Digestion: Lipids (M2)

Question 1

digestion is a form of

Answer 1

catabolism

Question 2

what is catabolism

Answer 2

hydrolytic process that breaks down large food molecules into smaller ones

Question 3

large food molecules

Answer 3

carbohydrates
proteins
lipids

Question 4

small food molecules

Answer 4

monosaccharides
amino acids
fatty acids

Question 5

how do we obtain lipids

Answer 5

synthesized or obtained through diet

Question 6

lipids are classified due to their

Answer 6

hydrophobicity

Question 7

do lipids dissolve in water

Answer 7

no, they cluster together away from water

Question 8

what is a TAG composed of

Answer 8

3 fatty acids + glycerol (sugar)

Question 9

TAGs comprise __% of dietary lipids

Answer 9

90

Question 10

what do lipids include

Answer 10

triacylglycerol (triglyceride, TAG)
cholesterol
phospholipids

Question 11

what are phospholipids composed of

Answer 11

2 fatty acids + glycerol +phosphate + 1 of 4 polar groups

Question 12

what is cholesterol composed of

Answer 12

steroid core of 4 fused rings + side chains

Question 13

limited digestion occurs in

Answer 13

mouth and stomach

Question 14

what hydrolyzes fatty acids with less than/equal to 12 carbons

Answer 14

lingual lipases and gastric lipases

Question 15

fat globules leave the __ and enter the __

Answer 15

stomach; small intestine

Question 16

what are bicarbonate and lipases secreted from

Answer 16

pancreas into small intestine

Question 17

what is bicarbonate

Answer 17

buffer that neutralizes acidic stomach contents

Question 18

what does pancreatic lipas hydrolyze

Answer 18

triglycerides into monoglyceride and (2) free fatty acides

Question 19

what are bile salts secreted from

Answer 19

gallbladder into small intestine

Question 20

what emulsifies fat globules

Answer 20

amphipathic molecules

Question 21

emulsification

Answer 21

increases surface area of lipids and makes them more accessible to digestive enzymes

Question 22

what enzymes are secreted by pancreas

Answer 22

trypsin
chemotrypsin
lipases

Question 23

bile salts surround

Answer 23

fat droplets forming micelles

Question 24

micelles

Answer 24

core of lipids (hydrophobic regions inside and hydrophilic regions outside) surrounded by bile salts

Question 25

what do micelles transport

Answer 25

transport lipids through intestinal lumen to epithelial lining

Question 26

once micelles reach __ of the __, they are _____

Answer 26

once micelles reach epithelial lining of the small intestine, they are absorbed into enterocytes

Question 27

how do micelles enter enterocytes

Answer 27

simple diffusion

Question 28

what are bile salts absorbed in

Answer 28

the more distal small intestine and transported back to the liver through the portal vein

Question 29

what happens in the enterocyte

Answer 29

TAG is reformed and packaged into chylomicrons, along with other lipids

Question 30

what are chylomicrons

Answer 30

water-soluble lipoproteins. micelle with protein

Question 31

what do chylomicrons transport

Answer 31

lipids through the bloodstream from the intestine, and remnants return to the liver for recycling

Question 32

what is lacteal

Answer 32

lymphatic vessels of small intestine that store digestive fats

Question 33

chylomicrons enter __ and bypass __

Answer 33

chylomicrons enter lymph capillaries and bypass blood capillaries

Question 34

within blood capillaries chylomicrons are

Answer 34

digested

Question 35

lipoprotein lipase (LPL)

Answer 35

hydrolyzes triglycerides into fatty aids and glycerol

Question 36

chylomicron remnants are

Answer 36

transported to the liver

Question 37

in the liver, chylomicron remnants are

Answer 37

recycled and TAG is reformed

Question 38

TAG, along with other lipids (mainly cholesterol), is packaged into

Answer 38

VLDL (very low density lipoproteins) for transport through bloodstream to tissues

Question 39

bad cholesterol

Answer 39

LDL and VLDL

Question 40

within blood capillaries, VLDL is

Answer 40

digested

Question 41

glycerol returns to the

Answer 41

liver to be reused

Question 42

fatty acids enter cells to be

Answer 42

used as an energy source or stored as triglycerides

Question 43

loss of triglycerides and some apoproteins converts

Answer 43

VLDL into LDL

Question 44

LDL is an important carrier of

Answer 44

cholesterol to tissues

Question 45

cholesterol can be

Answer 45

deposited in the cell membrane, used to make Vitamin D, bile acid, or steroid hormones

Question 46

HDL carries

Answer 46

excess cholesterol away from tissues to the liver

Question 47

what do high amount of HDL prevent against

Answer 47

cardiovascular disease

Question 48

why are non-hdl bad

Answer 48

higher risk of cardiovascular disease