Cuestionario: Digestive System Anatomy — 38 preguntas

1. What is the approximate length and overall form of the digestive system?

A. A solid organ extending from the pharynx to the rectum and measuring about 3 meters

B. A series of sacs extending from the stomach to the anus and measuring about 15 meters

C. A tube extending from the mouth to the anus and measuring about 9 meters

D. A branching network extending from the mouth to the liver and measuring about 9 meters

Answer: (C)

Explicación

The digestive system is a continuous tube that runs from the mouth to the anus and is approximately 9 meters long.

2. Which sequence correctly lists the major regions of the digestive tract from the mouth onward?

A. Mouth, gallbladder, esophagus, stomach, liver, large intestine

B. Oral cavity, pharynx, esophagus, stomach, small intestine, large intestine

C. Oral cavity, larynx, trachea, stomach, large intestine, small intestine

D. Pharynx, oral cavity, esophagus, pancreas, small intestine, rectum

Answer: (B)

Explicación

The digestive tract consists of the oral cavity, pharynx, esophagus, stomach, small intestine, and large intestine in that order.

3. Which epithelial pairing correctly distinguishes the upper and lower digestive tracts?

A. Columnar epithelium in the upper tract and stratified squamous epithelium in the lower tract

B. Stratified squamous epithelium in the upper tract and columnar epithelium in the lower tract

C. Stratified cuboidal epithelium in the upper tract and transitional epithelium in the lower tract

D. Transitional epithelium in the upper tract and stratified cuboidal epithelium in the lower tract

Answer: (B)

Explicación

The upper digestive tract is mainly protected by tough stratified squamous epithelium, whereas the lower tract is mainly lined by delicate glandular columnar epithelium.

4. How is the oral cavity organized anatomically?

A. It extends from the cheeks to the esophagus and consists of the pharynx and larynx

B. It extends from the lips to the pharynx and consists of the oral vestibule and proper oral cavity

C. It extends from the teeth to the stomach and consists of the hard palate and soft palate

D. It extends from the nose to the larynx and consists of the nasal vestibule and oropharynx

Answer: (B)

Explicación

The oral cavity is the initial part of the digestive system, extending from the lips to the pharynx and divided into the oral vestibule and proper oral cavity.

5. Which description best identifies the oral vestibule?

A. A central space inside the dental arches bounded by the tongue and pharynx

B. A horseshoe-shaped space outside the dental arches bounded by the lips and cheeks

C. A bony chamber above the nasal cavity bounded by the hard and soft palate

D. A vertical passage behind the pharynx bounded by the tongue and epiglottis

Answer: (B)

Explicación

The oral vestibule lies outside the dental arches, has a horseshoe shape, and is bounded externally by the lips and cheeks.

6. Which statement correctly compares the hard and soft palates?

A. The hard palate forms the anterior two-thirds of the roof, while the soft palate forms the posterior one-third

B. The hard palate forms the entire roof, while the soft palate forms the floor of the mouth

C. The hard palate lies behind the pharynx, while the soft palate lies in front of the teeth

D. The hard palate forms the posterior one-third of the roof, while the soft palate forms the anterior two-thirds

Answer: (A)

Explicación

The hard palate is the anterior two-thirds of the oral roof, whereas the soft palate is the posterior one-third. The hard palate is bony, while the soft palate is musculoconnective.

7. During swallowing, what is the main effect of elevating and tensing the soft palate?

A. It closes the upper nasopharynx and helps prevent food from entering it

B. It opens the upper nasopharynx and directs food into the nasal cavity

C. It opens the pharyngeal isthmus and directs food into the mouth

D. It closes the oral vestibule and prevents food from reaching the teeth

Answer: (A)

Explicación

The levator and tensor veli palatini elevate and tense the soft palate during swallowing, closing the upper nasopharynx to keep food out of it.

8. Which arrangement correctly describes the three main parts of a tooth?

A. A crown embedded in an alveolus, a widened neck, and a free root projecting into the oral cavity

B. A root projecting into the oral cavity, a broad neck, and a crown embedded in an alveolus

C. A neck embedded in an alveolus, a free root, and a crown enclosed within the gum

D. A root embedded in an alveolus, a narrowed neck, and a free crown projecting into the oral cavity

Answer: (D)

Explicación

Each tooth has a root embedded in an alveolus, a narrowed neck, and a free crown that projects into the oral cavity.

9. How many deciduous and permanent teeth do humans typically develop?

A. 20 deciduous teeth and 32 permanent teeth

B. 16 deciduous teeth and 28 permanent teeth

C. 24 deciduous teeth and 36 permanent teeth

D. 32 deciduous teeth and 20 permanent teeth

Answer: (A)

Explicación

Humans first develop 20 deciduous teeth and later have 32 permanent teeth.

10. Which set contains the four groups of permanent human teeth?

A. Incisors, canines, premolars, and molars

B. Canines, deciduous teeth, premolars, and alveoli

C. Incisors, cusps, bicuspids, and third molars

D. Molars, roots, crowns, and incisors

Answer: (A)

Explicación

The four groups of permanent teeth are incisors, canines, premolars, and molars.

11. What is the formula for one half of the permanent dentition?

A. I2 C1 M2 over I2 C1 M2

B. I1 C1 P2 M3 over I1 C1 P2 M3

C. I3 C1 P2 M2 over I3 C1 P2 M2

D. I2 C1 P2 M3 over I2 C1 P2 M3

Answer: (D)

Explicación

The permanent dentition formula for one half of the mouth is I2 C1 P2 M3 in both the upper and lower jaws.

12. Which combination best describes the functions of the tongue?

A. Air filtration, hearing, balance, and smell

B. Speech, chewing, swallowing, and taste sensation

C. Jaw movement, breathing, circulation, and vision

D. Hormone secretion, digestion, and blood filtration

Answer: (B)

Explicación

The tongue is a highly mobile muscular organ involved in speech, chewing, swallowing, and taste sensation.

13. Which set lists all four types of lingual papillae?

A. Circumvallate, palatine, foliate, and sublingual

B. Palatine, pharyngeal, tubal, and lingual

C. Filiform, fungiform, foliate, and vallate

D. Fungiform, molar, conical, and pharyngeal

Answer: (C)

Explicación

The four types of lingual papillae are filiform, fungiform, foliate, and vallate papillae.

14. A papilla provides friction for manipulating food but does not contribute directly to taste. Which type is it most likely to be?

A. Foliate papilla

B. Fungiform papilla

C. Vallate papilla

D. Filiform papilla

Answer: (D)

Explicación

Filiform papillae lack taste buds and have a mechanical function. Fungiform, foliate, and vallate papillae contain taste buds.

15. Which statement correctly distinguishes the extrinsic and intrinsic muscles of the tongue?

A. Extrinsic muscles change tongue position, whereas intrinsic muscles change tongue shape.

B. Extrinsic muscles change tongue shape, whereas intrinsic muscles elevate the pharynx.

C. Extrinsic muscles produce taste, whereas intrinsic muscles produce saliva.

D. Extrinsic muscles constrict the pharynx, whereas intrinsic muscles open the larynx.

Answer: (A)

Explicación

The extrinsic tongue muscles alter the tongue’s position, while the intrinsic muscles alter its shape. Both groups are innervated by the hypoglossal nerve.

16. What is the primary functional description of the pharynx?

A. A digestive gland that secretes enzymes into the oral cavity

B. A shared passage for food and air that also acts as a speech resonator

C. A respiratory chamber responsible for exchanging gases

D. A muscular valve that separates the stomach from the esophagus

Answer: (B)

Explicación

The pharynx is a shared digestive and respiratory organ that conveys food and air and contributes to speech resonance.

17. Which sequence correctly lists the three parts of the pharynx from superior to inferior?

A. Oropharynx, nasopharynx, laryngopharynx

B. Laryngopharynx, oropharynx, nasopharynx

C. Nasopharynx, laryngopharynx, oropharynx

D. Nasopharynx, oropharynx, laryngopharynx

Answer: (D)

Explicación

The pharynx consists of the nasopharynx, oropharynx, and laryngopharynx in superior-to-inferior order.

18. During swallowing, which pharyngeal muscle group narrows the lumen to help propel material downward?

A. The muscles of the soft palate

B. The three pharyngeal constrictors

C. The stylopharyngeus, palatopharyngeus, and salpingopharyngeus

D. The intrinsic muscles of the tongue

Answer: (B)

Explicación

The three pharyngeal constrictors narrow the pharyngeal lumen during swallowing. The longitudinal muscles instead elevate the pharynx.

19. A structure at the entrance to the pharynx contains lingual, palatine, tubal, and pharyngeal tonsils. What is this structure called?

A. The pharyngeal constrictor system

B. The terminal sulcus

C. The laryngopharyngeal passage

D. Waldeyer’s lymphatic ring

Answer: (D)

Explicación

Waldeyer’s lymphatic ring is formed by the lingual, palatine, tubal, and pharyngeal tonsils and helps protect the body at the pharyngeal entrance.

20. What is the primary function of the esophagus?

A. To absorb most nutrients from digested food

B. To convey swallowed material from the pharynx to the stomach

C. To secrete bile into the digestive tract

D. To exchange gases between air and blood

Answer: (B)

Explicación

The esophagus is an approximately 25 cm hollow tube extending from the sixth cervical to the tenth or eleventh thoracic vertebra and conveying swallowed material to the stomach.

21. Which description best characterizes the shape and major landmarks of the stomach?

A. A flattened chamber with a cecum and an appendix

B. A spherical gland with a cervix and an ileum

C. A variable J-shaped sac with a cardia and a pylorus

D. A straight cylindrical tube with a fundus and a larynx

Answer: (C)

Explicación

The stomach is a variable, expanded sac-like organ shaped approximately like a vertical hook or the letter J, and it has a cardia and a pylorus.

22. Which statement correctly describes the stomach’s regions and curvatures?

A. It includes the body, fundus, and pyloric part; the lesser curvature is concave and the greater curvature is convex.

B. It includes the fundus, jejunum, and pyloric antrum; both curvatures are convex.

C. It includes the cardia, ileum, and duodenum; the lesser curvature is convex and the greater curvature is concave.

D. It includes the body, cecum, and pyloric canal; both curvatures are concave.

Answer: (A)

Explicación

The stomach consists of the body, fundus, and pyloric part, including the pyloric antrum and canal. Its lesser curvature is concave, while its greater curvature is convex.

23. Which sequence correctly lists the three parts of the small intestine from proximal to distal?

A. Ileum, duodenum, and jejunum

B. Duodenum, jejunum, and ileum

C. Jejunum, ileum, and duodenum

D. Duodenum, ileum, and jejunum

Answer: (B)

Explicación

The small intestine is divided into the duodenum, jejunum, and ileum in that order.

24. Which description best characterizes the duodenum?

A. A 1.5-m segment divided into ascending and descending parts

B. A 6-m mobile segment extending from the cecum to the rectum

C. A 25-cm C-shaped segment surrounding the head of the pancreas

D. A spherical chamber located entirely within the left hypochondrium

Answer: (C)

Explicación

The duodenum is approximately 25 cm long, C-shaped, and surrounds the head of the pancreas.

25. What forms the hepatopancreatic ampulla?

A. The division of the duodenum into four parts

B. The junction of the hepatic artery and portal vein

C. The union of the common bile duct and major pancreatic duct

D. The union of the ileum and ascending colon

Answer: (C)

Explicación

The hepatopancreatic ampulla is formed where the common bile duct joins the major pancreatic duct. It opens into the duodenum at the major duodenal papilla.

26. Which feature is particularly characteristic of the ileum and contributes to the small intestine’s absorptive and immune functions?

A. Peyer’s patches and expanded mucosal surface from folds and villi

B. A vermiform appendix and an ileal valve

C. Haustral sacculations and a concentration of anal sphincters

D. Four colonic segments and extensive mesenteries

Answer: (A)

Explicación

Circular folds and villi greatly increase mucosal surface area, while aggregated lymphoid nodules called Peyer’s patches are characteristic of the ileum.

27. What is the approximate length and extent of the large intestine?

A. 9 cm, from the cecum to the McBurney point

B. 1.5–1.8 m, from the ileal opening to the anus

C. 4.6–9 m, from the pylorus to the ileal opening

D. 25 cm, from the pylorus to the jejunum

Answer: (B)

Explicación

The large intestine is the terminal part of the digestive tract and measures approximately 1.5–1.8 m from the ileal opening to the anus.

28. Which structures comprise the large intestine?

A. Cecum with vermiform appendix, colon, and rectum

B. Esophagus, stomach, and duodenum

C. Liver, gallbladder, and pancreas

D. Duodenum, jejunum, and ileum

Answer: (A)

Explicación

The large intestine consists of the cecum with its vermiform appendix, the colon, and the rectum.

29. Which pair of colonic segments is mobile because each has a mesentery?

A. Ascending and descending colons

B. Descending and sigmoid colons

C. Ascending and transverse colons

D. Transverse and sigmoid colons

Answer: (D)

Explicación

The transverse and sigmoid colons have mesenteries and are therefore mobile, whereas the ascending and descending colons are attached to the posterior abdominal wall.

30. During defecation, which muscle arrangement is correct?

A. Both anal sphincters are smooth muscle controlled involuntarily

B. Both anal sphincters are striated muscle controlled voluntarily

C. The internal anal sphincter is striated muscle, and the external anal sphincter is involuntary smooth muscle

D. The internal anal sphincter is smooth muscle, and the external anal sphincter is voluntarily controlled striated muscle

Answer: (D)

Explicación

The internal anal sphincter is smooth muscle, while the external anal sphincter is striated muscle under voluntary control.

31. What is a major digestive function of the liver?

A. Producing bile and processing blood from the digestive tract

B. Storing feces and regulating defecation

C. Producing pancreatic enzymes and receiving lymph from the ileum

D. Absorbing most nutrients through intestinal villi

Answer: (A)

Explicación

The liver is the largest digestive gland; it produces bile and processes blood containing substances absorbed from the digestive tract.

32. Which statement about the liver’s lobes is correct?

A. It has ascending, transverse, descending, and sigmoid lobes, with the left lobe largest

B. It has only right and left lobes, which are approximately equal in size

C. It has quadrate and caudate lobes but lacks right and left lobes

D. It has right, left, quadrate, and caudate lobes, with the right lobe considerably larger than the left

Answer: (D)

Explicación

The liver has right, left, quadrate, and caudate lobes, and the right lobe is considerably larger than the left.

33. Which description correctly defines a hepatic lobule?

A. A circular duct formed by the union of the bile and pancreatic ducts

B. A mobile lobe attached to the liver by a mesentery

C. A hexagonal unit of hepatocyte plates radiating around a central vein

D. A muscular unit surrounding the terminal opening of the digestive tract

Answer: (C)

Explicación

A hepatic lobule is a hexagonal structural unit in which plates of hepatocytes radiate around a central vein, with capillaries carrying blood toward it.

34. Which pairing correctly describes the liver’s two main blood supplies?

A. Hepatic artery—functional circulation from the spleen; portal vein—nutritive circulation

B. Hepatic artery—bile drainage; portal vein—lymphatic drainage

C. Hepatic artery—blood drainage from the liver; portal vein—oxygen delivery to hepatocytes

D. Hepatic artery—nutritive circulation; portal vein—functional circulation from digestive organs and spleen

Answer: (D)

Explicación

The hepatic artery supplies nutritive blood, while the portal vein brings blood from the digestive organs and spleen as the functional circulation.

35. Which anatomical description correctly identifies the pancreas?

A. Its head lies near the splenic hilum, its body extends downward, and its tail reaches the duodenum

B. Its head lies in the concavity of the duodenum, its body extends leftward, and its tail reaches the splenic hilum

C. Its head lies beside the kidney, its body extends rightward, and its tail reaches the major duodenal papilla

D. Its head lies within the liver, its body surrounds the gallbladder, and its tail reaches the jejunum

Answer: (B)

Explicación

The pancreas has a head situated in the duodenal concavity, a body extending toward the left, and a tail reaching the splenic hilum.

36. How does the exocrine pancreas differ from the endocrine pancreas?

A. The exocrine pancreas secretes digestive enzymes through a duct, whereas the endocrine pancreas secretes hormones from islets

B. The exocrine pancreas stores bile, whereas the endocrine pancreas produces bile acids

C. The exocrine pancreas secretes hormones into blood, whereas the endocrine pancreas secretes enzymes through a duct

D. The exocrine pancreas regulates blood glucose directly, whereas the endocrine pancreas forms the duodenal wall

Answer: (A)

Explicación

Exocrine pancreatic acini release digestive enzymes through ducts, while endocrine islets of Langerhans release hormones. The distinction is based on both the secretion and its route of release.

37. Which hormones are secreted by pancreatic endocrine cells to help regulate blood glucose concentration?

A. Bile salts and bilirubin

B. Insulin and glucagon

C. Amylase and lipase

D. Pepsin and gastrin

Answer: (B)

Explicación

Pancreatic endocrine cells secrete insulin and glucagon, which are essential for regulating blood glucose concentration.

38. Which sequence correctly describes the formation and course of the common bile duct?

A. The right and left hepatic ducts unite as the common hepatic duct, which joins the cystic duct before opening at the major duodenal papilla

B. The common hepatic duct divides into the right and left cystic ducts, which open into the jejunum

C. The right and left hepatic ducts unite with the pancreatic duct to form the cystic duct, which opens into the ileum

D. The cystic duct joins the right hepatic duct, which opens directly into the stomach through the pylorus

Answer: (A)

Explicación

The right and left hepatic ducts form the common hepatic duct; this joins the cystic duct to form the common bile duct, which opens at the major duodenal papilla.