Chapter 47: Digestive System Flashcards
What is feeding?
eating food
What is ingestion?
feeding method used to take food into the digestive cavity
What is digestion?
breaking down food into chemical subunits for abosorption
What is absorption?
food being brought into cells of the organism via subunits
What is a calorie?
amount of energy required to raise the temperature of 1 g of pure water by 1 degree C
kcal per gram of carbohydrates?
4.2
kcal per gram of fats?
9.5
kcal per gram of proteins?
4.1
Some examples of malnutition?
undernutrition and overnutrition
What order do mammals use for energy storage?
1) stored fats and glycogen
2) proteins
What are essential nutrients?
certain molecules that need to be obtained in the diet bc they cannot by synthesized
What are the 9 essential amino acids?
phenylalanine, valine, threonine, tryptophan, isoleucine, methionine, leucine, lysine, and histidine
Where can you get the 9 essential amino acids and what are the results of a deficiency?
can get from meat, eggs, fish, cheese, and milk
deficiency can lead to ineffective protein synthesis
How many known human required vitamins are there?
13
Which are the 4 fat soluble vitamins?
A, D, E, K
What are the 3 trace minerals?
I, Fe, Zn
What are the 2 essential fatty acids?
linoleic acid and linolenic acid
What are the 5 steps in digestion?
1) mechanical processing
2) secretion of enzymes and other digestive aids
3) enzymatic hydrolysis
4) absorption
5) elimination
What are the 4 major layers of the gut?
1) mucosa
2) submucosa
3) muscularis
4) serosa
What is secreted by chief cells?
pepsinogen
What is secreted by parietal cells?
HCl
How does pepsinogen become pepsin?
HCL lowers pH and allows for conversion
What bacteria causes stomach ulcers?
helicobacter pylori
Where does the pancreas secrete enzymes into?
duedenum
What breaks down maltose, lactose and sucrose into individual monosaccharides?
disaccharides
What hydrolyses small peptides to individual amino acids?
aminopeptidases
What breaks nucleic acids into nucleosides?
nucleotidases
What converts nucleosides to nitrogenous bases, five-carbon sugars, and phosphates
nucleosidases
How are fats transported around in the body?
chylomicrons in the lymphatic system
What is secretin?
inhibits gastric emptying and acid production in the stomach, and stimulates HCO3 secretion
What is chelocystokinin (CCK) do?
inhibits gastric activity and stimulates secretion of pancreatic enzymes
What is glucose-dependent insulinotropic peptide (GIP)?
stimulates pancreas to release insulin, stimulates uptake and storage of glucose
What does alpha-MSH do?
inhibits appetite
What does ghrelin do?
secreted by empty stomach and binds to hypothalamus and stimulates appetite
What does leptin do?
secreted by fat cells to stop eating
Pathway of digestion of ruminants?
rumen, reticulum, rechews and swallows, omasum, abomasum
