Digestive System Flashcards
What are the organs in the digestive tract?
1) . Tongue.
2) . Salivary glands.
3) . Epiglottis.
4) . Esophagus.
5) . Stomach.
6) . Liver.
7) . Galbladder.
8) . Duodenum.
9) . Pancreas.
10) . Colon (large intestine).
11) . Ileum (small intestine).
12) . Appendix.
13) . Rectum.
14) . Anus.
What are the accessory organs involved in digestion?
1) . Bile production (in liver).
2) . Hepatic duct.
3) . Bile storage (in galbladder).
4) . Digestive enzyme production (in pancreas).
5) . Pancreatic duct.
6) . Bile duct.
7) . Duodenum.
What are the 4 quadrants in the abdominal cavity?
1) . Right upper quadrant.
2) . Left upper quadrant.
3) . Right lower quadrant.
4) . Left lower quadrant.
What are the organs in each abdominal quadrant?
1). Right upper quadrant =
- Liver.
- Galbladder.
- Transverse colon.
- Pancreas.
2). Left upper quadrant =
- Spleen.
- Stomach.
3). Right lower quadrant =
- Small intestine.
- Ascending colon.
4). Left lower quadrant =
- Descending colon.
- Signoid colon.
What component of the digestive system is responsible for ingestion?
Mouth.
What component of the digestive system is responsible for propulsion?
Movement of peristalsis =
- oesophagus.
- stomach.
- small/large intestine.
What components of the digestive system are responsible for digestion?
1). Mouth =
- tongue.
- teeth.
- saliva.
2) . Stomach =
- churn (chemically/mechanically).
3) . Small intestine =
- chemically.
What component of the digestive system are responsible for absorption?
Small intestine =
- digested molecules move across the GI tract in to the blood.
What component of the digestive system are responsible for assimilation?
Molecules move from the blood to the cells and become part of the body tissue.
What component of the digestive system is responsible for eliminating waste?
Rectum and anus.
What are the functions of saliva?
- Break down starch.
- Enzyme (lysozyme) destroys bacteria.
- Contains bicarbonate which neutralises acid preventing dental cavities.
What prevents food from entering the trachea?
Epiglottis.
Where does swallowing move food?
Mouth –> pharyx –> oesophagus.
What function is the pharynx important in?
Respiration.
What are the four layers of the digestive tract wall?
- Mucosa (1st layer).
- Submucosa (2nd layer).
- Muscularis (3rd layer).
- Serosa (outer layer).
What do the 4 layers of the GI wall surround?
Lumen (in the centre).
Where does the GI tract start/end?
Start = mouth.
End = anus.
What tissue makes up the mucosa?
Epithelial tissue.
Why is the mucosa subjected to wear and tear?
Food is in direct contact with it.
What are the different types of epithelial cells involved in the GI tract?
1). Squamous cells =
- mouth.
- oesophagus.
- rectum.
2). Columnar cells =
- stomach.
- small intestine.
- colon.
What specialised cells secrete mucus in to mucosa?
Goblet cells.
What specialised cells secrete chemicals needed for digestion?
- Chief cells.
- Parietal cells.
What type of tissue make up the submucosa?
Loose connective tissue.
What does the submucosa contain?
Nerves, blood and lymph vessels.
What does the blood supply to the submucosa allow?
Nourishment of tissues and absorbs products of digestion.
What 2 layers of smooth muscle does the muscularis contain?
1) . Circular.
2) . Longitudinal.
What is responsible for peristalsis in the muscularis?
Coordinated contraction.
What type of muscle tissue is responsible for the voluntary parts of swallowing (mouth…)?
Skeletal muscle.
What type of tissue makes up the serosa?
Loose fibrous tissue.
What does the serosa contain?
Nerves, blood and lymph vessels.
What is the main function of serosa?
Protection.
What does the oesophaguss connect the pharynx to?
Stomach.
What is the wall of the oesophagus made up of?
Muscular tissue.
Why doe mucus glands secrete mucus in the oesophagus?
To keep the lining moist and lubricated.
What causes peristalsis in the oesophagus?
Contraction of circular and longitudinal muscles.
Why does the oesophagus have an upward curve as it goes into the diaphragm?
To prevent food backflow.
What prevents reflux in the oesphagus?
Cardiac/lower sphincter.
What 3 parts does the stomach divide into?
1) . Fundus =
- near cardiac sphincter.
2) . Body =
- middle part.
3) . Antrum =
- lower part.
What sphincter does the antrum (lower part of stomach) contain?
Pyloric sphincter.
What is your stomachs capacity?
500ml - 4L or 6.5L.
What allows expansion in the stomach?
Rugae (folds) –> flatten for extra room.
What is chyme?
Mixture produced by the stomach by mixing food with gastric juice (churning).
Where does the chyme get squirted to?
In to the dueodenum via the pyloric sphincter.
What are the specialised cells in the gastric mucosa?
- Goblet cells.
- Parietal cells.
- G cells.
- Chief cells.
What do goblet cells do in the gastric mucosa?
Produce mucus to coat and protect stomach lining.
What do parietal cells do in the gastric mucosa?
Produce hydrochloric acid and intrinsic factor.
What do G cells do in the gastric mucosa?
Produce hormone (gastrin) which regulates gastric secretion.
What do chief cells do in the gastric mucosa?
Produce pepsinogen –> chemically breaks down protein molecules.
Summarise the specialised cells functions in gastric mucosa?
1) . Goblet cells =
- mucus (coat + protect).
2) . Parietal cells =
- hydrochloric + intrinsic factor (absorb vit B12).
3) . G cells =
- gastrin (regulate).
4) . Chief cells =
- pepsinogen (break down protein).
What role does mucus have when goblet cells secrete it?
Protects the mucosal lining against the acidic environment.
What 3 sections is the small intestine divided into?
1) . Duodenum.
2) . Jejunum.
3) . Ileum.
What is the duodenum?
- Secretes alkaline mucus = neutralises acidic chyme.
- Liver and pancreas connect to it.
What is the jejunum?
Follows duodenum.
What is the ileum?
- Follows jejunum.
- Attached to large intestine at the ileocaecal sphincter.
Where does the process of digestion end?
Small intestine.
What are carbohydrates broken down into (during digestion)?
Simple sugars.
What are proteins broken down into (during digestion)?
Amino acids.
What are fats broken down into (during digestion)?
Fatty acids and glycerol.
Where is 90% of digested food absorbed?
Small intestines walls.
What transport mechanisms allow digested food to be absorbed in the small intestine?
- Diffusion.
- Active transport.
Where do undigested and unabsorbed food enter?
Large intestine.
What are the functions of the large intestine?
- Absorption of water and electrolytes.
- Storage and elimination of faeces.
- Bacteria digest some polysaccharides.
- Bacteria produce vitamins K+B.
- Appendix has immune functions.
What valve prevents feaces going back into the ileum?
Ileocaecal valve.
What is the function of the liver in digestion?
Makes bile which emulsifies fats and acid absorption.
What is the function of the gal bladder in digestion?
Stores bile ready for secretion in to the duodenum.
What is the function of the pancreas in digestion?
Makes pancreatic juice.
What does pancreatic juice contain?
- Digestive enzymes.
- Bicarbonate ions.