Small Intestine

Question 1

What is the small intestine also called?

Answer 1

Small bowel

Question 2

How long is the slam intestine?

Answer 2

Around 6 metres long

Question 3

What does the small intestine comprise of?

Answer 3

• Duodenum
• Jejunum
• Ilium

Question 4

Where in the alimentary system is the primary site for digestion and absorption?

Answer 4

The small intestines

Question 5

What is meant by the small intestines being ‘partially retroperitoneal’?

Answer 5

• Peritoneum is a lining - holds things in place, prevents the pelvis from falling
• Kept roughly in the same position so prevents gravity from working on it
• Mesentery - double fold of peritoneum

Question 6

What is the peritoneum?

Answer 6

The serous membrane lining the cavity of the abdomen and covering abdominal organs

Question 7

What is mesothelium?

Answer 7

• A serous membrane
• A layer of tissue that covers and protects your internal organs. It allows them to move smoothly against each other and other structures

Question 8

What is parietal peritoneum?

Answer 8

• On the outside - lines the abdominal wall

Question 9

What is visceral peritoneum?

Answer 9

• Layer that goes around all the organs
• A continuation of parietal peritoneum reflected at various places over the viscera, forming a complete covering for the stomach, spleen, liver, intestines from the distal duodenum to the upper end of the rectum, uterus and ovaries; it also partially covers some of the abdominal organs

Question 10

What is mesentery?

Answer 10

Double fold of peritoneum

Question 11

What is Omentum?

Answer 11

• A double fold of peritoneum that folds around the stomach - wraps and hangs down like an apron
• Fatty tissue
• Function - starts moving inside you - wraps around area where there is a pathology and tries to minimise area of infection

Question 12

What part of the small intestine does most digestion occur?

Answer 12

The duodenum

Question 13

What does the duodenum receive from the stomach?

Answer 13

Chyme

Question 14

How long is the duodenum?

Answer 14

Short length

Question 15

What do Brunner’s glands in the duodenum secrete?

Answer 15

There glands produce alkaline mucous, which neutralises acid from the stomach as it enters the duodenum. As long as Brunner’s glands function normally, the mucous helps protect the duodenal lining

Question 16

What is the name of the common bile duct that secretes into the duodenum?

Answer 16

The Sphincter of Oddi

Question 17

What does the duodenum receive from the common bile duct (sphincter if Oddi)?

Answer 17

• Bile

- Pancreatic ‘juice’

Question 18

Where does the duodenum end?

Answer 18

At the duodenojejunal junction (cannot determine exactly where that is)

Question 19

What hormone is used to induce secretion of bile from the common bile duct in the duodenum?

Answer 19

CCK - Cholecystokinin

Question 20

What is cholecystokinin?

Answer 20

A hormone that is secreted when chyme enters the duodenum which causes the movement of chyme

Question 21

What are duodenal papillae?

Answer 21

Elevated openings that are found on the duodenum

Question 22

Where is the major duodenal papillae located?

Answer 22

In the descending part of the duodenum

Question 23

What are the 4 parts of the duodenum?

Answer 23

• Superior
• Descending
• Inferior
• Ascending

Question 24

What are the arteries that supply the duodenum?

Answer 24

• Celiac artery
• Superior pancreaticoduodenal artery
• Inferior pancreaticoduodenal artery
• Superior mesenteric artery

Question 25

Where are duodenal ulcers most commonly found?

Answer 25

- In the posterior wall of the superior part

Question 26

What is peritonitis?

Answer 26

Wide spread infection of the peritoneum

Question 27

What does the infracolic compartment contain?

Answer 27

The small and large intestines

Question 28

What is the duodenojejunal flexure?

Answer 28

The bend at the junction of the duodenum and the jejunum

Question 29

What is the main function of the duodenum?

Answer 29

Digestion

Question 30

What is the main function of the jejunum?

Answer 30

Both digestion and absorption

Question 31

What is the main function of the ileum?

Answer 31

Absorption

Question 32

What is the epithelium in the jejunum and ileum?

Answer 32

Simple columnar

Question 33

What is a submucous plexus?

Answer 33

Nerve that causes contraction of local muscle

Question 34

What is a myenteric plexus?

Answer 34

A nerve plexus located in the muscular layer of the intestines

Question 35

What are the finger-like processes found in the small intestine?

Answer 35

Villi

Question 36

What are the transverse folds found in the small intestine?

Answer 36

Plicae circulares

Question 37

What are Peyer's patches?

Answer 37

- A collection of inflammatory cells - Areas of specialised tissue in the lower area of the small intestine that work to distinguish friend from foe as food passes through the GIT - Sensitised cells inside these areas identify antigens and decide whether they are harmless, associated with foods that the person is consuming for nutrition, or harmful, and linked with organisms like bacteria that could try to colonise the body - The Peyer's patches pass the word to the rest of the GIT, facilitating either digestion and uptake of nutrients or an immune system attack on an invader

Question 38

What is an enterocyte?

Answer 38

A cell of the intestinal lining

Question 39

What are examples of enterocytes found in the intestinal lining of the small intestine?

Answer 39

- Microvilli (brush border) - Brush border enzymes (digestion) - Carrier proteins (absorption)

Question 40

What is segmentation (intestinal motility)?

Answer 40

- Contraction to make big things into smaller things

Question 41

What is the function of circular muscle in intestinal motility?

Answer 41

Localised breakdown

Question 42

What is the function of longitudinal muscle in intestinal motility?

Answer 42

Moves the chyme along the length of the tube

Question 43

What is the ileo-caecal junction?

Answer 43

- The point along the course of the GIT where the small intestine (ileum) ends as it opens into the caecal portion of the large intestine; occurs usually within the iliac fossa

Question 44

What can malabsorption syndromes lead to?

Answer 44

Deficiencies that affect the blood e.g. anaemia (iron deficiency) - This can therefore affect the oral mucosa as anaemia can cause gingivitis

Question 45

What are examples of diseases that can effect the intestines?

Answer 45

- Coeliac disease - Chron's disease - Cystic fibrosis

Question 46

What is Meckel's diverticulum?

Answer 46

- Out pouching of the small intestine

Question 47

What is the rule of 2's for Meckel's diverticulum?

Answer 47

- Present after the age of 2 - Roughly 2 inches long - Affects roughly 2% of the population - Lies about 2 feet from the ileo-caecal valve

Question 48

What are the out pouches of Meckel's diverticulum in the small intestine usually made of?

Answer 48

- Mostly ileal mucosa | - May contain acid producing gastric, pancreatic or colonic type mucosa which could be problematic