Digestive System Flashcards
Ingestion?
Combination of mastication by deglutition moving a bolus of food to stomach
Prehension
The process of acquiring food through seizing, grasping or other methods
Digestion
Physiological actions of the stomach and enzymatic breakdown of food to an absorbable form
Absorption
Passage of materials from the lumen of the intestine into the blood stream
Metabolism
Chemical reactions where food components are altered to produce or store energy
Excretion
Process of eliminating waste products of digestion from tissues and organs from the body
Pylorus?
Regulates movement of chyme from stomach to duodenum
Cardia
Area with sphincter that comes above it when food not being swallowed
Fundus
Contains key gastric glands with parietal chief and mucous cells
Pyloric Antrum
Regulates production of hydrochloric acid; secretes gastrin into blood when food present
Gastric Mucosa?
Columnar Epithelium, a thin layer of loose areolar connective tissue and muscle. Thin layer that separates it from the submucosa.
Submucosa
Comprised of dense, irregular, connective tissue separating it from mucosa. Contains blood and lymphatic vessels and nerves which supply the mucosa.
Muscular Externa
Region of muscle responsible for peristaltic movements of the stomach. Comprised of three layers.
Order of muscle layers in stomach?
- Longitudinal
- Circular
- Oblique
Order of muscle layers in stomach?
- Longitudinal
- Circular
- Oblique
Longitudinal
Generates peristaltic movement contractions moving food through the stomach
Oblique
Churns and breaks down the bolus of food
Circular
Mixes bolus of food via forceful, grinding contractions, moving it to the duodenum
Goblet Cells
Produce mucus from stomach wall to protect against auto digestion
Parietal Cells
Produces HCl from stomach wall, lowering pH so pepsin can break down protein
Chief Cells
Produces pepsinogen which when combined with Hal converts to pepsin to break down protein
HCl?
Hydrochloric Acid
Which hormone is responsible for stimulating the parietal cells to produce Hydrochloric Acid?
Gastrin
The mix of partly digested food and secretions from the stomach is referred to as?
Chyme
Chyme?
Product in the stomach following food material breakdown, food enters the stomach at gastric pits within gastric lining secrete various gastric juices.
Main site for absorption of products following digestion?
Small Intestine
Duodenum
Presence of chyme here stimulates production of pancreatic juices and bile
Jejunum
Contains large villi, caudal section absorption of majority of nutrients
Ileum
Absorption of electrolytes, Vit B12 and bile salts
What is absorbed by the colon?
Vitamins, Electrolytes and Water
Which cell secretes HCl in the stomach lining?
Parietal Cells
The gall bladder stores bile and delivers it to the large intestine via the common bile duct.
Select one:
True
False
False
Large Intestine is made up of?
Colon, Caecum, Rectum and Anus
What are the villi of the small intestine lined with?
Simple columnar
Deglutition?
Swallowing
BMR?
energy required to sustain vital functions e.g. heart beat, breathing, nervous activity
Peristalsis?
involuntary movement of the intestines moving the contents along the lumen
Absorption
transfer of substances; in particular digested food from the lumen of the alimentary tract to blood or lymph
Digestion?
the process of breaking down food for absorption in the gut
A role of HCl in the stomach is to?
Kills bacteria
Which of the following enzymes breaks down proteins into peptides and amino acids? Select one: a. Proteases. b. Peptidases c. Bile salts. d. Lipases.
Protease
How does digested food finally reach the bloodstream?
It is absorbed into the blood through blood vessels
Tongue?
Manipulation of food during mastication and swallowing. Also taste, grooming and thermoregulation
Colon
Absorbs water, vitamins and electrolytes to aid in compaction and passage of faeces
Small Intestine
Receive pancreatic enzymes and bile, secrete own juices and enzymes and digest and absorb nutrients
Caecum
No function in carnivores. Site for bacterial breakdown of plant matter for some herbivores
Rectum?
Temporary storage site for faecal waste
Ascending Colon
Begin process of extraction of waste and other nutrients from waste material
Caecum?
Site of microbial action on digestive food stuffs
Transverse Colon?
Absorbs water and salt
Descending Colon?
Storage of waste which gradually solidifies as it moves through this colon
If faeces is not eliminated from the body, it returns to the colon where more what is absorbed to cause constipation which could lead to faecal impaction?
Water
Black Faeces indicates?
Bleeding in upper GI tract
Bright red faeces?
Undigested blood in lower GI tract
Orange Faeces?
Liver issue
Yellow Faeces?
food intolerance
Pink/Purple Faeces?
HGE
Where does starch first undergo chemical digestion?
In the mouth
Saliva contains an enzyme to partially digest what?
Starch
What is the function of sodium bicarbonate ( NaHCO3 ) in pancreatic juice?
Neutralises acid chyme
What would inhibit trypsin’s ability to form an enzyme-substrate complex?
pH of 3
Which of these is not a feature of the mucosa of the gastrointestinal tract?
Myenteric Plexus
Vitamins and amino acids are produced in the large intestine by what?
Bacteria
