Nutrient Digestion and Absorption 1

Question 1

What are the principal dietary constituents?

Answer 1

protein
carbohydrates
fat
water
vitamins
minerals

Question 2

give 3 hexose sugars examples

Answer 2

glucose,galactose,fructose

Question 3

What are disaccharides?

Answer 3

Two monosaccharides linked together by a glycosidic bond

Question 4

What breaks down disaccharides?

Answer 4

Brush border enzymes in small intestine

Question 5

What makes up lactose? sucrose? Maltose?

Answer 5

Lactose: glucose + Galactose
Sucrose: glucose + fructose
Maltose: glucose + glucose

Question 6

what is alpha-amylose

Answer 6

glucose linked in straight chains

Question 7

What is amylopectin?

Answer 7

Glucose chains highly branched

Question 8

What bond do amylases act on (saliva and pancreas)

Answer 8

glycosidic alpha 1,4 bonds

Question 9

What is cellulose

Answer 9

unbranched linear chains of glucose linked by beta 1,4 glycosidic bonds

Question 10

How does glucose move through lumen of small intestine to blood

Answer 10

through SGLT1 and GLUT-2 transporters

Question 11

What is the conc of glucose in blood

Answer 11

5 mmol/L

Question 12

What are the transporters of fructose

Answer 12

GLUT-5 at lumen and GLUT-2 to blood

Question 13

what are peptides

Answer 13

small proteins that are 3-10 amino acids in length

Question 14

What are the types of exopeptidases?

Answer 14

aminopeptidases and carboxyptidases

Question 15

What transporter do amino acids move through

Answer 15

SAAT1

sodium coupled amino acid transporter

Question 16

How do dipeptides and tripeptides pass through and how does this affect the acid microclimate

Answer 16

PepT1 : absorbs dipeptides and tripeptides. Does it coupling to hydrogen (proton motive force). NHE3 then expels the H in exchange of Na that leaves for K to enter and this causes the acid microclimate