CASE 1-6 BLOCK 1.5
Digestion and Defence I
25 APRIL 2016
MARIEKE DE JONG
ITM
,Case 1: Out Through Your Nose? ............................................................................................................3
Anatomy of the Mouth and Oesophagus ............................................................................................3
Physiology of the Oral Cavity and Oesophagus ...................................................................................4
Salivation..........................................................................................................................................4
Swallowing .......................................................................................................................................6
Taste.................................................................................................................................................7
Smell ................................................................................................................................................7
Coughing, Hunger and Stomach Rumbling ..........................................................................................7
Coughing ..........................................................................................................................................7
Hunger .............................................................................................................................................7
Stomach rumbling ............................................................................................................................8
Heimlich Manoeuvre ...........................................................................................................................8
Case 2: Heartburn....................................................................................................................................9
Anatomy and Histology of the Stomach ..............................................................................................9
Gastric Juice Production ....................................................................................................................10
HCl production ...............................................................................................................................11
Protection Mechanisms and Safeguards ...........................................................................................12
Cultural Influences on Acid Reflux .....................................................................................................12
Gastric Motility and Emptying ...........................................................................................................12
Case 3: Painful Obstruction ..................................................................................................................14
Anatomy and Histology of the Liver ..................................................................................................14
Functions of the Liver ........................................................................................................................15
Bile .................................................................................................................................................15
Haemoglobin breakdown ..............................................................................................................16
Jaundice .........................................................................................................................................17
Storage ...........................................................................................................................................17
Cleansing ........................................................................................................................................17
Protein formation ..........................................................................................................................17
Anatomy and Histology of the Gall Bladder ......................................................................................17
Functions of the Gall Bladder ............................................................................................................17
Obstructed Choledochus Duct on X-Ray............................................................................................18
Influence of Alcohol Consumption on the Liver ................................................................................18
Case 4: Chronic Pancreatitis and Hormonal Regulation ......................................................................19
Anatomy and Histology of the Pancreas ...........................................................................................19
Functions............................................................................................................................................21
Endocrine .......................................................................................................................................21
1
, Glucagon: ...................................................................................................................................21
Insulin:........................................................................................................................................22
Exocrine .........................................................................................................................................22
Alcohol use and influence on the pancreas .......................................................................................24
Case 5: Lactose Intolerance ..................................................................................................................25
Anatomy and Histology of the Small Intestine ..................................................................................25
Functions of the Small Intestine ........................................................................................................26
Breakdown .....................................................................................................................................26
Carbohydrates ...........................................................................................................................26
Proteins ......................................................................................................................................26
Lipids ..........................................................................................................................................27
Absorption .....................................................................................................................................27
Carbohydrates ...........................................................................................................................27
Proteins ......................................................................................................................................27
Lipids ..........................................................................................................................................27
Nucleic Acid................................................................................................................................27
Vitamins .....................................................................................................................................28
Minerals .....................................................................................................................................28
Motility...........................................................................................................................................28
Anatomy and Histology of the Colon .................................................................................................29
Functions of the Colon .......................................................................................................................29
Breakdown .....................................................................................................................................29
Absorption .....................................................................................................................................29
Motility...........................................................................................................................................29
Lactose Intolerance (Including Geographical Distribution) ...............................................................30
Case 6: Metabolism ...............................................................................................................................31
Metabolic Pathways of Proteins ........................................................................................................31
Metabolic Pathways of Carbohydrates .............................................................................................31
Metabolic Pathways of Lipids ............................................................................................................34
Bibliography ..........................................................................................................................................36
2
,Case 1: Out Through Your Nose?
Anatomy of the Mouth and Oesophagus
Figure 1
Figure 2
3
, The vestibule is the space between the cheeks, lips and teeth. The area between the teeth and gums
is the oral cavity proper.
The mouth is also called the oral or buccal cavity. It opens anteriorly into the oral orifice and
posteriorly into the oropharynx. It’s lined with stratified squamous epithelium. On the gums, hard
palate and the back of the tongue, this is keratinised for strength.
The oral mucosa produce defensin (a peptide that kills bacteria).
The orbicularis oris is the main muscle in the lips, the buccinators in the cheeks.
The labial frenulum attaches each lip to the gums in the middle anteriorly.
Innervation is done by the mandibular branch of CN V:
- Anterior division: lateral pterygoid, temporal and masseter muscles
- Auriculotemporal: ear
- Inferior dental: lower lip, teeth, periodontal ligaments and gums
- Lingual: anterior 2/3 of the tongue, floor of the mouth, gums on the lingual side
The tongue has a body and a base or root. It is divided into an anterior and posterior section by the
sulcus terminalis (V-shaped groove). It’s composed of skeletal muscle and glands, covered by
mucous membranes.
There are intrinsic and extrinsic fibres. Intrinsic fibres are arranged in a vertical, horizontal and
longitudinal direction. There are also glands located between the muscle fibres.
The tongue has papillae: fungiform and foliate anterior and lateral, circumvallate at the base and
filiform in the terminal sulcus. Most papillae have taste buds, filiform do not. The back of the tongue
has lymphatic nodules, with many lymphocytes in the crypts. Foliate papillae look like grooves and
are located on the lateral posterior tongue.
Teeth have two main parts: a crown and a root. The junction is called the neck. The pulp cavity is
filled with connective tissue. It’s surrounded by dentine (similar to bone), enamel on the crown and
cementin on the root.
Figure 3
The oesophagus has an inner layer of circular and an outer layer of longitudinal muscle. In the upper
1/3 this is skeletal, the rest is smooth. The transition between the two is gradual. Both types are
controlled by the vagus nerve.
Physiology of the Oral Cavity and Oesophagus
Salivation
Functions of saliva:
- Cleansing the mouth
- Dissolving food chemicals for taste
4
Digestion and Defence I
25 APRIL 2016
MARIEKE DE JONG
ITM
,Case 1: Out Through Your Nose? ............................................................................................................3
Anatomy of the Mouth and Oesophagus ............................................................................................3
Physiology of the Oral Cavity and Oesophagus ...................................................................................4
Salivation..........................................................................................................................................4
Swallowing .......................................................................................................................................6
Taste.................................................................................................................................................7
Smell ................................................................................................................................................7
Coughing, Hunger and Stomach Rumbling ..........................................................................................7
Coughing ..........................................................................................................................................7
Hunger .............................................................................................................................................7
Stomach rumbling ............................................................................................................................8
Heimlich Manoeuvre ...........................................................................................................................8
Case 2: Heartburn....................................................................................................................................9
Anatomy and Histology of the Stomach ..............................................................................................9
Gastric Juice Production ....................................................................................................................10
HCl production ...............................................................................................................................11
Protection Mechanisms and Safeguards ...........................................................................................12
Cultural Influences on Acid Reflux .....................................................................................................12
Gastric Motility and Emptying ...........................................................................................................12
Case 3: Painful Obstruction ..................................................................................................................14
Anatomy and Histology of the Liver ..................................................................................................14
Functions of the Liver ........................................................................................................................15
Bile .................................................................................................................................................15
Haemoglobin breakdown ..............................................................................................................16
Jaundice .........................................................................................................................................17
Storage ...........................................................................................................................................17
Cleansing ........................................................................................................................................17
Protein formation ..........................................................................................................................17
Anatomy and Histology of the Gall Bladder ......................................................................................17
Functions of the Gall Bladder ............................................................................................................17
Obstructed Choledochus Duct on X-Ray............................................................................................18
Influence of Alcohol Consumption on the Liver ................................................................................18
Case 4: Chronic Pancreatitis and Hormonal Regulation ......................................................................19
Anatomy and Histology of the Pancreas ...........................................................................................19
Functions............................................................................................................................................21
Endocrine .......................................................................................................................................21
1
, Glucagon: ...................................................................................................................................21
Insulin:........................................................................................................................................22
Exocrine .........................................................................................................................................22
Alcohol use and influence on the pancreas .......................................................................................24
Case 5: Lactose Intolerance ..................................................................................................................25
Anatomy and Histology of the Small Intestine ..................................................................................25
Functions of the Small Intestine ........................................................................................................26
Breakdown .....................................................................................................................................26
Carbohydrates ...........................................................................................................................26
Proteins ......................................................................................................................................26
Lipids ..........................................................................................................................................27
Absorption .....................................................................................................................................27
Carbohydrates ...........................................................................................................................27
Proteins ......................................................................................................................................27
Lipids ..........................................................................................................................................27
Nucleic Acid................................................................................................................................27
Vitamins .....................................................................................................................................28
Minerals .....................................................................................................................................28
Motility...........................................................................................................................................28
Anatomy and Histology of the Colon .................................................................................................29
Functions of the Colon .......................................................................................................................29
Breakdown .....................................................................................................................................29
Absorption .....................................................................................................................................29
Motility...........................................................................................................................................29
Lactose Intolerance (Including Geographical Distribution) ...............................................................30
Case 6: Metabolism ...............................................................................................................................31
Metabolic Pathways of Proteins ........................................................................................................31
Metabolic Pathways of Carbohydrates .............................................................................................31
Metabolic Pathways of Lipids ............................................................................................................34
Bibliography ..........................................................................................................................................36
2
,Case 1: Out Through Your Nose?
Anatomy of the Mouth and Oesophagus
Figure 1
Figure 2
3
, The vestibule is the space between the cheeks, lips and teeth. The area between the teeth and gums
is the oral cavity proper.
The mouth is also called the oral or buccal cavity. It opens anteriorly into the oral orifice and
posteriorly into the oropharynx. It’s lined with stratified squamous epithelium. On the gums, hard
palate and the back of the tongue, this is keratinised for strength.
The oral mucosa produce defensin (a peptide that kills bacteria).
The orbicularis oris is the main muscle in the lips, the buccinators in the cheeks.
The labial frenulum attaches each lip to the gums in the middle anteriorly.
Innervation is done by the mandibular branch of CN V:
- Anterior division: lateral pterygoid, temporal and masseter muscles
- Auriculotemporal: ear
- Inferior dental: lower lip, teeth, periodontal ligaments and gums
- Lingual: anterior 2/3 of the tongue, floor of the mouth, gums on the lingual side
The tongue has a body and a base or root. It is divided into an anterior and posterior section by the
sulcus terminalis (V-shaped groove). It’s composed of skeletal muscle and glands, covered by
mucous membranes.
There are intrinsic and extrinsic fibres. Intrinsic fibres are arranged in a vertical, horizontal and
longitudinal direction. There are also glands located between the muscle fibres.
The tongue has papillae: fungiform and foliate anterior and lateral, circumvallate at the base and
filiform in the terminal sulcus. Most papillae have taste buds, filiform do not. The back of the tongue
has lymphatic nodules, with many lymphocytes in the crypts. Foliate papillae look like grooves and
are located on the lateral posterior tongue.
Teeth have two main parts: a crown and a root. The junction is called the neck. The pulp cavity is
filled with connective tissue. It’s surrounded by dentine (similar to bone), enamel on the crown and
cementin on the root.
Figure 3
The oesophagus has an inner layer of circular and an outer layer of longitudinal muscle. In the upper
1/3 this is skeletal, the rest is smooth. The transition between the two is gradual. Both types are
controlled by the vagus nerve.
Physiology of the Oral Cavity and Oesophagus
Salivation
Functions of saliva:
- Cleansing the mouth
- Dissolving food chemicals for taste
4
