Carbohydrates

Question 0

Name 4 major groups of carbohydrates?

Answer 0

Monosaccharides
Disaccharides
Oligosccharides
Polygosaccharides

Question 1

What three nutrients are required for the function of insulin?

Answer 1

B3, Chromium and Gluatmine

Question 2

What are two examples of monosaccharides?

Answer 2

Glucose and Fructose

Question 3

Name some examples of disaccharides

Answer 3

Lactose, sucrose, and maltose.

Question 4

What are considered Oligosaccharides?

Answer 4

Many of the disaccharides are considered Oligosaccharides, such as Lactose, maltose and sucrose.

Question 5

What are some examples of polygosaccharides

Answer 5

Glycogen and starches

Question 6

Which of the four types of carbohydrate is considered the most healthy?

Answer 6

Polysaccharides, as the body needs to break them down, creating a low GI effect.

Question 7

What are the hydrolytic enzymes called responsible for the break down of the polygosaccharides?

Answer 7

Glycosidase and Carbohydrase

Question 8

What are the 3 types of transport?

Answer 8

1) Active transport
2) Facilitated diffusion
3) Simple diffusion

Question 9

What is active transport?

Answer 9

It is sodium dependant transport that flows against the concentration gradient via a protein channel.

Question 10

What is facilitated diffusion?

Answer 10

where the use of protein channels aids transport through a cell membrane with the concentration gradient, this means it flows from high concentration to low concentration

Question 11

What is simple diffusion?

Answer 11

it is passive diffusion, it is the flow with the concentration gradient and does not need any energy or a protein channel.

Question 12

Where is Glucose and Galactose absorbed and how?

Answer 12

• They are absorbed from the small intestines to mucosal cells via an ATP-sodium/glucose symporter (SGLT1)
• When concentrations are high they are absorbed by a facilitated transport known as the glucose transporter type 2 (GLUT 2)

Question 13

What are the factors involved in GLUT 2 regulation?

Answer 13

Elevated blood sugar and insulin levels; high fructose diets, high-saturated fat diets and artificial sweeteners.

Question 14

What is the transporter protein required for the absorption of Fructose?

Answer 14

Facilitated transport via the GLUT 5 transporter. However it is increased when GLUT 2 is present.

Question 15

What is the digestive enzyme responsible for disaccharides?

Answer 15

Disaccharidase

Question 16

What are the forms of the 4 disaccharidases?

Answer 16

1) Lactase
2) Sucrase
3) Maltase
4) Isomaltase

Question 17

what is the enzyme involved in the breakdown of dietary polysaccharides?

Answer 17

alpha amylase (glycosidase)

Question 18

Where does alpha amylase act?

Answer 18

in the mouth, however the pancreas also produces it and it is utilised in the duodenum.

Question 19

How is a monosacharide like glucose or galactose digested/absorbed?

Answer 19

• its absorbed from the SI to mucosal cells via ATP- Sodium/glucose symporter (SGLT1)
• However at high conc absorbed by facilitated transport (GLUT2)

Question 20

How is a Disaccharide such as Lactose is digested/absorbed?

Answer 20

• occurs in the upper SI
• The disaccharide needs to be broken down by disaccharidase
• The disaccharide actively occurs in the microvilli of the brush boarder

Question 21

How is a a polysaccharide such as starches digested/absorbed?

Answer 21

• the key enzyme involved is alpha amylase (glycosidase)
• the enzyme breaks down the 1,4 glycosidic linkages
• alpha amylase is active in the mouth, then inactivated in the stomach due to high acidity, then it is present in the duodenum from pancreatic alpha amylase

Question 22

How and where are Glucosee, galactose an fructose absorbed?

Answer 22

across the basolateral border by a facilitated transport (GLUT 2)

Question 23

What are known to regulate the glucose concentration in the intestinal wall?

Answer 23

GLUT 2 transporters

Question 24

What other factor are involved in the regulation of GLUT 2?

Answer 24

sweetness receptors, high-fructose diet, high saturated fat diets and artificial sweeteners. All of these cause this GLUT 2 receptor count to go up, therefore more GLUT 2 receptors present mean that there is more glucose absorbed.

Question 25

Where does Fructose go to, and what influences its uptake?

Answer 25

It goes to the liver first, however its increased when GLUT 2 is present.

Question 26

What is the name of the transporter that facilitates the absorption of Fructose?

Answer 26

GLUT 5 however it can exit the enterocytes via GLUT 2 but only down a concentration gradient.

Question 27

Where does disaccharide digestion occur?

Answer 27

in the upper small intestine

Question 28

What is the name of the digestive enzyme involved in the uptake of a disaccharide and where does the activity occur?

Answer 28

Disaccharidase, in the microvilli of the mucosal cells (brush border).

Question 29

What is the primary enzyme involved in the breakdown of polysaccharides?

Answer 29

alpha amylase (Glycosidase)

Question 30

What organ also produces alpha amylase?

Answer 30

The pancreas, which then utilises it within the duodenum

Question 31

What type of transport do Glucose, Fructose, and Galactose use to cross the basolateral border?

Answer 31

facilitated transport via GLUT 2 receptor

Question 32

What does the liver do to Galactose and Fructose?

Answer 32

they are metabolised and broken down into glucose derivatives or catabolised for energy depending on the livers requirements.

Question 33

Why are diabetics told to exercise?

Answer 33

To increase glucose uptake into the muscle via GLUT 4 receptor

Question 34

What is blood Glucose level controlled by?

Answer 34

Insulin and Glycogon

Question 35

What makes up a GLUT Glucose transporter?

Answer 35

1) Has a specific binding site for the molecule being transported
2) Undergoes a change in shape upon binding
3) Has the ability to reverse the change in shape without being bound to the molecule