Download DIGESTIVE SYSTEM IN HUMAN BIOLOGY 2 Human Physiology

DIGESTIVE SYSTEM IN
HUMAN
BIOLOGY 2
Human Physiology => study of the body and the its function
Digestive System in Human
The food that we ate cannot be directly absorbed by our body organs. For the food to
be able to be absorbed by intestines flake cell the food must be digested firs by
digestive organs.
Digestive tract extend beginning from mouth to intestines organs that form digestve
tract :
mouth (oral cavity) => pharynx =>throat=>stomach=>small intestines=> anus
Oral cavity : -teeth
-tounge
-salivary glands (glandula salivales)
Teeth (32) => 8, 4, 8, 12
based on its shap and fanction, teeth are separated into 4 kind :
1. Insisivus (gigi seri)
=> flat shape and sharp.
2. Incisor
(gigi taring)
=> sharp to tear food.
3. Premolar (geraham depan)
=> curved to gnaw food.
4. Molar
(geraham belakang) => curved to smoothem food.
Tongue




mix the food in the oral cavity
push the food down when swallowing
clean the mouth
make voice
 as gostatory organ
Salivary gland
Is found in oral cavity
Pharynxis
pharynx is the back park of mouth which is also the upper part of throat. In the
pharynx, there is a hole that lies in the part that goes to the troat. This hole is called
glottis. Glottis has valve called epiglottis. Epiglottis has function to pravent food from
entering respiratory tract and the make food go into the throat.
Pharyx is divided into three part :
1. Naso pharynx
2. Oro pharynx
3. Larungo pharynx
The length of pharynx => 7 cm
Throat (kerongkongan / esoafagus)
Consists of 3 layers :
1. The outermost part => connective tissue fibers.
2. The middle layer is muscle.
3. The inner layer => epithelia tissue.
The entering of food from throat to stomach is coused by paristaltic movement.
Stomach (lambung / ventrikel)
stomach is the part of digestive tract in the form of a big sac, located in the
abdominal cavity a little left under the last ribs.
Stomach is divided into 3 parts, those are:
1. Cardia : upper part near liver.
2. Fundus: middle part which hangs.
3. Pylorus: bottom part near smooth intestines.
Stomach wall consists of several layers of enlengthened, circular or crossed muscle
tissue. If these muscles contract alternatingly, it will cause the food to be mixet and
formed a thick fluid called chyme.
The fundus produces gastric juice that contains various kinds of substancess such as
water, ions, organic salts, myosin (Hcl mucus), and digestive enzymes.
The production of gastric juice is influenced by :
(1) Based on the amount of food that enters the stomach.
(2) Emotion.
The function of HCl (Chloric acid) :
(1) to change the pH in stomach to be acid => destroy germs.
(2) To activate enzymes produced by gastric juice.
(3) To control open and close the valve between stomach and duoddenum (usus 12
jari).
(4) To stimulate the secretion of gastic juice.
Small Intestines
The length of small intestine is about 8,25 m.
-Divided into thee (3) part :
1. Duodenum (usus 12 jari) panjang 0,25 m.
2. jejunum (usus kosong) panjang 7 m.
3. Ileum (usus penyeerapan) panjang 1 m.
enzymes produced by intestinal juice, those are :
a) Erepsinogen (proteinase that is not active)
b) Disaccharose (sucrase, lactase, maltose)
hydrolize disaccharide => monosaccharid
c) Intestine lipase => hydrolize fat to fatty acid and glycerin.
d) Enterokinase in an activator => activate enzyme which are not active yet.
Food digestion finish inn the jujunum with its final product => food essence. Then
food essence is absorbed by ileum flake.
Absorption of carbohydrate => monosaccharides.
Monosaccharides that is very important => glucose
Absorption of protein => amino acid
Absorption of fat => fatty acid and glycerin
Large Intestine
Large intestine consist of thick intestine (colon) and intestine axis (ractum).
The food that is not absorbed will enter into colon and in the colon, the remains of
food will be rot by Escherichia coli bacteri found in the colon. In the colon also
happens the regulation of water level.
Bettween small intestines and large intestines, there is an appendix canal called
caecum appendix. In the cuecum appendix there is appendix.
Anus
Final end of digestive tract. Anus wall consists of 2 muscle layers :
 skeletal muscle
 smooth muscle
Digestive glands (kelenjar pencernaan)
A) Salivary glands (kelenjar ludah)
Found in the oral cavity. There are 3 pair of these glands :
1. Parotid gland(salivary glands near ear).
=>produce of juice that contains only water.
2. Submandibular glands (salivary glans under tongue / rahang bawah
)
=>produce a juice that contains water and mucus (lendir)
3. Sublingual glands (salivary glands under tongue)
=>produce juice that contains water and mucus.
These 3 pairs of glands excrete kurang lebih 2,5 lt saliva daily
Several functions of saliva :
1. To ease the swallow and digestion of food.
2. To digest food chemically because it produces ptyalin enzyme.
Ptyalin enzyme => hydrolize amilumto maltose (work in pH 7
condition)
3. To protect membranes of oral cavity from acid, base, heat, and
cold.
B) Liver
A big digestive gland found in the body. The weight kurang lebih 1,5 kg.
Liver :
 Reddish brown colour
 Lies in the right part of abdominal cavity under diaphragma.
 Divided into 2 lobes which have equal size.
Several functions of liver :
1. To form bile (empedu)
2. As the storing place of several substances => glycogen, vitamin A, D, E, K,
B12.
3. As the formation place of several substances such as bile, albumin, globin,
antibody, fibrinogen, prothrombin, cholesterol.
4. To neutralize poisonous compounds which enter the body.
5. As an excretory organ function to filter bilirubin and dischage it and also
enter into the bile.
Bile => a liquid greenish colour and bitterr taste.
Bile => stored in gall bladder that lies under the liver. Everyday , liver excretes 1
lt of bile into gall bladder Functions of bile :
 To digest and ease the absorpton of fat
 Has role in excretory process (carries metabolism wasete matter)
Panceas
Pancreas => enlengthened gland found behind stomach.
Pancreas => to excrete digestive enzymes and hormones and also control the
glucose
level in the blood.
Pancreas produces pancreatic juice. Pancreatice juice countains :
1. Trypsinogen (proteinase that is not activeated)
trypsinogen is activated by enterokinase to be tripsin => hydrolyze pepton to amino
acid.
2. The carbohydate of pancreas is disaccharase
Disaccharase => hydrolize disaccharide to monosaccharide
The important disaccharide are
a) maltose => hydrolize maltose to 2 glukose molecules
b) sucrase => hydrolize sucrase to glucose and frucctose
c) lactase => hydrolize lactose to glucose and galactose
3. Pancreatic lipase (stepsin) has function to hydrolize fat emulsion to fatty acid
and glycerin.
4. NaHCO3 salt => give base condition(suasana basa) to the surrounding of
pancreatice juice. Therefore enzymes pancreatice juice are activate in base
surrounding.
Human physiology is the science of the mechanical, physical, bioelectrical, and
biochemical functions of humans in good health, their organs, and the cell of which
they are composed. In simple term”Human Physiology” is the study of the body and
its functions in each of the different systems in any living body. Physiology focuses
principally at the level of organs and systems. Most aspects of human physiology are
closely homologus to corresponding aspects of animal physiology, and animal
experimentation has provided much of the foundation of physiology knowledge.
Anatomy and physiology are closely related field of study : anatomy, the study of
form, and physiology, the study of function, are intrinsically tied and are studied in
tandem as part of a medical curriculum.
HUMAN DIGESTIVE SYSTEM
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