Specialized Digestion and Illness (lesson four)

Question 1

Types of Digestion

Answer 1

• simple
• and complex

Question 2

Simple Digestion

Answer 2

Simple animals, like flatworms and jellyfish, have a simple digestive sac called the gastrovascular cavity
- There is only one opening that serves as both an entrance for food and an exit for waste
- Food is broken down in the cavity by chemicals and is absorbed by the surrounding cells

Question 3

Complex Digestion

Answer 3

More complex animals have a complete digestive system, like humans
- has two openings and a digestive tract organized into specialized regions that enable the breakdown and absorption of food that moves only in one direction
- Some animals can regurgitate but overall, movement is in one direction

Question 4

what are “Accessory” Organs

Answer 4

There are a number of organs that are known as “accessory” organs that function to support the digestive system but are NOT part of the digestive tract.
Accessory organs include:
- Liver
- Pancreas
- Gall Bladder

Question 5

does food pass through the accessory organs?

Answer 5

Food does not pass through these organs. These organs support digestion by secreting substances that are needed for digestion, absorption, and excretion.

Question 6

Pancreas

Answer 6

-The pancreas is a long flat gland found between your stomach and your duodenum

Question 7

what does the pancreas secret?

Answer 7

It both secretes hormones that regulate blood sugar (i.e. insulin) and enzymes that aid in digestion
- Amylase is secreted to help digest starch
- Trypsin is secreted to help digest protein
- Lipases are secreted to help break down lipids

Question 8

liver

Answer 8

The liver is the largest internal organ and performs numerous bodily functions
- The main role in digestion is to release bile to emulsify fats and break them into tiny droplets called micelles to make them easier to digest

Question 9

what else does the Liver fliter

Answer 9

The liver also filters the blood of toxins (like alcohol), stores carbohydrates as glycogen, stores fat-soluble vitamins (A, D, E, & K), and many other important functions

Question 10

Gall Bladder

Answer 10

Bile is continually produced and when it is not needed, it is stored in the gallbladder
- When lipids enter the duodenum, it stimulate the gall bladder to begin contracting (a hormone assists in the process of stimulating these contractions)
- The bile can then be pushed through the cystic duct and released into the duodenum via the common bile duct

Question 11

types of digestive Illness

Answer 11

• Acid Reflux
• Stomach Ulcers
• Endoscopy

Question 12

Acid Reflux

Answer 12

Acid reflux, or heartburn, is caused when the gastroesophageal sphincter does not fully close
- This allows acid from the stomach to enter the esophagus and cause a burning sensation
- This can be triggered by overeating and overfilling the stomach or smoking which relaxes the sphincter and also increases acid production

Question 13

what is Stomach Ulcers

Answer 13

A bacteria, called Helicobacter pylori, can survive in the low pH (highly acidic environment) of the stomach by secreting acid-neutralizing enzymes
- This bacteria also burrows into the mucus layer of the stomach and prevents the production of this mucus (recall: the mucus serves as a protective layer/barrier of the stomach wall)

Question 14

what do stomach ulcers cause

Answer 14

• can cause an open sore to be produced by the acid eating away at the stomach lining, called an ulcer
• Ulcers can bleed and can be quite painful
• They are also very dangerous because if left untreated, H. pylori can then infect the whole body
• H. pylori can usually be treated with antibiotics
• The existence of this bacteria and its connection to ulcers was found when Dr. Barry Marshall consumed the bacteria himself to prove his hypothesis!

Question 15

Endoscopy

Answer 15

An endoscope is a narrow tube with a light source, lens, and a camera that can obtain images
- Where it is inserted, will depend on what area of the digestive tract they are looking to examine

Question 16

where can the endoscopy be inserted?

Answer 16

This tube can be inserted through the mouth, anus, or a small incision

Question 17

colonoscopy

Answer 17

If inserted through the anus/rectum and into the colon, it is called a colonoscopy

Question 18

what else can endoscopy be used for?

Answer 18

Endoscopes are also used to perform some medical procedures
- They are also designed with additional tools attached - like ones to remove tissue for a biopsy or to remove a gall bladder in surgery
- Often this limits pain, recovery time, hospital stay and cost

Question 19

capsule endoscope

Answer 19

• Uses miniature and wireless technologies to make a camera that can fit into a capsule
• As it passes, it transmits photographic evidence to a receiver!