absorption of carbs and proteins

Question 1

starch is ……. branched

Answer 1

moderately

Question 2

what is the smallest unit of sugar

Answer 2

monosaccharides

Question 2

what is sucrose made from

Answer 2

glucose
fructose

Question 2

glycogen is …. branched

Answer 2

highly

Question 3

disaccharides

Answer 3

two single units joined together

Question 3

polysaccharides are made from …..

Answer 3

monosaccharides

Question 4

glucose + galactose

Answer 4

lactose

Question 5

2 x glucose molecules form …..

Answer 5

maltose

Question 6

define polysaccarhides

Answer 6

3 or many million units of sugar

Question 7

examples of polysaccharides

Question 8

what is the carbs storage in plants

Answer 8

starch

Question 9

what is the carb storage in animals

Answer 9

glycogen

Question 10

how to make a polysaccharide into a di

Answer 10

uses salivary amylase
pancreatic amylase
intestinal (brush border) enzymes

Question 11

disaccharide into monosaccharide

Answer 11

intestinal (brush border) enzymes
-intestinal maltase
-intestinal sucrase
-intestinal lactase

Question 12

dietary carbs/saccharides

Answer 12

-meet body’s energy needs - glucose
- proteins and fats are important components of cells and tissue - shouldn’t waste
- feed brain and nervous systems
- keep digestive system fit
- add bulk to foods
- ingestible carbs are beneficial

Question 13

describe the enzymes involved in carb digestion + describe the process

Answer 13

poly -> di
- salivary amylase
- pancreatic amylase
- intestinal (brush border) enzymes

di -> mono
- intestinal (brush border enzymes)
- intestinal:
maltase, sucrase, lactase

Question 14

where are some of the carb digestive enzymes located

Answer 14

intestinal villus brush border

Question 15

desrcibe the stages of carb/monosaccharide absorption

Answer 15

1. glucose, galactose, fructose absorbed
2. fructose, galactose -> glucose
3. glucose released into blood
4. energy, glycogen, adipose tissue

Question 16

dietary protein

Answer 16

-absorption is highly efficient
- body uses to build + repair
- provide essential am. acids for protein synthesis + nitrogen atoms for N compounds
-energy from protein when lipid + carbs aren’t available
-lose lots of proteins daily

Question 17

where are proteins lost to daily

Answer 17

mucins
cell debris

Answer 18

proteins

Question 19

levels of protein structure

Answer 19

1. protein
2. polypeptides
3. peptides
4. di- & tri- peptides
5. amino acids

Question 19

getting energy from proteins is …..

Answer 19

expensive + inefficient

Question 20

how many different kinds of amino acids are there

Answer 20

20

Question 21

what bond holds peptides together

Answer 21

peptide bond

Question 22

di/tri amino acids can be absorbed by the ..... ....

Answer 22

small intestine

Question 23

how many amino acids are essential

Answer 23

9

Question 24

what type of digestion does the stomach provide

Answer 24

mechanical

Question 25

what % of protein digestion occurs in the stomach

Answer 25

10-15%

Question 25

what does pepsin do

Answer 25

convert larger proteins into smaller proteins

Question 26

stomach for protein digestion - full explanation

Answer 26

- mechanical digestion - HCl converts pepsinogen into active pepsin - HCl denatures protein - INCREASE SURFACE ARE FOR PEPSIN - pepsin - large proteins into smaller peptides -10-15%

Question 26

HCl converts pepsinogen into ... .....

Answer 26

active pepsin

Question 27

how is the surface area for pepsin increased

Answer 27

HCl denatures the protein

Question 28

what are the 2 types of enzymes involved in protein digestion

Answer 28

endopeptidases exopeptidases

Question 29

intestines for protein digestion - full explanation

Answer 29

- receives denatured polypeptides from stomach - pancreatic enzymes - extensive and rapid digestion - breaks small peptides into AA’s -85-90%

Question 30

endopeptidases - explain

Answer 30

attack bonds in the centre of peptide chains: -gastric pepsin -pancreatic trypsin

Question 31

exopeptidases - explain

Answer 31

split AA's one at a time: -pancreatic enzymes -intestinal (brush border) enzymes -enterocyte cytoplasm enzymes

Question 32

why are whole proteins rarely absorbed

Answer 32

no transporters on enterocytes + too big to 'squeeze' between cells

Question 33

newborn - whole protein absorption

Answer 33

few days after birth whole milk protein maternal anitbodies by pinocytosis

Question 34

what is pinocytosis

Answer 34

invagination of cell membrane to form vesicles

Question 35

monosaccharide absorption - full

Answer 35

- all 3 utilise same basolateral transporter GLUT2 - exit the enterocyte into blood by FACILITATED DIFFUSION

Question 36

small peptide and AA absorption

Answer 36

FREE AA ABSORPTION AA apical transporters in the brush border surface. These free AA’s are absorbed using Na+/K+ ATPase linked secondary active, facilitated diffusion or simple diffusion mechanisms. PEPTIDE ABSORPTION Di - & Tri-peptide apical transporters in the brush border surface AA transporters on the basolateral surface to allow exit of single AAs

Question 36

examples of ways in which proteins enter the gut

Answer 36

diet digestive enzymes microoragnisms mucus plasma proteins desquamated epithelial cells