Carbohydrates (Section 1)

Question 1

How many kcal/g of CHO?

Answer 1

4

Question 2

Approximately how much of the human diet comes from CHO?

Answer 2

50-60%

Question 3

Of all the CHO consumed in the human diet how much is simple carbs & how much is complex?

Answer 3

50% / 50%

Question 4

What are the 3 monosaccharides?

Answer 4

Glucose
Fructose
Galactose

Question 5

What are the 3 Disaccharides?

Answer 5

Sucrose
Lactose
Maltose

Question 6

What are the 3 Polysaccharides?

Answer 6

Starch (amylose, amylopectin)
Cellulose
Glycogen

Question 7

Sucrose is made of units of?

Answer 7

Fructose & Glucose

Question 8

Lactose is made of units of?

Answer 8

Galactose & Glucose

Question 9

Maltose is made of units of?

Answer 9

Glucose & Glucose

(x2 units of glucose)

Question 10

Ribose is a ___ Carbon chain molecule and is found where?

Answer 10

5Carbon - found in DNA/RNA

Question 11

What are Oligosaccharides & what are they made up of?

Answer 11

Complex CHO made of combinations of glucose, galactose, and fructose.

Question 12

What makes Oligosaccharides unique compared to other simple or complex CHO?

Answer 12

Digested by bacteria in the gut (fermentation)

Question 13

Polysaccharides contain which types of glycosidic bonds how are the structured?

Answer 13

a1-4 - Linear
a1-6 - Branched
b1-4 - Linear

Question 14

Amylose (starch) makes up approximately how much of the polysaccharides found in the body?

Answer 14

15-20%

Question 15

What enzyme opens the a1-4 bound found in Amylose?

Answer 15

Amylase

Question 16

Amylopectin is different from Amylose in through what primary function?

Answer 16

It is manufactured with the intent of conserving storage space.

Question 17

Amylopectin accounts for roughly how much of the polysaccharides found in the body?

Answer 17

80-85%

Question 18

Amylopectin contains which two glycosidic bonds and what are the enzymes that open each one?

Answer 18

a1-4 bond (Amylase)
a1-6 bond (Isomaltase)

Question 19

Glycogen is known as the ______ form of polysaccharides in animals?

Answer 19

Storage

Question 20

Why does Cellulose (polysaccharide) goes largely unabsorbed?

Answer 20

It’s bonds (b1-4) are resistant to human enzymes and is utilized by bacteria in the fermentation process.

Question 21

What sugar is the only sugar to get absorbed via “facilitated diffusion”

Answer 21

Fructose

Question 22

Fructose is absorbed faster or slower than glucose?

Answer 22

Slower

Question 23

Fructose absorption can be enhanced when combined with?

Answer 23

Glucose and/or Galactose

Question 24

Glucose enters other cells via facilitated diffusion by the action of what hormone?

Answer 24

Insulin

(skips portal circulation & goes straight to cellular uptake)

Question 25

Which sugars are taken up by liver cells freely through portal circulation & what form do they enter downstream metabolic pathways?

Answer 25

Galactose & Fructose > Enter metabolic pathways as a glucose derivative.

Question 26

What are the 4 major pathways of CHO Metabolism?

Answer 26

Glycogenesis Glycogenolysis Glycolysis Gluconeogenesis

Question 27

What is the function of Glycogenesis?

Answer 27

Making of Glycogen (from excess glucose)

Question 28

What is the function of Glycogenolysis?

Answer 28

Breakdown of glycogen

Question 29

What is the function of Glycolysis?

Answer 29

Oxidation of glucose into Pyruvate

Question 30

What is the function of Gluconeogenesis?

Answer 30

Production of glucose from noncarbohydrate intermediates

Question 31

What is the function of Hexose Monophosphate Shunt?

Answer 31

Production of 5-carbon monosaccharides and NADPH

Question 32

What is the function of the Tricarboxylic Acid Cycle (TCA) cycle?

Answer 32

Oxidation of pyruvate and acetyle CoA

Question 33

Where does glycogenesis occur?

Answer 33

Liver & Muscle

Question 34

What is the irreversible step of glycogenesis?

Answer 34

Glucose is phosphorylated by ATP (and other substrates) to produce: G-6-P

Question 35

What 2 enzymes are used to kickstart glycogenesis and where do the originate from?

Answer 35

Hexokinase (muscle) Glucokinase (liver)

Question 36

Glycogenolysis as the reverse pathway of Glycogenesis converts what into what?

Answer 36

Glycogen > Glucose

Question 37

In Glycogenolysis, G-1-P is isomerized into what?

Answer 37

G-6-P

Question 38

Glycolysis is the act of converting glucose into what & where does it occur?

Answer 38

Glucose > Pyruvate (occurs in the cytoplasm)

Question 39

What is step 1 of Glycolysis? (Glucose into what?)

Answer 39

Glucose > (enters cell & is phosphorylated) > G-6-P (requires ATP)

Question 40

What is step 2 of Glycolysis? (G-6-P into what?)

Answer 40

G-6-P > (Phosphoglucose Isomerase) > F-6-P

Question 41

What is step 3 of Glycolysis? (F-6-P into what?)

Answer 41

F-6-P > (phosphorylated) > F-1,6-Bisphosphatase Rate Limiting Enzyme: PFK

Question 42

What is step 4 of Glycolysis? (F-1,6-Bisphophatase into what?

Answer 42

F-1,6-Bisphphatase > (cleaved: aldolase) > G3-P

Question 43

What is step 5 of Glycolysis? (G3-P into what?)

Answer 43

G3-P > (phosphorylated: G3-P Dehydrogenase) > PEP

Question 44

In the final steps of Glycolysis, ADP is phosphyorylated into what and yields what?

Answer 44

ADP > ATP ; yields Pyruvate