Lesson 1- Introduction to digestive system

Question 1

Anus

Answer 1

A sphincter involved in the defecation reflex

Question 2

Appendix

Answer 2

A projection of the cecum at the entrance of the large intestine; may have a role in immune function in humans

Question 3

Cardiac sphincter

Answer 3

A ring of muscle located at the entrance of the stomach; keeps digested food (acid chime) in the stomach, preventing reflux during mechanical digestion to the stomach

Question 4

Duodenum

Answer 4

The first section of the mall intestine; important for digestion and absorption of nutrients; makes enzymes (ex. maltase and peptidase); receives enzymes and bicarbonate (to neutralize acid) from the pancreas; receives bile from the liver via the gallbladder that emulsifies fats; absorption of nutrients facilitated by numerous villi

Question 5

Epiglottis

Answer 5

Meets with the glottis during swallowing; covers the opening to the trachea and sends food into the esophagus

Question 6

Esophagus (food tube)

Answer 6

About 25 cm long; moves the food bolus to the stomach by a series of coordinated smooth muscle contractions (peristalsis)

Question 7

Gall bladder

Answer 7

Stores bile for the emulsification of fats/ lipids

Question 8

Large intestine (colon)

Answer 8

Important for the absorption of water, production of vitamins, and storage of indigestible materials, such as plant fibre (cellulose)

Question 9

Liver

Answer 9

Produces bile that is stored in the gall bladder and emulsifies fat in the small intestine

Question 10

Mouth

Answer 10

Responsible for the mechanical and chemical digestion of food. In the mouth food is mixed with saliva forming a food ball or bolus

Question 11

Pancreas

Answer 11

Makes pancreatic juice that contains numerous digestive enzymes and bicarbonate ions that neutralize acid chyme entering the small intestine

Question 12

Pharynx (throat)

Answer 12

A common passage for the food bolus to the esophagus and air to the trachea; swallowing is the process that occurs in the pharynx

Question 13

Pyloric sphyncter

Answer 13

Small piece of smooth visceral muscle at the base of the stomach that controls the amount of acid chyme that enters the duodenum by releasing small quantities at regular intervals

Question 14

Rectum

Answer 14

Functions in the storage of feces and defecation

Question 15

Salivary glands

Answer 15

Produce about a litre of saliva each day; saliva contains salivary amylase, which begins the hydrolysis of starch into maltose

Question 16

Small intestine

Answer 16

First portion of the intestine consisting of the duodenum, jejunum and ileum. Location of final digestion of food and major uptake of nutrients. Essential in the chemical digestion and absorption of nutrients, arguably the most important digestive organ; the site of action for pancreatic juice, intestinal juice, and bile; responsible for the absorption of nutrients into the blood and lymph (tissue fluid) for use in the body

Question 17

Stomach

Answer 17

A muscular organ that mechanically and chemically digests food; produces hydrochloric acid that lowers the pH in the stomach; low pH activates the pepsinogen enzyme, which digests proteins and peptides

Question 18

Teeth

Answer 18

Cut and crush food increasing the food’s surface area and mixing it with saliva

Question 19

Tongue

Answer 19

Involved in taste; as well as moving, mixing, and positioning food for chewing and swallowing