Presentation on theme: "Liver Functions Part II 3E1 From where we left off…"— Presentation transcript:
Liver Functions Part II 3E1
From where we left off…
In the small intestines Complete digestion occurs in the small intestines End products (glucose, amino acids, fatty acids, glycerol) diffuse into the blood vessels lining the small intestines. This process is called Absorption.
Some animal samples Guess what is the organ shown! From which animal?
Adaptation of the small intestine for absorption
Structure of small intestine
What do you see in the intestinal walls?
How do the folds and villi help in absorption? The presence of folds and villi in the intestinal wall increase surface area
More adaptations from the small intestine the epithelial cell of the intestinal wall surface areaOne-celled thick epithelial wall and microvilli further increases surface area
The small intestines What makes the small intestines suitable for Absorption? 1) Elongated ileum, Inner surface of the ileum is folded These features provide large surface area:vol for absorption 2) Villi and microvilli
The small intestines What makes the small intestines suitable for Absorption? 3) Many blood vessels lining the small intestines
Absorption Absorption occurs by: –Diffusion –Active transport After absorption, Glucose and amino acids enter the blood capilliaries Glycerol and fatty acids enter the lacteals
How does absorption takes place in the intestines Absorption of fatty acids and glycerol Glycerol and fatty acids diffuse into the epithelium where they combined to form minute fat globules and enters the lacteals Fat globules mix with lymph in the lacteals to form chyle Liver is not involved *
Assimilation and function of the liver
Overview Role of DigestionMouth & Oesophagus Gall Bladder &Pancreas Stomach Large Intestine & Others Small Intestine
Lesson objectives: Describe the fate of glucose, amino acids and fats in the blood that leaves the intestines, after a meal. Describe the 5 major roles that the liver plays in the human body –Regulation of blood glucose concentration –Deamination of amino acids –Production of bile –Detoxication –Iron storage
Fate of glucose and amino acids
Transport and utilization of absorbed foods In the Liver! Types of absorbed food products Glucose Amino acids Fats
From the small intestines to the liver! How?? Connected by a vein called Hepatic Portal Vein!
Guess which part the vein connects to the intestine? A B C D
Carbohydrate metabolism Hepatic portal vein transports sugars like glucose from the intestines to the liver
Question! Receives 5 glucose molecules from the intestines Requires only 3 glucose molecules for breathing
how many molecules of glucose do you think the liver would transport to the lungs? Receives 5 glucose molecules from the intestines Requires only 3 glucose molecules for breathing
Liver in Glucose metabolism Hepatic portal vein
In the liver…. 1. Some glucose carried in the blood to be distributed to the rest of the body -Tissue respiration Carbohydrate metabolism
In the liver…. - Glucose (excess) Glycogen (stored) Hormone : Insulin -If the glucose level is too low in the blood Glycogen (stored) Glucose Hormone: Glucagon Insulin and glucagon
What about the amino acids absorbed by the small intestines? Similar route as sugars: Intestines hepatic portal vein liver general blood circulation
Liver in Protein metabolism Hepatic portal vein
Fate of amino acids Amino acid metabolism Converted into protoplasm Used for growth & repair of worn- out parts Formation of enzymes & hormones Excess amino acids cannot be stored : Deamination
Deamination N H H COH || O R | C | H Amino group Carbon residue Ammonia (toxic) Urea (non-toxic) glucose glycogen
Intestines lacteal lymphatic vessels blood rest of the body Fat metabolism Fate of Fats maintenance of cell membranes Production of hormones Excess fats stored in adipose tissues When glucose supply is low, fats will be oxidised in the liver to provide energy (Liver not involved)
Summary: 5 major roles that the liver plays –Regulation of blood glucose concentration –Deamination of amino acids –Iron storage –Production of bile –Detoxication
True/False Liver is part of the alimentary canal
True/False Carbohydrates are digested in the liver
True/False Excess amino acids are deaminated
True/False Fats are absorbed in the liver and transport to other parts of the body for usage.