Carbohydrates

Question 1

What are carbs

Answer 1

These are very important sources and stores of energy and are components of large complex molecules, including DNA and RNA. Recognition events in protein folding and cellular interaction and acquired and inherited metabolic disorders affect health.

Question 2

What are the three different types of carbs?

Answer 2

Monosaccharides, the simplest

• Disaccharides, two monosaccharides
• Polysaccharides, many monosaccharides

Question 3

What makes up a monosaccharides units ?

Answer 3

consists of 3-6 carbon atoms, a carbonyl group (aldehyde or ketone) and several hydroxide groups.

Question 4

What are the two types of monosacchrides

Answer 4

Aldoses are monosaccharides with an aldehyde group at the end of the chain and many hydroxyl groups
Ketoses are monosaccharides with a ketone group and many hydroxyl groups (fructose)(e.g. keto(has ketone group)hexose(six carbons))

Question 5

What is a Fischer projection?

Answer 5

• This is used to represent carbohydrates
• Places the most oxidized group at the top
• Shows chiral carbons as the intersection of vertical and horizontal lines

Question 6

What determines an L or D isomer?

Answer 6

n a fischer projection the -OH group on the chiral carbon furthest away from the carbonyl group determines an L or D isomer
Left = L
Right = D

Question 7

Where is D-Glucose found?

Answer 7

fruits and honey

Question 8

GALACTOSEMIA

Answer 8

• Lack of the enzyme required for galactose metabolism
• Can result in accumulation of galactose intermediates
• Toxic effects in liver, brain, kidneys and eyes
  Sample of blood is taken as a prick of the childs heel.

Question 9

Cyclic structures

Answer 9

These are a prevalent form of monosaccharides with 5 or 6 carbon atoms. They form when the hydroxyl group on the C-5 reacts with the aldehyde group or ketone group. Basically remember c5 reacts with the main group

Question 10

What are the steps in creating cyclic structures?

Answer 10

STEP 1 Number the carbon chain and turn clockwise to form a linear open chain
STEP 2 Bond the C5 – o – to C1, place the C6 group above the ring, write the OH groups on C2 and C4 below the ring. Write the OH group on the C3 above the ring and write a new OH on C1.
STEP 3 write the new OH on C1 (down for alpha form and up for beta form.)

Question 11

Whar are the names in relation to the number of carbon

Answer 11

Triose = 3 c atoms
Tetrose = 4 c atoms
Pentose = 5 c atoms
Hexose = 6 c atoms

Question 12

During hypoglycaemia, the glucose forms a covalent bond with a red blood cell, what is the resulting structure known as

Answer 12

Hb1Ac

Question 13

How do we get for sugars?

Answer 13

Reducing sugars - a sugar that will reduce organic ions such as Cu++ (Fehlings agent)
ALL MONOSACCHARIDES ARE REDUCING SUGARS

Question 14

Defects in carbohydrate metabolism

Answer 14

diabetic ketoacidosis, hyperosmolar coma, and hypoglycemia, all affect the central nervous system

Question 15

role of glycogen

Answer 15

storage form of glucose, acts as an energy store