So we did talk cover the entire like elementary canal aka our gi tract again elements in elementary just referring to food and nourishment so again what is it basically a tube that runs from your mouth to your anus and we went through that tube but is that all there is to your digestive system there is more and you also have your accessory organs and the main
Accessory organs are your liver your gallbladder and your pancreas so we’re so let’s do a little backtracking and go back to the small intestines and let’s pretend we’re just done with the stomach we’re done with mixing up the bolus with gastric acid and making kind and now we’re dumping the chyme into the small intestines so what’s the first part well you have
Your duodenum and then your jejunum and ilium but let’s focus on the one in them for now so the pancreas one of our so-called accessory organs so what happens is that they see that the head of pancreas is actually cradled by the duodenum and even though the pancreas looks like it’s very solid in this picture right here the pancreas is a very very delicate organ
Made have very delicate tissues i’ve heard an analogy used like it’s like a paper tip like a bunch of sand held in a paper towel it’s like super delicate and things that okay well we have our duodenum which is part of the main gi tract because again it’s part of that big tube and part of your intestines so the duodenum is the first small part first part of the
Small intestines but it’s the intersection where you have all of these three accessory organs we’re talking going to talk about that all connects to the main gi tract at the duodenum so the liver is an again accessory is just in terms of actually location does that mean it’s not important whatsoever the liver is probably the most unoverlooked underappreciated
Organ in this entire book it’s mentioned the most in the digestive system but does much more than help with your digestive system if your liver fails the rest of your organs are going to fail that’s why they if you ever have the blood work they always check your liver enzymes to make sure your liver is healthy so things that’s very important for metabolism so not
Just your own metabolism of nutrients but also in metabolizing like when you take a drug pretty much any drug you ingest through the oral route has to all the chemicals from that eventually goes through your liver which changes it chemically and it’s also very important in homeostasis we’ll cover that really soon and there’s also the pancreas again it’s accessory
Because it’s not part of that main tube itself it’s like a branch that leads to that tube but it doesn’t develop from that elementary canal that runs from the mouth to the anus so it’s like something on the side but accessory does not mean not input accessory doesn’t mean unimportant or optional accessory just means it’s not part of the gi tract or proper so it’s
Also very important for chemical digestion it produces a lot of chemicals and enzymes and also important for metabolism as well so if you have don’t have your liver you don’t have your pancreas that is going well yeah if you don’t have a liver altogether good luck staying alive same with the pancreas they’re very essential things and we did cover the pancreas as
It related to the endocrine system but now we’re going to talk about its exocrine it’s digestive system roles and let’s talk about the pancreas first so again the pancreas what we have here the head of the pancreas is being cradled by the duodenal and then you have the body of the pancreas this is everything that’s jutting out from the head of pancreas toward
The left side of your body now the pancreatic duct this is the main duct that basically takes all the pancreatic juices that the pancreas produces and squirts it into the gi tract and that’s different from your endocrine system because remember endocrine system and hormones where do you secrete hormones what’s the primary carrier of hormones blood is the primary
Carrier of hormones right but is this secreting it into the blood in the pain in terms of like the pancreas’s role in digestive the digestive system it’s exocrine it’s exocrine secretion because it’s actually secreting it onto a surface and even though you don’t have your mouth open all the time you’ll have the anus open all the time but this part is exposed
To the environment so it is going to the it’s on the surface it’s in the surface inside of your body but it’s not in your bloodstream it’s in your gi tract so all the pancreatic juices are going to end up in your gi tract and then you also have the accessory pancreatic duct here so there are multiple routes and that’s why you have these little openings over here
Now what what does the pancreas what does crackers make well they have the pancreatic pancreatic duck and all these little branches up here so again endocrine is bloodstream and you have endocrine cells in your pancreatic eyelid so pancreatic eyelids they secrete into the bloodstream that’s why you have all this i think is the artery and all these capillaries over
Here now you have pancreatic blood vessels but exocrine secretions these are going to go in a different route they’re not going to go into the bloodstream they’re going to go inside that pancreatic duct so these are not called pancreatic eyelids the exocrine cells are called pancreatic acini so these are like different types of cells they still produce a secretion
They do produce substances and chemicals and molecules but instead of going into the bloodstream they go into the pancreatic dot and eventually into your duodenum all right so then what do they make they mix this mixture called pancreatic juice so pancreatic juice what is that well it’s made by those acini and epithelial cells that’s the exocrine secretion because
Again it’s going inside that pancreatic duct but it also has a alkaline or basic ph and why is that important well remember that gastric acid it’s super acidic that ph about like 1.5 to 3.5 well what happens if that acid keeps on traveling at that very acidic ph throughout the rest of your digestive system well if there’s any place where there is not enough mucus
That could dissolve the insides of your body right so it’s good that the pancreatic juice has an alkaline basic ph so that once you’re done mixing up that the food the bolus in your stomach and making kind that you can neutralize the chyme so it’s easier in terms of like its ph balance going through the rest of your digestive tract it also contains many enzymes
So enzymes we’re going to cover real quick and you actually produce a lot of this this is why the pancreas even though anatomically it’s like an accessory structure of the digestive tract it’s not that it’s not important it’s actually very important because it produces a lot of this juice and what’s in this juice well it has buffers that make it more toward the p
Alkaline and basic side of the ph scale it also has enzymes so remember our four types of macromolecules and again three of them are on your nutrition label so we have four broad categories of macromolecule enzymes now there’s not a single type of enzyme for each but this is our broad categories and what we have are amylases in general they break down carbohydrate
Polymers such as starches and glycogen then light pieces they break down lipids so that’s pretty easy right so they break down things like triglycerides they don’t break down cholesterol and if we have time in the metabolism chapter we might be able to talk about that but they break down triglycerides and triglycerides will cover pretty soon in this semester and
Then proteases well what does protease sound like it sounds like protein right so proteases break down polypeptides into proteins and nucleases break down nucleic acids this includes dna and rna so that’s why like even if like um a wayward virus makes itself into the gi tract if it’s not evolved to or have the defenses to survive the different enzymes and acids your
Gi tract has if there’s any like random dna or nuclei or dna or rna if you eat dna and rna these nucleuses are going to break it down as well so pancreatic enzymes what do they produce well what type of enzymes does the pancreatic pancreas produce that’s another way of rephrasing it okay so then you have pancreatic alpha amylase and that breaks down carbohydrates
Then you have pancreatic light pieces and they break down triglycerides and the prank crack proteases they break down polypeptides and then you have also pancreatic nucleuses they break down nucleic acids and this is the special thing about pancreas like some different parts of your body like you have lingual lipase you have salivary amylases in your mouth so you
Can digest carbohydrates and lipids in your mouth your stomach has well i don’t i should i forgot this in i know it’s not in the martini version but there’s gastric light paste and there’s also all these various proteases in the stomach but the pancreas is special because your pancreas produces enzymes that can digest all four types of biological macromolecules
So again this is yet another reason why the pancreas is important it produces all these enzymes that help to digest pretty much everything you can that has some sort of nutrition nutrition nutrition nutritive value and they also i don’t know what’s up with that and also they have there have all the endocrine functions as well remember the pancreas also makes
Insulin and glucagon and also some yeah you have also your delta cells and also your s cells as well so the things that the pancreas is a very vital organ and this is what we have here look at this pancreatic enzyme formula and i think you can actually buy these over the counter at like a local farm drugstore and what do you have there well what is most it has
There it’s a plant source and has amylases light pieces and proteases so say someone is having trouble or they have pancreatic insufficiency or they’re not producing enough pancreatic juice well maybe they can take a supplement that increases the amount of the enzymes so that they’re able to chemically digest their food better and get more nutrition from what
They eat so yeah notice that these are all there okay so then the pancreatic duct goes this way and it opens up here and every accessory pancreatic duct but there’s yet another tube over here what’s this third tube it’s not part of the pancreas
Transcribed from video
PHYL 142 | Digestive | Pancreatic Juice & Enzymes By doctorj808 – Anatomy \u0026 Physiology (A\u0026P) with Dr.J