Alimentary System – Comprehensive Review

A comprehensive set of question-and-answer flashcards covering definitions, anatomy, relations, blood supply, innervation, and clinical correlations for the entire alimentary system as presented in the lecture notes.

What does the term “ampulla” refer to in anatomy?

A cavity or the dilated end of a duct.

Define the anatomical word root “gastro–”.

Relating to the stomach.

Define the anatomical word root “hepato–”.

Relating to the liver.

What is the vestibule of the oral cavity?

The space between the teeth and the cheeks/lips.

How many incisors are found in one quadrant of adult dentition?

Two incisors.

Name the roof structures of the oral cavity.

Hard palate and soft palate.

Which bones form the hard palate?

Palatine process of the maxilla and horizontal plate of the palatine bone.

What soft-tissue projection hangs from the posterior edge of the soft palate?

The uvula.

List the five muscles of the soft palate.

Tensor veli palatini, Levator veli palatini, Palatoglossus, Palatopharyngeus, Musculus uvulae.

Which muscle forms the oral diaphragm?

Mylohyoid muscle.

Name the three paired major salivary glands.

Parotid, submandibular, and sublingual glands.

Through which duct does the parotid gland empty?

Stensen’s (parotid) duct.

Which salivary duct is most prone to calculi formation?

Wharton’s duct of the submandibular gland.

What secretion predominates from the sublingual gland?

Mucous secretion.

What surface of the tongue is called its dorsum?

The free upper surface.

Name the V-shaped groove that separates the anterior two-thirds and posterior one-third of the tongue.

Sulcus terminalis.

Which papillae of the tongue contain no taste buds?

Filiform papillae.

Which cranial nerve supplies general sensation to the anterior two-thirds of the tongue?

Lingual nerve (branch of CN V3).

Which cranial nerve carries taste from the anterior two-thirds of the tongue?

Chorda tympani branch of the facial nerve (CN VII).

What is the principal artery to the tongue?

Lingual artery (branch of the external carotid).

List the four extrinsic muscles of the tongue.

Genioglossus, Hyoglossus, Styloglossus, Palatoglossus.

Which tongue muscle protrudes the tongue?

Genioglossus.

Which tongue muscle is NOT supplied by the hypoglossal nerve?

Palatoglossus (supplied by pharyngeal plexus from vagus/accessory).

What is the average adult capacity of the stomach?

1 000–1 500 mL.

Name the four main regions of the stomach.

Cardia, fundus, body, pylorus.

At which vertebral level is the cardiac orifice of the stomach located?

Opposite T11 vertebra.

Which arteries form the arterial circle along the lesser curvature of the stomach?

Left gastric and right gastric arteries.

Which arteries form the arterial arcade along the greater curvature of the stomach?

Left and right gastro-epiploic (gastroomental) arteries.

Into which lymph-node group do all gastric lymphatics eventually drain?

Celiac group of lymph nodes.

What is the main sympathetic spinal cord level supplying the stomach?

T6–T9.

State the ‘Rule of 2 s’ volume for the stomach.

Approximately 2 pints (~1 L).

Which gastric cells secrete hydrochloric acid?

Oxyntic (parietal) cells.

Which part of the small intestine is retroperitoneal and largely immobile?

Duodenum (except its first 5 cm).

Name the four parts of the duodenum in order.

Superior (1st), descending (2nd), horizontal (3rd), ascending (4th).

Which arteries form the arterial arcade around the head of the pancreas and second part of the duodenum?

Superior and inferior pancreatico-duodenal arteries.

What is the length ratio of jejunum to ileum in the small intestine?

Proximal 2/5 jejunum, distal 3/5 ileum.

Which part of the small intestine has more prominent plicae circulares and thicker walls?

Jejunum.

Presence of Peyer’s patches is characteristic of which intestinal segment?

Ileum.

What congenital anomaly represents a remnant of the vitelline duct?

Meckel’s (ileal) diverticulum.

Name the three bands of longitudinal muscle on the large intestine.

Taeniae coli.

What fatty peritoneal tags hang from the colon?

Appendices epiploicae.

Which structure marks the beginning of the large intestine?

Caecum.

Where is the McBurney’s point located?

At the junction of lateral one-third and medial two-thirds of a line from the umbilicus to the right ASIS (surface projection of appendix).

Which artery is the sole blood supply to the appendix?

Appendicular artery (branch of inferior division of ileocolic).

Which sympathetic spinal level refers pain from appendicitis to the umbilicus?

T10.

Which colon segment is intraperitoneal and suspended by the transverse mesocolon?

Transverse colon.

What ligament supports the left colic flexure?

Phrenico-colic ligament.

Which artery primarily supplies the descending colon?

Left colic artery (branch of inferior mesenteric).

Name the peritoneal fold that suspends the sigmoid colon.

Sigmoid mesocolon.

At what vertebral level does the recto-sigmoid junction occur?

In front of the third sacral vertebra (S3).

Which three permanent transverse mucosal folds are found in the rectum?

Houston’s valves (transverse rectal folds).

What is the principal arterial supply to the rectum?

Superior rectal artery.

Which veins create a porto-systemic anastomosis around the rectum?

Superior rectal (portal) with middle & inferior rectal (systemic) veins.

Into which lymph nodes does the lower anal canal drain?

Superficial inguinal lymph nodes.

Name the involuntary sphincter of the anal canal.

Internal anal sphincter.

Which nerve supplies the external anal sphincter?

Inferior rectal branch of the pudendal nerve (plus perineal branch of S4).

What marks the mucocutaneous junction inside the anal canal?

Pectinate (dentate) line.

Which gland is both exocrine and endocrine and lies retroperitoneally across the posterior abdominal wall?

Pancreas.

Into which part of the duodenum does the ampulla of Vater open?

Second (descending) part of the duodenum.

What is the largest gland in the human body?

The liver.

Which ligament separates the right and left anatomical lobes of the liver?

Falciform ligament on the diaphragmatic surface.

What structures make up the portal triad at the porta hepatis?

Hepatic artery, portal vein, and bile duct (plus lymphatics and nerves).

Name the macrophage-type phagocytic cells lining hepatic sinusoids.

Kupffer cells.

List the main components of bile.

Bile salts, bilirubin, cholesterol, phospholipids, and electrolytes.

What is the function of the gall bladder?

Stores and concentrates bile (up to 10-fold) until needed for fat digestion.

Which muscle elevates the tongue and pulls it backward?

Styloglossus.

What structure forms the lower esophageal sphincter?

Intrinsic circular smooth muscle of the distal esophagus (physiological, not anatomical).

At what distances from the upper incisors are the three esophageal constrictions located?

15 cm (cricopharyngeal), 23 cm (aortic/bronchial), 40 cm (diaphragmatic).

Which artery is the principal supply to the cervical esophagus?

Inferior thyroid artery.

Which nerve plexus provides parasympathetic innervation to most of the GI tract up to the proximal 2/3 of the transverse colon?

Vagus nerve via enteric (myenteric and submucosal) plexuses.

What are rugae?

Longitudinal folds of gastric mucosa visible when the stomach is empty or partially filled.

Which layer of stomach muscle is unique compared with the rest of the GI tract?

Inner oblique muscle layer.

What hormone is secreted by pyloric G-cells?

Gastrin.

Which ligament contains the short gastric arteries?

Gastro-splenic ligament.

Which nerve branch along the lesser curvature is sometimes cut to reduce acid secretion (highly selective vagotomy)?

Nerve of Latarjet (anterior gastric branch of the vagus).

Name two substances significantly absorbed in the stomach.

Water and alcohol (also limited glucose).

What are the main functions of the large intestine?

Absorption of water, vitamin synthesis via bacterial flora, and storage of feces.

Which structure prevents backflow at the ileocecal junction?

Ileocecal valve.

Which colon segment shows the narrowest lumen and is often the site of volvulus?

Sigmoid colon.

Which peritoneal pouch between the rectum and bladder is lowest in males?

Recto-vesical pouch.

Which peritoneal pouch between rectum and uterus is lowest in females?

Recto-uterine pouch (pouch of Douglas).

What is the surgical significance of the bare area of the stomach’s posterior surface?

It allows direct adhesion or spread of infection to adjacent organs without peritoneal barrier.

Which nerve is closely related to the posterior surface of the esophagus in the abdomen?

Right vagus nerve (becomes posterior gastric nerve).

Which artery supplies the proximal 5 cm (duodenal cap) of the duodenum?

Superior pancreatico-duodenal artery (branch of gastroduodenal).

Name three differences between jejunal and ileal mesentery fat content.

Jejunum: fat near root only; Ileum: fat throughout mesentery; jejunal mesentery appears more translucent ‘windows’.

Which lymph node chain receives lymph from the appendix?

Superior mesenteric (via ileocolic) nodes.

Which structure marks the meeting point of all three taeniae coli?

Base of the appendix.

What is the average length of the vermiform appendix?

About 9 cm (range 2–20 cm).

Which positional type of appendix is most common?

Retrocecal (12 o’clock).

Which artery anastomoses along the colon’s inner margin forming a collateral channel?

Marginal artery of Drummond.

Name the three main arterial supplies to the rectum and anal canal.

Superior, middle, and inferior rectal arteries.

Which embryologic structures give rise to (a) upper anal canal and (b) lower anal canal?

(a) Endoderm of hindgut (cloaca); (b) Ectoderm of proctodeum.

Where is bile released into the GI tract?

Into the second part of the duodenum via the hepatopancreatic ampulla (ampulla of Vater).

Which ligament carries the portal triad to the liver?

Hepatoduodenal ligament (part of the lesser omentum).

Which liver lobe lies between the fissure for ligamentum venosum and the inferior vena cava?

Caudate lobe.

State two endocrine hormones released by the pancreas.

Insulin and glucagon (also somatostatin, pancreatic polypeptide).

What is the function of bile salts?

Emulsify fats to aid lipid digestion and absorption.

Which region of the abdomen does the jejunum mainly occupy?

Umbilical (left upper) region.

Which sympathetic nerves reduce motility and secretion of jejunum/ileum?

Greater and lesser splanchnic nerves (via superior mesenteric plexus).

What muscular sling maintains the anorectal angle?

Puborectalis part of levator ani muscle.