Nutrient & Digestion 1

Question 1

What are the principle dietary constituents?

Answer 1

Fats, Proteins & Carbohydrates

Question 2

What are the main monosaccharides?

Answer 2

Glucose, Galactose & Fructose

Question 3

What are the main disaccharides?

Answer 3

Sucrose, Maltose & Lactose

Question 4

What is the term given to the enzymes that breakdown disaccharides?

Answer 4

Brush border enzymes

Question 5

What is maltose made up of?

Answer 5

Glucose & Glucose

Question 6

What is sucrose made up of?

Answer 6

Glucose & Fructose

Question 7

What is lactose made up of?

Answer 7

Glucose & Galactose

Question 8

What are the names of the enzymes that convert maltose, sucrose and lactose to their monomeric constituents?

Answer 8

Maltase, Sucrase & Lactase

Question 9

What are the three main polysaccharides found in nature?

Answer 9

Starch, Glycogen & Cellulose

Question 10

What are the two types of starch?

Answer 10

Alpaha-amylose & Amylopectin

Question 11

Which form of starch is highly branched?

Answer 11

Amylopectin

Question 12

Which form of starch forms straight chains?

Answer 12

Alpha-amylose

Question 13

What bond creates the polysaccharides starch and glycogen?

Answer 13

Alpha 1,4 Glycosidic

Question 14

In order, name the monosaccharides, disaccharides and polysaccharides

Answer 14

Mono - Glucose, galactose & fructose
Di - Lactose, maltose & sucrose
Poly - Starch, glycogen & cellulose

Question 15

What is the term given to the movement of nutrients through a cell?

Answer 15

Transcellular

Question 16

What is the term given to the movement of nutrients through the gaps between cells, in the tight junction areas?

Answer 16

Paracellular

Question 17

What is the name given to the movement of nutrients via a transporter in the apical and / or basolateral membranes?

Answer 17

Vectorial

Question 18

Describe the process by which glucose and galactose are taken up into the blood from the intestines

Answer 18

Glucose from food enters the intestine.

Glucose & Na are taken up with sodium via a symporter (SGTL1) on the apical surface

Glucose and Na concentration rises in the intracellular compartment

Glucose is moved out via GLUT-2 in the basolateral membrane

Na is removed via a Na / K ATPase

The build up on Na causes an osmotic gradient between the intestine and blood. This results in water movement from the lumen to the blood

Question 19

Describe the process by which fructose is taken up into the blood from the intestines

Answer 19

Fructose enters via GLUT-5

Fructose leaves via GLUT-2

Question 20

Describe how amino acids are taken up into the blood from the intestines

Answer 20

Amino acids enter with Na VIA SAAT1 alongside Na

Amino acids are transported out via a transporter and Na is transported out via Na / K ATPase

Osmotic gradient of Na inside the intestines and inside the blood causes water movement into the blood via para-cellular processes

Question 21

Describe the movement of dipeptides accross the small intestine

Answer 21

Dipeptides enter via PEPT1 along with H ions

Concentration of both increases

H is pumped out via NHE3 in exchange for Na

Na levels increase

Na is pumped out via Na / K ATPase

Dipeptide is transported out via unknown transporter