Digestion Of Food

Question 1

two major functions of buccal cavity

Answer 1

mastication of food
facilitation of swallowing

Question 2

_____ in saliva helps in lubricating and adhering the masticated food particles into a _______

Answer 2

mucus
bolus

Question 3

bolus is conveyed into the ________ and then oesophagus by swallowing or __________

Answer 3

pharynx
deglutition

Question 4

bolus passes down the oesophagus by successive waves of muscular contractions called

Answer 4

peristalsis

Question 5

which sphincter controls the passage of food into the stomach

Answer 5

gastro-oesophageal

Question 6

what does saliva contain

Answer 6

electrolytes (Na+, K+, Cl-, HCO3-)
enzymes (salivary amylase, lysozyme)

Question 7

which is the carbohydrate splitting enzyme

Answer 7

salivary amylase

Question 8

where does the chemical process of digestion begin

Answer 8

in oral cavity with the hydrolytic action of salivary amylase

Question 9

about ______ percent of starch is hydrolysed in the oral cavity by salivary amylase with optimum pH ___ into a disaccharide _________

Answer 9

30
6.8
maltose

Question 10

function of lysozyme

Answer 10

acts as an antibacterial agent that prevents infections

Question 11

mucosa of stomach has _______ glands

Answer 11

gastric

Question 12

three major types of cells of gastric glands

Answer 12

mucus neck cells
peptic/chief cells
parietal/oxyntic cells

Question 13

what do mucus neck cells secrete

Answer 13

mucus

Question 14

what do peptic or chief cells secrete

Answer 14

proenzyme pepsinogen

Question 15

parietal or oxyntic cells secrete what

Answer 15

HCl and intrinsic factor (factor essential for absorption of vitamin B12)

Question 16

how long does the stomach store food

Answer 16

4 to 5 hours

Question 17

food after being churned in the stomach is called

Answer 17

chyme

Question 18

which is the proteolytic enzyme of the stomach

Answer 18

pepsin

Question 19

the proenzyme pepsinogen, on exposure to _______ gets coverted to active enzyme called _______

Answer 19

HCl
pepsin

Question 20

pepsin converts proteins into _______ and ________

Answer 20

proteoses
peptones (peptides)

Question 21

the _______ and ___________ in gastric juice play an important role in the lubrication and protection of the mucosal epithelium from excoriation by __________

Answer 21

mucus
bicarbonates
highly concentrated HCl

Question 22

HCl provides the acidic pH of ______ which is optimal for pepsin

Answer 22

1.8

Question 23

__________ is a proteolytic enzyme found in gastric juice of infants which helps in the digestion of milk proteins

Answer 23

rennin

Question 24

which other enzyme is secreted for lipids in small amounts by gastric glands

Answer 24

lipases

Question 25

which secretions are released into the small intestine

Answer 25

bile pancreatic juice intestinal juice

Question 26

pancreatic juice and bile are released through which duct

Answer 26

hepato-pancreatic

Question 27

which inactive enzymes does the pancreatic juice contain

Answer 27

trypsinogen chymotrypsinogen procarboxypeptidases amylases lipases nucleases

Question 28

trypsinogen is activated by which enzyme

Answer 28

enterokinase

Question 29

enterokinase is secreted by

Answer 29

intestinal mucosa

Question 30

active form of trypsinogen is called

Answer 30

trypsin

Question 31

other enzymes in the pancreatic juice are activated by which enzyme

Answer 31

trypsin

Question 32

what does bile contain

Answer 32

bile pigments (bilirubin and biliverdin) bile salts cholesterol phospholipids

Question 33

does bile contain enzymes

Answer 33

no

Question 34

what does bile do

Answer 34

helps in emulsification of fats activates lipases

Question 35

during emulsification of fats, they are broken down into very small _______

Answer 35

micelles

Question 36

intestinal mucosal epithelium has ______ cells which secrete mucus

Answer 36

goblet

Question 37

intestinal juice is also called

Answer 37

succus entericus

Question 38

which secretions constitute intestinal juice

Answer 38

secretions of brush border cells of mucosa secretions of goblet cells

Question 39

enzymes present in succus entericus

Answer 39

disaccharidases (eg. maltases) dipeptidases lipases nucleosidases

Question 40

________ along with _________ from the pancreatic juice protect the intestinal mucosa from acid as well as provide an alkaline medium of pH ___ for enzymatic activities _________ also help in this

Answer 40

mucus bicarbonates 7.8 sub-mucosal glands

Question 41

sub-mucosal glands are called

Answer 41

brunner's glands

Question 42

proteins, peptones, proteoses are acted upon by which enzymes to form what

Answer 42

trypsin/chymotrypsin carboxypeptidase dipeptides

Question 43

polysaccharides/carbohydrates/starch are hydrolysed by which enzyme to form what

Answer 43

pancreatic amylase disaccharides

Question 44

fats are broken down by _________ with the help of ____________ into ____________________ and ______________

Answer 44

lipases bile diglycerides monoglycerides

Question 45

_________ in the pancreatic juice acts on nucleic acids to form ___________ and _____

Answer 45

nucleases nucleotides nucleosides

Question 46

dipeptides are broken down into which substances using which enzyme

Answer 46

amino acids dipeptidases

Question 47

maltose is broken down into which substances using which enzyme

Answer 47

glucose and glucose maltase

Question 48

lactose is broken down into which substances using which enzyme

Answer 48

glucose and galactose lactase

Question 49

sucrose is broken down into which substances using which enzyme

Answer 49

glucose and fructose sucrase

Question 50

nucleotides are converted to nucleosides using which enzyme nucleosides are broken down into which substances using which enzyme

Answer 50

nucleotidases sugars and bases nucleosidases

Question 51

diglycerides and monoglycerides and broken down into which substances using which enzyme

Answer 51

fatty acids and glycerol lipases

Question 52

breakdown of macromolecules occurs where

Answer 52

duodenum

Question 53

after breakdown in duodenum, where are the simple substances absorbed

Answer 53

jejunum and ileum

Question 54

functions of the large intestine

Answer 54

absorption of some water, minerals and certain drugs secretion of mucus which helps in adhering the waste particles together and lubricating it for an easy passage

Question 55

what are the undigested and unabsorbed substances called

Answer 55

faeces

Question 56

faeces enters into caecum of large intestine through _____________, which prevents the back flow of matter

Answer 56

ileo-caecal valve

Question 57

removal of faeces from body is known as

Answer 57

defaecation