Question

fill in the blanks.
word bank
bolus villi intestine
break down 30 absorb peristalsis

1. the human g.i. tract is about ______ feet long.
2. the main function of the digestive system is to ______ food into nutrients that are more easily absorbed into the bloodstream to be used by cells.
3. the g.i. tract has a lot of surface area so that it can ______ a lot of nutrients.
4. the enormous surface area is mostly caused by folds, ______, and microvilli that cover the walls of the small intestine.
5. a ______ is a mass of food that travels through your g.i. tract.
6. ______ are the wavelike muscle contractions that move the bolus through the g.i. tract.
7. the liver and pancreas secrete digestive juices into the small ______.

Explanation:

1. The human gastrointestinal (G.I.) tract is approximately 30 feet long.
2. The digestive system's main role is to break down food into nutrients for absorption into the bloodstream.
3. The G.I. tract's large surface - area allows it to absorb a lot of nutrients.
4. The large surface - area of the small intestine is due to folds, villi, and microvilli.
5. A bolus is a mass of food moving through the G.I. tract.
6. Peristalsis are the wave - like muscle contractions that move the bolus through the G.I. tract.
7. The liver and pancreas secrete digestive juices into the small intestine.

Answer:

1. 30
2. break down
3. absorb
4. villi
5. bolus
6. Peristalsis
7. intestine