Gi tract

Question 1

How do cavitities happen

Answer 1

Bacteria produce acid which erode enamel and damage dentin.

Question 2

What happens if decay moves past the dentin

Answer 2

reach the pulp inside the tooth, causing inflammation (pulpitis)

Question 3

What protects teeth from cavitities

Answer 3

Saliva

Question 4

What happens if gingivitis is left untreated

Answer 4

can progress to periodontal disease, where the infection spreads to the tissues supporting the teeth. This leads to the formation of small infection pockets between the teeth and gums, causing teeth to become loose and potentially fall out.

Question 5

Name carcinomas of the oral cavity.

Answer 5

-Leukoplakia – white lesions
-Erythroplakia-depressed red lesions frequently
-Oral cancers readily metastasize – many nearby LN in head and neck (associated with smokers and drinkers)
-

Question 6

What condition is it called when you have a hard time swallowing

Answer 6

Esophageal sphinster dysfuncition

Question 7

Explain the types of Esophagus sphinter – LES dysfunction

Answer 7

two types
1) Achalasia: Sphinter fails to open
2) Incompetent cardiac sphincter (Stays open and causes reflux).

Question 8

What are some Complications of incompetent cardiac sphincter

Answer 8

1)Reflux Esophagitis: Irritation/ inflammation of esophagus lining due to constant acid exposure= can increase the risk of asthma.
2)Ulcers and Scarring: The lining of the esophagus can get damaged and develop ulcers, leading to scar tissue that can make the esophagus narrower.
3)Barrett Esophagus: The normal squamous cells in the esophagus change into a different type (columnar cells), which can increase the risk of developing esophageal cancer.

Question 9

What are the causes of Causes of Esophageal Obstruction

Answer 9

1)Carcinoma (Esophageal Cancer)
What happens: A tumor can develop anywhere in the esophagus, narrowing its passage (lumen) and growing into surrounding tissues.
2)Food Impaction(not swallow well)/Stricture (Narrowing)
3)Hiatal Hernia/rings:Part of the stomach pushes up through the diaphragm into the chest, which can press on the esophagus and cause blockages or symptoms of reflux.

Question 10

What is Mallory-Weiss Syndrome

Answer 10

occurs when forceful retching or vomiting (often from excess alcohol intake or conditions like bulimia) causes tears in the lining of the esophagus.

Question 11

What is Boerhaave Syndrome

Answer 11

involving a complete rupture (full-thickness tear) of the esophagus. (life threatning)

Question 12

What is usually the main cause of Acute Gastritis

Answer 12

inflammation of the lining of the stomach
nonsteroidal anti-inflammatory drugs (NSAIDs) that inhibit cyclooxygenase (COX) enzyme: Aspirin, ibuprofen, naproxen
COX-1: Promotes synthesis of prostaglandin that protects gastric mucosa
COX-2: Promotes synthesis of prostaglandin that mediates inflammation

Question 13

How does helicobacter pylori work

Answer 13

gram-negative bacteria that lives on the surface of the stomach lining.
H. pylori produces urease, which turns urea into ammonia. The ammonia neutralizes stomach acid, helping the bacteria survive. It also breaks down the stomach’s protective mucus, making the stomach more vulnerable to damage.

Question 14

What can h.pylori do

Answer 14

-Chronic gastritis,Increased cancer risk , Peptic ulcers.

Question 15

What is Acute Enteritis/ what causes it

Answer 15

Common Acute Enteritis caused by Rotavirus and Norovirus (highly contageous)
self-limiting (goes away on its own)

Question 16

Explain the mechanism behind why loos stool is associated with lactose intolarance.

Answer 16

body can’t digest lactose becuase lack of enzyme, Unabsorbed lactose in increases osomotic pressure which pulls water into the bowl.
Bacteria in the colon ferment the unabsorbed lactose, producing lactic acid and gas

Question 17

Explain how celiac disease works

Answer 17

T cells, attacks the small intestine when gluten is consumed, causing inflammation. This inflammation increases the risk of intestinal cancer over time. Also the vili shrink over time which causes malabsorption and diarrhea

Question 18

Explain Irritable Bowel Syndrome

Answer 18

crampy abdominal discomfort.Diagnosis made by exclusion – no structural or biochemical anomalies

Question 19

People who remove appendix are more prone to what?

Answer 19

Increased C. Diff and GI infection
-evidence that the appendix plays a role in the immune system. Removing it has been linked to a higher risk of gastrointestinal (GI) infections.

Question 20

Explain appendacitis

Answer 20

The appendix’s narrow opening can get blocked by fecal material. This blockage causes poor drainage, leading to a buildup of pressure inside the appendix.

Question 21

Chronic enteritis includes ..

Answer 21

two major types of IBD
1) crohns disease:the entire bowel wall becomes inflamed. THICKNING of bowl wall.
2)Ulcerative colitis: affects the colon and rectum, with inflammation of only the inner lining of the bowel. inner lining inflamation

Question 22

What causes antibiotic-associated colitis?

Answer 22

Broad-spectrum antibiotics destroy normal intestinal bacteria, allowing the growth of Clostridium difficile (C. diff),

Question 23

Where is High intestinal obstruction and low intestinal obstruction located in

Answer 23

High intestinal obstruction :Small intestines
low intestinal obstruction:large intestine

Question 24

What are Adhesions

Answer 24

bands of connective tissue that form in the abdomen, often after surgery. leading to an obstruction (blockage) in the bowel near where the adhesion forms.

Question 25

How does A hernia occure

Answer 25

when a part of the bowel pushes through a small opening in the abdominal wall. This creates a pouch called a hernial sac

Question 26

Explain the terms in how hernias react

Answer 26

Reducible hernia: Herniated loop of bowel can be pushed back into abdominal cavity

Incarcerated hernia: Cannot be pushed back

Strangulated hernia:Loop of bowel is tightly constricted, obstructing the blood supply to the herniated bowel; requires prompt surgical intervention to prevent infarction

Question 27

Explain Volvulus

Answer 27

bowel twists around itself and the mesentery (the tissue that supports the intestines and contains blood vessels). This twisting causes a bowel obstruction and can cut off the blood supply.

Question 28

How does Mesenteric Thrombosis
happen

Answer 28

Thrombosis of the superior mesenteric artery occurs when this artery, which supplies blood to the small intestine and the first half of the colon, becomes blocked

Question 29

Explain Diverticulitis

Answer 29

Diverticulosis is when small pouches, called diverticula, form in weak spots of the colon wall. This happens when a low-fiber diet makes it harder to move stool through the colon, increasing pressure and pushing these pouches out.

Question 30

Development of colorectal cancers are commonly associated with what types of mutations

Answer 30

APC gene

Question 31

Why is there typically no blockage in the proximal part of the large intestine.

Answer 31

Cancer in the cecum and proximal colon (the first part of the colon) usually doesn’t cause a blockage because this part of the bowel is larger and the contents are soft

Question 32

What are Hemorrhoids

Answer 32

varicose veins in rectum. Can be caused by pregnancy and low fiber fiet.

Question 33

Explain Anorexia nervosa and Bulimia nervosa.

Answer 33

Anorexia nervosa: person has an intense fear of gaining weight. restricts their diet
Bulimia nervosa: person binge eats and then tries to prevent weight gain through purging behaviors like vomiting, excessive exercise, or using laxatives.