Lesson 4: Specialized Digestion and Illness Flashcards
what are the different types of digestive systems?
complete, complex, and simple Ex: humans have a complete digestion system; each animal species have unique adaptations to obtain and digest food
what is an example of “unique adaptations” in animals that help them obtain and digest food?
mosquitos: have specializied mouth structure in order to obtain nutrients from sucking blood
simple digestion, what is it?
there is only one opening that serves as both the mouth and the anus (food comes in one way and goes out the same way)- called a two way digestion
what organisms have simple digestion?
simple organisms perform simple digestion: flatworms and jellyfish for instance
what is the gastrovascular cavity? what happens in it?
a simple sac that is a part of simple digestion
- food is broken down chemically in the cavity; the cells that surround the cavity are responsible for absorbing the nutrients
complex digestion, what is it?
more complex animals have complex digestive systems; food movement is in one direction
what organisms have complex digestion- give an example
earthworms, for instance, have two openings; they have specialized regions that enable the breakdown and absorption of food
what are accessory organs?
functions to support the digestive system, but are not considered a part of the digestive tract
how do accessory organs support the digestive system?
they produce enzymes and secrete substances that are needed for digestion, absorption, and excretion
food does not pass through these organs!
what are the main accessory organs?
- liver
- pancreas
- gallbladder
why are the accessory organs placed in the way that they are? what purpose does it serve?
they are placed in specific locations because it helps them carry out their specific functions and tasks
- for instance, the liver is near the gallbladder as they work together to produce and store bile
- pancreas is under the stomach as it produces substances for stomach digestion purposes
what is the pancreas? where is it found? what does it do? what are the types of hormones secreted?
a gland found between the stomach and the duodenum; it controls sugar levels (insulin) and enzymes that helps digestion
- amylase is secreted to digest starches (carbs)
- trypsin is secreted to digest proteins
- lipase is secreted to break down fats
how does the pancreas aid with digestion? what is in the substance it produces?
produces a juice made up of water, sodium bicarbonate, and digestive enzymes- the sodium bicarbonate neutralizes the stomach’s acidity, so that the digestive enzymes can do their jobs
how does the pancreas help maintain sugar levels when blood sugar is high?
pancreas releases insulin, which makes excess sugars move into cells where its used as energy or stored for later use; insulin also tells the liver to shut down sugar production
how does the pancreas help maintain sugar levels when blood sugar is low?
pancreas release a hormone called glucagon, which tells the body’s cells and liver to release stored sugars back into the bloodstream
so generally, what keeps our sugar levels balanced?
the pancreas use of insulin and glucagon
if the pancreas gets weakened by something such as a disease, what could happen?
the organ’s ability to produce insulin may be reduced or extinguished, which can lead to diabetes
what exactly happens with no insulin release?
sugar builds up in the blood, which hardens blood vessels- this can cause heart attacks, kidney failures, and strokes
what happens if we don’t have our pancreas?
sugar levels go haywire and too much sugar would be in our blood
what is the liver’s role in digestion?
to release bile that breaks down fats into smaller droplets called micelles in order to make them easier to digest
- the liver also filters any toxins found in the blood such as alcohol
- stores carbs as glycogens
- stores fat soluble vitamins
- liver can regenerate! doesn’t mean its invincible to harm though
what happens when the liver detects a useless or harmful toxin in the blood?
it either converts it into a product that cannot hurt the body or it isolates it and whisks it away (by channeling it to the kidneys and intestine to be excreted)
what is the main substance that the liver produces?
bile! its a bitter greenish liquid that is stored in the gallbladder and used to break down fats
what is the gallbladder used for? what happens when fats enter the duodenum?
where bile is stored; when fats enter the duodenum, the gallbladder is stimulated to begin contracting, which pushes bile through the cystic duct and into the duodenum
what is acid reflux? how does it occur? where is it located?
a digestive illness that is caused when the gastroesophageal sphincter does not fully close
- located between the esophagus and the stomach
what does it mean if you constantly have heartburn/ acid reflux? how does it happen? what are some consequences of it?
GERD: gastroesophageal reflux disease
- the relaxed sphincter allows swallowed foods to reenter the esophagus and irritates it
- overtime you can develop esophagitus, and may lead to respiratory problems (asthma, etc)
GERD symptoms
- heartburn
- nausea
- problems swallowing
- bad breath
- hoarseness
- sore throat
- regurgitation (food comes up throat)
what are stomach ulcers? whats it caused by and how does it occur?
a digestive illness caused by a harmful bacteria called helicobacter pylori (H. pylori)
- occurs because the bacteria has the ability to adapt and survive in highly acidic conditions in the stomach; they can do this by secreting enzymes that neutralize the acidic content
how is the stomach ULCER itself produced? (due to the bacteria)
the ulcers are produced when the bacteria burrows itself into the protective mucus layer in our stomach- this prevents the production of the mucus, which allows our stomach acids to make open sores on our stomach linings called ulcers
what are the problems with having ulcers?
- they bleed and become very painful
- can become very dangerous as the H pylori bacteria may infect the entire body
how can you get rid of these ulcers?
can be treated with antibiotics!
what are endoscopies? whats it used for?
narrow tube with a light source, lens, and camera; used by putting it inside you and analyzing the GI tract
- also used to perform medical procedures and surgeries (gallbladder removal for instance)
how is the tube of endoscopies inserted?
through the mouth, anus, or small incision (when incisions are made and inserted through them, its called an endoscopy)
what is a colonoscopy?
inserted through the anus/rectum and into the colon
why are endoscopies done?
when patients complain about symptoms of possible digestive illnesses
how was the digestive tract previously analyzed? when was the endoscopy discovered and upgraded?
through surgical openings on patients- in 1895, endoscopy was discovered and in 1997, the upgraded capsule endoscopy was discovered
