Motility and Secrection

Question 1

Why is motility in the GI tract important? (4)

Answer 1

1. Propel ingesta along tract
2. Retain ingesta
3. Physical break down
4. Circulate ingesta

Question 2

Motility can be… by nature? (4)

Answer 2

propulsive, retentive, breaking down or mixing

Question 3

What is the first act of digestion?

Answer 3

Mastication (chewing)

Question 4

What type of breakdown is mastication?

Answer 4

Mechanical breakdown

Question 5

The reflex response stimulates what secretions? (4)

Answer 5

• Saliva
• Gastric juices
• Pancreatic juices
• Bile

Question 6

What 2 body parts work in conjunction to stop food from entering the windpipe?

Answer 6

The Soft Palette and the Epiglottis

Question 7

What is the name of the tract that food travel down to the stomach?

Answer 7

The Esophagus

Question 8

What are the main functions of the proximal stomach? (2)

Answer 8

Storage of food and mixing

Question 9

What is the function of the Pylorus

Answer 9

Constricts and lets through only the smallest particles of food.

Question 10

What roles do reflexes play in Gastric Emptying?

Answer 10

Reflexes control gastric emptying by regulating stomach motility

Question 11

Are there different rates of emptying for solid and liquid diets?

Answer 11

Yes! :)

Question 12

What needs to match the rate of food leaving the stomach? (2)

Answer 12

The rate of absorption and digestion in the Small Intestine

Question 13

How many phases are there in Small Intestine motility?

Answer 13

Two

1) During the Postprandial period
2) During the Inter-digestive period

Question 14

In the Digestive phase what are the 2 primary motility patterns?

Answer 14

• Propulsive

* Nonpropulsive or segmentation

Question 15

What is the Propulsive motility pattern?

Answer 15

Peristaltic contractions that move down gut in phase with

slow waves.

Question 16

What is the Nonpropulsive or segmentation motility pattern?

Answer 16

Mixes digesta with digestive juices & moves digesta over

absorptive mucosal surfaces.

Question 17

What does Ruminant mean?

Answer 17

direct translation: Chew the Cud

Question 18

The Rumen content can take up to… of total live weight?

Answer 18

up to 14%

Question 19

Types of Rumen/Reticulum Contractions? (3)

Answer 19

Primary contractions
Secondary contractions
Rumination contractions

Question 20

Where does the primary contractions of the Rumen occur? how often does it happen?

Answer 20

Starts in reticulum, 1-3 per min

Question 21

What does the Primary Rumen contractions achieve?

Answer 21

Mixing of content

Question 22

What does the Secondary Rumen contractions achieve?

Answer 22

Eructation of gas

Question 23

How many steps are there in Rumination? (3)

Answer 23

1) Regurgitate
2) Remasticate
3) Reswallow

Question 24

What 4 secretions are added during Rumination?

Answer 24

Saliva
Gastric
Mucus
Pancreatic

Question 25

How many types of salivary secretion are there? what are they?

Answer 25

2 types

1. Serous (thin and watery)
2. Viscous (mucus-rich)

Question 26

What makes up the majority of saliva?

Answer 26

water makes up 98% of saliva

Question 27

Outside of water what else is in saliva?

Answer 27

Mucin
Amylase
Bicarbonate
Lysozyme and antibodies
Urea

Question 28

What produces Gastric Mucus?

Answer 28

crypt & surface epithelial cells

Question 29

What is contained in Gastric Mucus?

Answer 29

• Glycoproteins

* Small amounts of mucopolysaccharides

Question 30

What are the main types of pancreatic enzymes? (3)

Answer 30

• Proteolytic enzymes
• Pancreatic amylase & chitinase
• Pancreatic lipase