolon
Surgical removal of the affected segment of the colon. This allows the healthy, ganglion cell-containing portions of the colon to function properly.
CUT, CUT, and RECONNECT
19
Q
It is the layer under / over submucosa composed of smooth muscles.
A
Muscularis
20
Q
It is the outermost layer of the digestive tract wall.
It has 2. What are these?
A
SEROSA / ADVENTITIA
21
Q
Outermost layer. Anything below the diaphragm is called?
This is because peritoneum is present.
A
Serosa
22
Q
Outermost layer. Anything above the diaphragm is called?
This is because there is no peritoneum.
A
Adventitia
23
Q
Is Peritoneum part of the Digestive System?
A
NO
This is just a space (Peritonial Cavity).
24
Peritoneum —the serous membrane that lines the abdominal cavity and covers most of the abdominal organs, have **3 Parts**. What are these?
* Mesenteries
* Lesser omentum
* Greater omentum
25
It is the **connective tissue that holds our GI.**
These are folds of the peritoneum that attach the intestines to the posterior abdominal wall, allowing for the passage of blood vessels, nerves, and lymphatics to the intestines.
**It makes our organs stay in place**
**Mesenteries**
Note: It primarily support and supply organs (especially the intestines) with blood vessels and nerves.
26
It is a double layer of peritoneum that connects the **stomach** and **duodenum** (first part of the small intestine) to the **liver.**
**Lesser omentum**
Note: It connects the stomach and duodenum to the liver.
27
It is a large apron-like fold of peritoneum that hangs down from the **greater curvature of the stomach** and the **first part of the duodenum (colon).**
**Greater omentum**
Note: It is much larger, draping over the intestines, and functions as a fat storage and protective covering.
28
It is the **inflammation of the peritoneum**, the thin membrane that lines the abdominal cavity and covers the abdominal organs.
The most common cause, often resulting from a rupture or perforation in an organ of the digestive system, such as the **appendix** (in appendicitis), **stomach** (in peptic ulcers), **intestines** (in diverticulitis), or the **gallbladder** (in cholecystitis).
**Peritonitis**
Note: Ang gagawin dito, huhugasan yung mga organs since they are infected tapos ipa-patch yung mga butas, like yung na rupture na appendix.
Tawag sa ganito is "exploratory laparotomy"
29
It is the **first part** of the digestive system which contains **Salivary glands** that produces saliva which contains enzyme to break down carbohydrates.
**Oral Cavity or Mouth**
Note: This is where physical and chemical digestion s starts.
30
It is found in the mouth and it **produces saliva** to break down food. It **cleanse the mouth** and at the same time, responsible for **dissolving and moistening of food.**
Salivary gland
31
What is the **specific salivary enzyme** that breaks down carbohydrates?
Salivary Amylase
32
What is the **salivary enzyme** that are active against **bacteria**.
**Lysozyme**
Note: It can react or control bacteria
33
It is a **muscular organ** in the mouth that **house taste buds and mucus**.
Tongue
34
It is the bony part found at the **top of your mouth, behind the teeth**.
**Hard palate**
Note: Clinical significance is for **Cleft Palate**
* A congenital defect where the hard palate does not form properly, leaving a gap between the oral and nasal cavities. It needs to undergo operation immediately because when they are able to speak. It is difficult to correct their speaking.
35
It is the **small, fleshy, teardrop-shaped structure that hangs down** from the back of the soft palate at the roof of the mouth. It is visible when you open your mouth wide and say "ah."
**Uvula**
Note: This is important for swallowing. A lot of people called this tonsil but it's not.
36
It can detect and trap microorganisms. If it is **reddish** that means you have a tonsillitis. So, they are the first line of defense on our mouth.
Tonsils
37
Types of teeth
* **Incisors** - Found at the front of the mouth, with four in the upper jaw (maxilla) and four in the lower jaw (mandible).
* **Canine (Pangil)** - Next to the incisors, with two in the upper jaw and two in the lower jaw. Pointed and cone-shaped with a sharp edge.
* **Premolars** - Found between the canines and molars, with four in the upper jaw and four in the lower jaw. Broader than canines, with two cusps (points) on their biting surface.
* **Molars** - At the back of the mouth, with six in the upper jaw and six in the lower jaw (including wisdom teeth).
38
The adult human has ___ permanent teeth.
**32**
39
Children have ___ primary teeth (baby teeth)
**20**
40
Typically, baby teeth start to fall out around the age of ______.
**6-8**. Average is 7 years old.
41
When permanent teeth are damaged, this can be used.
This are removable dental appliances designed to replace missing teeth and restore function, aesthetics, and comfort for individuals with tooth loss. They can be made for partial or complete replacement of teeth in one or both jaws.
Dentures
42
What is the **first teeth to erupt (6 months)**?
Incisor (upper)
43
This is the roof of oral cavity.
**Palate**
Note:
* **Hard palate:** Back of the teeth. Anterior part
* **Soft palate:** Located at the back of the mouth, behind the hard palate. Posterior part
44
What are the **three major types of Salivary Glands**?
* Parotid gland
* Sublingual gland
* Submandibular gland
45
Found in front of and slightly below the ears, extending to the angle of the jaw. It is the **largest salivary glands.**
**Parotid gland**
Clinical significance:
* Prone to infections, such as **mumps or Parotitis**, or blockages caused by salivary stones.
Note: Americans are scared of Mumps because it can cause **orchitis** (inflammation of the testes) and if they have it, it can result to sterility problem (mababaog).
46
Found **beneath the tongue** in the floor of the mouth.
The **smallest** of the major salivary glands.
Sublingual gland
47
Situated **beneath the lower jaw (mandible)** on both sides of the neck.
**Medium-sized** salivary glands.
Submandibular gland
48
Also known as the **throat which connects the mouth to the esophagus**.
Pharynx
49
The pharynx is divided into **three main regions** based on location:
What are these?
* **Nasopharynx** - breathing
* **Oropharynx** - digestive
* **Laryngopharynx** - breathing
50
It is the **tube that connects the pharynx to the stomach**. It is mainly to transport food to the stomach.
Esophagus
51
The esophagus has **two muscular structures** that regulate the flow of food and liquids through the esophagus, ensuring proper digestion and preventing reflux. What are these?
* Upper Esophageal Sphincter (UES)
* Lower Esophageal Sphincter (LES)
52
Lower Esophageal Sphincter is also known as what?
**Cardiac Sphincter**
Note: This is the culprit of heartburn.
53
It is a common condition characterized by a **burning sensation in the chest or throat, often after eating or lying down.** It occurs when stomach acid backs up into the esophagus (the tube that connects the mouth to the stomach).
Caused by excessive caffeine, smoking, eating, drinking, and pregnancy too (pressure of the uterus).
**Heartburn**
It occurs when gastric juices **regurgitate (backflow)** into the esophagus.
54
This is the **mixture of food and saliva** that forms in the mouth during chewing.
Bolus
55
**Swallowing**, also known as deglutition, is a complex process that involves the coordinated movement of food or liquid from the mouth to the stomach. It occurs in **three distinct phases**. What are these?
* Voluntary phase
* Pharyngeal phase
* Esophageal phase
56
This phase is **under voluntary control**. It starts when food or liquid is chewed and formed into a **bolus** (a small, rounded mass of food).
Location: Mouth
Voluntary phase
57
This is the act of **swallowing the food.**
This phase is **involuntary** and is initiated once the bolus enters the pharynx.
Location: Pharynx
**Pharyngeal phase**
Note: The problem here lies on the epiglottis. It is very important that it is closed. So that you will not aspirate food.
Note 2: People that can't breathe properly are NPO (Nothing per Orem) bawal pakainin. As their diet should be modified.
58
It is a feeding tube that can be used to provide nutrition and hydration to **stroke** patients who have difficulty swallowing.
Nasogastric tube (NGT)
59
Protects the airway by covering the trachea.
Epiglottis
60
This phase is also **involuntary** and involves the movement of the bolus through the esophagus to the stomach.
Location: Esophagus
**Esophageal phase**
61
It is the movement of the digestive tract in a **wave like rhythm, pattern, contraction**.
Peristalsis
62
It is a key organ in the digestive system that plays a central role in the breakdown of food. It is located between the esophagus and the small intestine. It is **storage tank for food**. It can hold up to 2 liters of food or more daw if matakaw ka.
Stomach
63
The Stomach contains **Four (4) Secretions**. What are these?
* Mucus
* Hydrochloric acid (HCl)
* Pepsin
* Gastric lipase
64
This is for **protection**. It protects stomach from its own acid. Without it, you can have **ulcer**.
Some medications can cause acid.
**Mucus**
Note: Non-steroidal anti-inflammatory drugs (NSAIDs) are a class of medications that reduce pain, inflammation, and fever. However, it causes ulcer or stomach acid.
Ex: Mefenamic acid
65
It is for **chemical digestion** as it has a pH level of 3.
It can even dissolve a spoon. That's how strong it is.
Hydrochloric acid (HCl)
66
It is a **protein digesting enzyme** secreted by the stomach.
Pepsin
67
It breaks down **lipids** (fats) into fatty acids and monoglycerides.
Fat digestion
Gastric lipase
68
It is **both Physical and Chemical digestion** because of the *churning action*.
Stomach
69
Substances to be ingested through the mouth from the outside is called what?
Food
70
When the food is mixed with saliva, it is called what?
Bolus
71
When the bolus (food + saliva) goes to the stomach and mixed with stomach acid, it is called what?
This is the **paste-like** substance that forms when food begins to be broken down.
Chyme
72
There are **three phases of gastric secretion regulation** during digestion. These phases help the digestive system prepare for and respond to food intake, ensuring proper breakdown and absorption of nutrients.
* Cephalic phase
* Gastric phase
* Intestinal phase
73
This is the **first phase** and the stomach secretions are triggered by **sight, smell, taste, or thought of food.**
***Increased Gastric Acid Production***
**Cephalic phase**
Its all in your BRAIN. **Hypothalamus** is the part of the brain that causes hunger and thirst.
(Natatakam ka palang)
74
This is the **second phase**. Triggered by the presence of food in the stomach (NAKAIN MO NA).
There will be distention of stomach (paglaki).
***Increased Gastric Acid Production***
Gastric Phase
75
This is the **third phase**.
Trigger: Presence of chyme in the small intestine (**duodenum**).
***Decreased gastric acid production***
Intestinal phase
76
The lower end of the stomach is called what?
Pylorus
77
It is a long, coiled tube where most digestion and nutrient absorption occurs.
**Small intestine**
78
The small intestine is divided into three main sections. What are these?
* Duodenum
* Jejunum
* Ileum
79
The **first and shortest part (25 cm long [10-12 inches]) of the small intestine**, directly connected to the stomach.
It is shaped letter C and contains absorptive cells. It has microvilli in lining and contains **bile**
Duodenum
80
The small intestine, particularly the duodenum contains absorptive cells like enterocytes, goblet cells, granular cells, and endocrine cells.
What is the function of goblet cells?
**To produce mucus.**
81
What does bile digest?
It digest fats.
82
The **middle section** of the small intestine, following the duodenum. It is **2.5 meters long** and it **absorbs nutrients.**
Jejunum
83
The **final and longest section** of the small intestine approximately 3.5 meters long, connecting to the large intestine at the **ileocecal junction**
Ileum
84
The ______ of the small intestine is the innermost layer of its wall and plays a critical role in digestion, absorption, and immunity. It is highly specialized and structured to maximize surface area for efficient nutrient absorption.
Mucosa
85
The mucosa of the small intestine is simple columnar Epithelium with **four major cell types**. What are these?
* Absorptive cells
* Goblet cells
* Granular cells
* Endocrine cells
86
**Primary cells for nutrient absorption.**
Contain **microvilli**, which form the brush border, greatly increasing the surface area for absorption.
Example: **enterocytes for absorption**
Absorptive cells
87
Cells that **secrete mucus**, which lubricates and **protects the intestinal lining** from mechanical damage and digestive enzymes.
Goblet cells
88
These are cells which may help protect the intestinal epithelium from bacteria.
**It has antibacterial property**
Example: Lysozyme
Granular cells
89
These are cells that produce **regulatory hormones**.
Endocrine cells
90
These are **tubular glands found in the mucosa** of the small intestine and large intestine. They are located at the **base of the villi**.
They mainly **help in the multiplication of cells (cell growth)**.
The **intestinal glands**, also known as the **crypts of Lieberkühn**
91
These are **specialized glands located in the submucosa of the duodenum**, which is the first part of the small intestine.
These glands are unique to the duodenum and serve specific functions to protect and prepare the intestine for digestion.
Duodenal glands
92
These are enzymes that **catalyzes the breakdown of protein into amino acids** for absorption.
Peptidases
93
These are **enzymes that catalyze the breakdown of disaccharides (double sugars) into their constituent monosaccharides**, which can be absorbed by the body.
Disaccharidases
94
It is the **propulsion of food**. It is the movement that occurs not only on the small intestine but throughout the GI tract.
When we say propulsion, it is the action of driving or pushing forward the contents along the tract.
**Peristaltic contractions**
Note: One direction only
95
It is the **mixing of food**. It is the movement that only happens in the small intestine and it is about moving back and forth to mix the chyme.
Basically about **mixing contents in place**.
**Segmental contractions**
Note: Opposite direction
96
It is the **largest organ inside the body**. It weighs about **3 lbs**.
It is a vital organ located in the upper-right portion of the abdominal cavity, beneath the diaphragm and above the stomach. It plays a central role in metabolism, detoxification, digestion, and various physiological processes.
Liver
97
The liver is divided into **4 lobes**. What are these?
* Right lobe (largest)
* Left lobe
* Caudate lobe (posterior)
* Quadrate lobe (near the gallbladder)
98
It is also known as the **"gateway to the liver**," is a deep fissure on the inferior surface of the liver.
It serves as the **entry and exit point** for several vital structures.
**Porta (Porta Hepatis)**
Contains:
* The **hepatic artery** (oxygenated blood supply to the liver).
* The **portal vein** (nutrient-rich blood from the digestive tract).
* The **common hepatic duct** (carries bile away from the liver).
99
The portal triad is consist of 3. What are these?
* Hepatic duct
* Hepatic portal vein
* Hepatic artery
***Note that these are just branches***
100
Is Porta and Portal Triad the same?
No.
* The **porta hepatis** is an anatomical landmark where large blood vessels and ducts enter or leave the liver.
* The **portal triad** refers to the smaller branches of these vessels and ducts within the liver lobules, crucial for the liver's microscopic functions.
101
This is the **divisions of liver** with portal triad at corner.
Lobules
102
This is the **margin between each lobule.**
Separated by hepatic sinusoids.
Hepatic chord
103
This **contain phagocytic cells** that remove foreign particles from blood.
Hepatic sinusoids
104
This is the **center of each lobule**. This is where mixed blood flows and forms hepatic veins.
Central vein
105
What are the **4 Liver Ducts**?
* Hepatic duct
* Common hepatic duct
* Cystic duct
* Common bile duct
106
* Refers to the **right hepatic duct and left hepatic duct.**
* These ducts **collect bile from the right and left lobes** of the liver, respectively.
* They join together to form the common hepatic duct.
Hepatic duct
107
It is **formed from left and right hepatic duct**.
Common hepatic duct
108
Connects the **gallbladder** to the **common hepatic duct**.
Cystic duct
109
Formed by the **union of the common hepatic duct and the cystic duct.**
Carries bile from the liver and gallbladder to the duodenum (the first part of the small intestine).
Common bile duct
110
It is a **muscular valve that controls the flow of bile and pancreatic juices into the duodenum** (the first part of the small intestine). It plays a critical role in digestion, especially the breakdown of fats and neutralization of stomach acid.
Sphincter of oddi
111
What are the **Functions of the Liver**?
* Digestive and excretory functions
* Stores and processes nutrients
* Detoxifies harmful chemicals
* Synthesizes new molecules
* Secretes 700 milliliters of bile each day
112
It is a fluid produced by the liver and stored in the gallbladder that helps with digestion and waste removal.
It dilutes and neutralizes stomach acid and **breaks down fats**.
Bile
113
The coordinated control of bile secretion and release in response to food ingestion.
FAMILIARIZE
* **Brain** detects food ➡ activates **vagus nerve**.
* **Vagus nerve** stimulates gallbladder, liver, and sphincter of Oddi for bile production and release.
* **Secretin** is released due to acidic chyme ➡ stimulates bile production.
* **CCK (Cholecystokinin)** is released in response to fats/proteins ➡ causes gallbladder contraction and sphincter relaxation for bile and enzyme release.
114
It is a vital glandular organ with both **exocrine** and **endocrine** functions, essential for digestion and metabolic regulation. It is located in the upper abdomen, behind the stomach, and is connected to the duodenum.
Pancreas
115
The Structure of Pancreas is composed of 3. What are these?
**Head:**
* The widest part, nestled in the curve of the duodenum.
**Body:**
* The central part, which extends across the abdomen.
**Tail:**
* The narrow end, located near the spleen.
116
Endocrine tissues of pancreas have this and this is the one **that produces insulin and glucagon**.
**Clusters of cells within the pancreas that secrete hormones into the bloodstream.**
**Islets of Langerhans**
Note:
**Insulin**: Lowers blood glucose levels by promoting glucose uptake into cells.
**Glucagon**: Raises blood glucose levels by stimulating glucose release from the liver.
117
What does the pancreas **exocrine tissues** produces that travel through the ducts?
**digestive enzymes**
118
What **digestive enzymes does the exocrine tissues produces**?
**Acini or Acinar cells**
Note: These are pecialized cells that produce digestive enzymes.
119
UNDER Pancreatic Secretions
What are the **3 Major Protein-digesting enzymes**?
* **Trypsin**
* Chymotrypsin
* Carboxypeptidase
Note: Trypsin is the only important to remember here.
120
One of the major protein-digesting enzymes is **Trypsin**.
What is the Inactive form of trypsin?
**Trypsinogen**
Note: Activated by the enzyme **enteropeptidase or Entero Endocrine cell** (produced by the small intestine) into trypsin.
121
This refers to the **self-digestion of tissues by the body's own digestive enzymes**. It occurs when enzymes, particularly those secreted by the pancreas, are activated prematurely or inappropriately, leading to tissue damage and inflammation.
Autodigestion
122
It is the **most common condition associated with autodigestion.**
Triggered by:
* Gallstones blocking the pancreatic duct.
* Alcohol abuse.
* Trauma or surgery.
* High triglycerides or calcium levels.
Acute pancreatitis
123
It is the **final part of the gastrointestinal (GI) tract, primarily responsible for absorbing water, electrolytes, and vitamins while forming and storing feces**. It is approximately **1.5** meters long and larger in diameter compared to the small intestine.
Large intestine (colon)
124
The Structure of large intestine is composed of 4. What are these?
* Cecum
* Colon
* Rectum
* Anal canal
125
The **first portion of large intestine**. It is connected to the ileum via the **ileocecal valve**, which prevents backflow.
It also **hosts the appendix**, a small lymphoid structure with immune functions.
Cecum
126
The ______ is **1.5 meters long** and it is connected to the cecum.
It contains 4 section which are ascending, Transverse, descending, sigmoid regions.
**Colon**
* **Ascending Colon:** Runs upward on the right side of the abdomen.
* **Transverse Colon:** Extends across the abdomen.
* **Descending Colon:** Runs downward on the left side.
* **Sigmoid Colon:** S-shaped curve leading to the rectum.
127
It is the straight tube that **begins at sigmoid colon** and ends at the anal canal
**Rectum**
Note: This is where suppository is inserted.
128
Ends in the anus, controlled by the **internal** (involuntary) and **external** (voluntary) sphincters for defecation.
* Food takes 18-24 hours to pass through.
**Anal Canal**
129
This is the product of water, indigestible food, and microbes.
**Feces**
Note: That the microbes on our Feces synthesize vitamin K which is a blood Clotting factor.
It also contains E.coli and it forms gas. This is why we tend to fart more when we need to poop.
130
These are **small pouches or sacculations in the colon that give it a segmented appearance**.
**Haustra**
Note:
**Haustral Contractions:**
* Slow segmental movements that mix and compact fecal material.
131
There is still absorption in the large intestine and it is the absorption of what?
Water
132
The Anal Canal has **2 Sphincter**. What are these?
* **Internal anal Sphincter** - Involuntary (Autonomic)
* **External anal sphincter** - Voluntary (Somatic)
133
We have **4 Digestion Process**. What are these?
* Digestion
* Propulsion
* Absorption
* Defecation
134
What do you call the process of **breakdown of food that occurs in the stomach and mouth**?
Digestion
135
What do you call the process by which the **food moves through digestive tract and it includes swallowing and peristalsis**?
Propulsion
136
The Digestive process primarily in **duodenum and jejunum of small intestine**.
Absorption
137
The digestive process that is about the **elimination of waste** in the form of feces.
Defecation
