Liver and Gallbladder – Digestive System Organs (Nursing)

00:02 So before we get to the small intestine, it's important to talk about the other accessory organs that are going to be involved or associate with the small intestine.

00:14 These include the liver which is going to have the function of producing bile, which is very important or necessary for the emulsification of fat.

00:25 The gallbladder which is going to store the bile until it is needed for fat emulsification.

00:33 And also the pancreas.

00:36 The pancreas is very important because it supplies most of the enzymes needed to digest chyme.

00:43 It is also going to contain bicarbonate which helps to neutralize that stomach acid that's going to be entering into the duodenum.

00:55 Taking a closer look at the liver at the microscopic level.

00:59 We find that the liver is made up of liver lobules.

01:04 These are hexagonal structures and functional units composed of plates of hepatocyte that are going to filter and process nutrient-rich blood that returns to the liver by way of hepatic portal circulation.

01:21 Each lobule contains a central vein.

01:24 It is located in its longitudinal axis.

01:29 At the corner of each lobule you have what's known as the portal triad.

01:35 This is going to include a branch of the hepatic artery, which is going to supply oxygen a branch of the hepatic portal vein, which is going to bring nutrient-rich blood from the intestines, and a bile duct which is going to receive bile from the bile canaliculi.

01:56 Hepatocyte also have an increased rough and smooth ER Golgi apparatus, peroxisomes, and mitochondria.

02:06 These help with the function of the hepatocyte, which is to produce about 900 milliliters of bile per day.

02:16 The hepatocyte are also going to be processing blood-borne nutrients such as glucose, which will then be stored as glycogen as well as making plasma proteins.

02:30 The hepatocyte are also going to be responsible for the storage of fat soluble vitamins.

02:36 And also the hepatocytes are very important in detoxification.

02:42 This includes things like converting ammonia to urea when we take in or when we bring in a lot of amino acids, but it's also important for drugs that we bring into our bodies.

02:55 This is where the detoxification process and our bodies are is going take place.

03:01 Recall that the hepatocyte of the liver are going to be responsible for creating bile.

03:08 Bile is a yellow-green alkaline solution that contains bile salts which are the cholesterol derivatives that are going to function in fat emulsification and fat absorption in the small intestines.

03:24 Bile also contains bilirubin, which is a pigment that is formed from heme.

03:30 This pigment is broken down by bacteria in the intestines to stercobilin and from here it gives the feces it's brown color.

03:41 Also found in bile we have cholesterol, triglycerides, phospholipids and some electrolytes.

03:51 The entero hepatic circulation is going to involve as recycling mechanism that is going to conserve our bile salts.

04:00 Most of our bile salts are reabsorbed into the blood by the ileum, which is the last part of the small intestine.

04:08 From there it is returned to the liver by way of the hepatic portal blood it is then re secreted in newly-formed bile.

04:19 So in our bodies about 95% of our bile salts that are secreted are then recycled.

04:26 So that we're only making about 5% of nubile each time it circulates.

04:34 The next major organ that is important for the functioning of the small intestine is the gallbladder.

04:42 The gallbladder is a thin-walled muscular sac found on the ventral surface of the liver.

04:49 It functions to store and concentrate bile by absorbing water and ions in the bile.

04:57 It contains many honeycomb folds that allow for it to expand as it fills.

05:04 And then when stimulated muscular contractions are going to release that bile into a duct known as the cystic duct.

05:14 This is going to then flow into the bile duct.