Digestion and Absorbtion

Question 1

organs of the gi tract

Answer 1

oral cavity,
esophagus,
stomach,
small intestine,
large intestine

Question 2

accessory organs

Answer 2

salivary glands,
liver,
gall bladder,
pancreas

Question 3

the process of digestion and absorption is…

Answer 3

hunger
ingestion
digestion
absorption
transportation
utilization/metabolize
storage
exception of nutrients

Question 4

what are the mechanical processes of digestion?

Answer 4

teeth, tongue, and muscles

Question 5

what are the chemical processes of digestion?

Answer 5

enzymes (-ases) play the central role in chemical digestion

Question 6

roles of the mouth (mechanical and chemical)

Answer 6

mechanical: increases surface area of food
chemical: salivary amylase (CHO), lingual lipase (fat)

saliva triggers taste and provides protection

Question 7

roles of the mouth (mech and chem)

Answer 7

mechanical: moves and mixes food via peristalsis
chemical: some chemical digestion continues

Question 8

roles of the stomach (mech and chem)

Answer 8

mechanical: mixes and moves food

chemical: eating triggers hormone gastrin
gastic juices contains:
HCL denatures proteins, kells bacteria nd activates pepsin,
pepsin digests proteins into smaller polypeptides,
gastric lipases,
mucus to protect stomach cells

Question 9

what is HCL?

Answer 9

hydrochloric acid:
denatures the quaternary structure of a protein

activates pepsin which breaks down proteins into long chains of amino acids (i.e. polypeptides)

Question 10

what is myoglobin

Answer 10

a monomer

Question 11

what is hemoglobin

Answer 11

a heterotetramer (a2b2)

Question 12

roles of small intestine (mech and chem) duodenum, jejunum, ileum

Answer 12

mechanical: moves, mixes chyme
chemical: majority of absorption

Question 13

role of chyme in duodenum

Answer 13

fat and protein stimulate CCK

CCK causes gallbladder to contract

gallbladder secretes bile

Question 14

role of gallbladder

Answer 14

bile emulsifies fats

breaks it down into small droplets (micelles)

enables lipases to digest TG’s to mono and di-G

Question 15

what does bile contain?

Answer 15

bile salts (lecithin, cholesterol)

electrolytes (sodium, potassium, chloride and calcium)

Question 16

role of pancreas

Answer 16

bicarbonate to neutralize acidic chyme

amylase secreted to breakdown CHO

lipase secreted to breakdown fat

proteases secreted to breakdown protein

Question 17

role of the large intestine (mech and chem)

Answer 17

mech: moves non-digestible food material finer, water and bacteria

fiber fermented by gut bacteria

them: absorption of water creates a semisolid mass

Question 18

where does most absorption take place?

Answer 18

duodenum and jejunum

Question 19

what are the specialized cells and tissues called absorbing molecules?

Answer 19

microvilli and lacteals

Question 20

how does nutrient absorption work?

Answer 20

occurs through simple diffusion, facilitated diffusion, and active transport

Question 21

what do you absorb in the mouth?

Answer 21

small amounts of glucose and drugs

Question 22

what do you absorb in the stomach?

Answer 22

water

alcohol (20%)

some medium-chain FAs

aspirin and some other drugs

Question 23

what do you absorb in the small intestine?

Answer 23

95% of absorption takes place in duodenum and jejunum

peptides and amino acids

glucose, fructose, galactose

fatty acids

most vitamins

water and alcohol

minerals including calcium, magnesium, iron

Question 24

what do you absorb in the large intestine?

Answer 24

water, na, k

short chain FAs

bacteria synthesize and absorb
some b and lots of k vitamin

Question 25

where is protein digested?

Answer 25

primarily in the stomach

Question 26

where are fats digested?

Answer 26

in the small intestine

Question 27

where are CHO digested?

Answer 27

begins in the mouth

amylase breaks down cho

continues in the upper stomach