Digestive processes

Question 1

Digestive processes

Answer 1

Ingestion 
Secretion
Mixing & Propulsion
Digestion 
Absorption
Defecation

Question 2

The Mouth

Answer 2

Membranes produce mucus to lubricate the mouth

Three pairs of glands which produce up to 1500ml per day of saliva

Saliva consists of :- Water, Mineral salts, mucus, immunoglobulins, blood clotting factors and the salivary enzymes

Question 3

The tongue

Answer 3

Muscular organ which is attached to the hyoid bone and the mandible.

Functions :-

Organ of taste

Assists in mastication

Assists in swallowing

Assists in speech

Question 4

The pharynx

Answer 4

The bolus of food is pushed into the pharynx (a muscular tube) by the tongue

Question 5

The epiglottis

Answer 5

Is superior to the larynx and the junction of the oesophagus

On swallowing, the epiglottis blocks the larynx, to allow food to go down the oesophagus without affecting the airway

Question 6

The oesophagus

Answer 6

A soft muscular tube [flat] 25 to 30cm long

Runs down the gap in the “C” shaped rings of the cartilage surrounding the trachea and passes through the diaphragm at the level of the 10th thoracic vertebra to become the stomach

Moves the bolus of food on towards the stomach by “Peristalsis”

Question 7

The Stomach

Answer 7

Can hold 1500ml

The upper opening of the stomach is the cardiac sphincter or the lower oesophogeal sphincter

The lower opening of the stomach is the pyloric sphincter

The fundus of the stomach lies in the left upper quadrant of the abdomen just inferior to the diaphragm

Question 8

Function of the stomach

Answer 8

Mix/churn food (Mechanical Digestion) with gastric juices containing hydrochloric acid and enzymes that begins the digestion of food (Chemical Digestion)

Mucous lining prevents the walls of the stomach being digested

Food + acid + enzymes = chyme (milky substance)

Food spends 2-6 hours in the stomach

Question 9

The small intestine

Answer 9

Continuous with the stomach at the pyloric sphincter and leads into the large intestine

Over 6m long and lies in the abdominal cavity surrounded by the large intestine

Chemical digestion of food is completed and most of the absorption of nutrient materials takes place

Described in three parts, which are continuous with each other
Duodenum
Jejunum
Ileum

Question 10

The duodenum

Answer 10

25cm long

Curves around the head of the pancreas

Pancreatic and bile duct combine to a shared duct for entry into the duodenum

Question 11

Large intestine / Colon

Answer 11

1.5m long

Begins at the “caecum” in the right iliac fossa and terminates at the rectum and anal canal deep in the pelvis

It forms an arch around the coiled up small intestine

Water absorption

Made up of ascending, transverse, descending and sigmoid portions

Question 12

Rectum and Anus

Answer 12

13cm long
The colon terminates at the rectum, which leads to the anus.

Defaecation is controlled by the internal and external anal sphincters

Question 13

The liver

Answer 13

2.3kg, 2 lobes

Nutrient rich blood passes via the Portal vein from the intestines to the liver

Blood leaves the liver via the hepatic veins, which almost immediately enter the inferior vena-cava

Involved in: Conversion
                   Breakdown
                  Production
                Secretion
             Storage
                Synthesis
                   Metabolism

Question 14

The spleen

Answer 14

Size varies but approx. 12cm long, 7cm wide and 2.5cm thick

Weighs approx. 200g

Functions:

Produce new leucocytes (white blood cells

Store erythrocytes (red blood cells)

Destroy old red blood cells

Question 15

The kidneys

Answer 15

2 bean shaped organs Each 6cm wide, 4cm thick, weighing 130g

Positioned either side of the lumbar vertebrae

Right lies lower than left to make room for the liver

Adrenal glands lie over each kidney and secrete adrenaline and other hormones

Question 16

Addison’s disease

Answer 16

Using your JRCALC or any other resources and making sure to reference your sources, investigate the following questions….

Which glands are affected by Addision’s disease?
The release of which hormones are affected in Addison’s disease?
List the common pre existing conditions associated with Addison’s disease
What is the prevalence of Addison’s disease and who does it mainly affect?
The disease is slow to develop what is it commonly misdiagnosed as?
What is the mnemonic for the symptoms and what does it stand for?
Addison’s crisis patients are time critical. Why?
Briefly describe your management of an Addison’s patient in ‘crisis’