Nutrients Digestion and Absorption: Carbohydrates and Proteins

Question 1

What and where are disaccharides broken down?

Answer 1

Broken down into monosaccharides (glucose) by brush border enzymes in the small intestine

Question 2

What is the monosaccharides of:
Lactose
Sucrose
Maltose

Answer 2

Glucose and galactose

Glucose and fructose

Glucose and glucose

Question 3

What are the two forms of starch and their bonding

Answer 3

Amylose and amylopectin

Both glucose monomer linked by alpha 1 glycosidic bonds

Question 4

What polysaccharide cannot be broken down in vertebras

what is its structure

Answer 4

Cellulose

unbranched linear glucose molecules linked by beta 1-4 glycosidic bonds

Question 5

What is the linkage in polysaccharide glycogen

Answer 5

Glucose monomers linked by alpha 1-4 glycosidic bonds

Question 6

What enzymes breaks down the polysaccarides glycogen and starch

and where can it be found

Answer 6

amylase

Found in your saliva

Question 7

Whats the name of the out facing membrane on the brush border of the small intestine

Answer 7

apical membrane

Question 8

What is the name of the inside facing membrane of the brush border of the small intestine

Answer 8

Baso-Lateral facing membrane

Question 9

What is found on a brush border, and what is its purpose

Answer 9

Micro Vili covered surface

Increasing the surface area

Question 10

What is the three pathways across the small intestine

Answer 10

Transcellular - right travel through apical and basolateral membranes

Paracellualr - travel through tight junction of brush border cells

Vectorial - a proteins carriers that travel in one direction

Question 11

What does glucose couple up with in secondary active transport across the brush border and why?

Answer 11

Na

There is a continually driving force for sodium to enter the cell

Question 12

Why cant glucose cross the brush border cell on its own

Answer 12

Is water soluble and charged

Question 13

what is name of transporter that glucose and sodium both bind to

Answer 13

SGLT1

Question 14

What happens to glucose when it is pumped into the cell

Answer 14

Glucose stays in the cell until a concentration gradient of above 5.5 mmol/L is created and glucose is transported across the cell

Question 15

What is the name of the glucose transporter that transports glucose out the cell and into the blood

Answer 15

GLUT 2

Question 16

What happens to sodium once it enters the cell

Answer 16

Sodium enters the cells and is pumped out by active transport

Question 17

How is fructose transported across the cell and into the blood from the small intestine

Answer 17

GLUT 5 transports fructose from lumen into the cell and fructose is pumped out the cell through GLUT2 into the blood

Question 18

Why does fructose enter the small intestine without coupling to sodium

Answer 18

Their isn’t a fructose gradient present

Question 19

What are the enzymes that hydrolyse peptide bonds in protein digestion

Answer 19

Protease and peptidase

Question 20

What is the difference between endo and exopeptidase

Answer 20

Endopeptidase cuts peptide chain anywhere minus the terminal ends

Expedites cuts the peptide chain at the terminal ends

Question 21

How does an amino acid cross the brush border of the small intestine

Answer 21

Uses the driving force of sodium and combines with sodium at the SAAT1 transporter

Question 22

How does sodium and amino acid pass from the small intestine to the blood

Answer 22

Sodium is actively transported across the cell

Amino acid is transported across into the blood

Question 23

What is the name of the transported for dipeptides and most proteins across the brush boarder

Answer 23

PepT1

Question 24

What couples up with Dipeptide to cross the brush border

Answer 24

Hydrogen

Question 25

What is the name of the NA/H transporter across the brush boarder

Answer 25

NHE3

Question 26

Due to movement of hydrogen across the brush boarder what is created

Answer 26

An acid microclimate