intro to digestive system

Question 1

Define digestion

Answer 1

The process of breaking down food into molecules small enough to be absorbed into the circulatory system for transport through the body.

Question 2

What are the two types of Digestions?

Answer 2

1. Mechanical digestion
2. Chemical digestion

Question 3

Mechanical digestion

Answer 3

breaks down food through chewing and movement of the tongue, and the grinding action of the stomach.

Question 4

Where does mechanical digestion take place?

Answer 4

In mouth and stomach

Question 5

Chemical digestion

Answer 5

the use of digestive enzymes to break down large molecules in food to make them small enough to be absorbed into the blood.

Question 6

Where does chemical digestion take place?

Answer 6

A little bit in the mouth and majority takes place in the stomach.

Question 7

What are digestive enzymes?

Answer 7

These are proteins used to catalyze the process of digestion or breaking down food.

Question 8

Digestive enzymes are equivalent to =

Answer 8

Chemicals that help breakdown food.

Question 9

Name the 5 layers of the digestive tract wall?

Answer 9

1. Mucosa
2. Muscularis Mucosae
3. Submucosa
4. Muscularis Externa
5. Serosa

Question 10

(1) Mucosa Layer

Answer 10

-Thin lining on the inside of digestive tract

Question 11

What is the primary function of the layer mucosa?

Answer 11

secretion of mucous to keep the digestive tract moist.

Question 12

What kind of tissue is the Mucosa layer made up of?

Answer 12

-Mostly simple columnar epithelium with deeper
-loose connective tissue (in the lamina proper)

Question 13

(2) Muscularis mucosae Layer

Answer 13

region in the mucosa containing two layers of smooth muscle.

Question 14

In the muscularis mucosae layer, what are the characteristics of the two layers of smooth muscle?

Answer 14

-Inner layer is circular
-Outer layer is Longitudinal.

Question 15

What is the purpose of the two layers of smooth muscle found in the muscularis mucosae in the digestive tract?

Answer 15

The contraction of these two layers of muscle allow for the movement of food inside of the digestive tract.

Question 16

(3) submucosa Layer

Answer 16

-A layer of dense irregular connective tissue beneath the mucosa
-Contains blood vessels, nerves and lymph ducts

Question 17

(4) Muscularis Externa Layer

Answer 17

A region that contains two layers of smooth muscles (circular and longitudinal in shape).

Question 18

What is the purpose of the two smooth muscle layer (circular and longitudinal) in the digestive tract?

Answer 18

The contraction of these muscles allow for the movement of food passing through the digestive tract.

Question 19

What is Peristalsis?

Answer 19

involuntary contraction and relaxation of longitudinal and circular muscles throughout the digestive tract, allowing for movement of food.

Question 20

(5) Serosa layer

Answer 20

-This is the most outer layer or the most superficial layer covering the digestive tract.
-only specific to the digestive tract

Question 21

What organs are said NOT to be covered by the serosa layer? but are otherwise covered by?

Answer 21

1. Pharynx
2. Esophagus
3. Mouth
4. Rectum

These organs are covered by a layer called Adventitia

Question 22

What kind of tissue lines the esophagus?

Answer 22

stratified squamous epithelium

Question 23

The serosa layer of the digestive tract is said to cover above/below the diaphragm?

Answer 23

below diaphragm

Question 24

The adventitia layer is said to cover below or above the diaphragm?

Answer 24

covers organs above the diaphragm. i.e esophagus.