Clinical Chemistry: Carbohydrates

Front 1

Functions of Carbohydrates

Back 1

1) short term energy storage, sugars for immediate use

2) dietary fiber

3) blood group antigens

4) lubrication/connective tissue

5)cytoskeleton (proteoglycan/GAGs)

6) Cell surface receptors (glycoproteins)

7)hormones

Front 2

How much glucose does the average person need per day?

Back 2

190 g

Front 3

How much glucose does the brain use each day?

Back 3

150 g

Front 4

True or False: All cell types contain all of the enzymes required for the complete metabolism of sugars?

Back 4

False

Front 5

What two organs can add glucose to the blood?

Back 5

Liver and Kidney

Front 6

What three elements do all sugars contain?

Back 6

Carbon, hydrogen, and oxygen

Front 7

Name the two most important pentoses

Back 7

Ribose and deoxyribose

Front 8

True or false: All human sugars are D-.

Back 8

True

Front 9

True or false: Epimers differ in orientation at two different carbons in a sugar molecule.

Back 9

False

Front 10

Name 3 monosaccharides

Back 10

glucose, fructose, and galactose

Front 11

name three disaccharides

Back 11

maltose, sucrose, lactose

Front 12

True or false: Blood group antigens and transferrin are oligosaccarides.

Back 12

True

Front 13

True or false: Starch, cellulose, glycogen, and glycosaminoglycans (GAGs) are all polysaccharides.

Back 13

True

Front 14

An anomeric carbon refers to the ____________ carbon in a ring?

Back 14

first

Front 15

Why is sucrose a non-reducing sugar?

Back 15

The ester linkage that binds it is too stable to be reduced.

Front 16

Name two reducing disaccharides

Back 16

Maltose, lactose

Front 17

What is the linkage for maltose?

Back 17

Glucose a(1,4) Glucose

Front 18

What is the linkage for lactose?

Back 18

Galactose B(1,4) glucose

Front 19

True or false: An alpha linkage creates a flat molecule.

Back 19

False; beta linkages are flat.

Front 20

What functional group is required for a sugar to be reducing?

Back 20

Carboxylic acid

Front 21

True or false: All monosaccharides are reducing sugars.

Back 21

True

Front 22

What type of sugar is not built on a template?

Back 22

Polysaccharides

Front 23

What are the three things that the length of a polysaccharide is based on?

Back 23

What tissue it's in, the nutritional state of the person, and the presence or absence of disease

Front 24

_____________ are polysaccharides containing only one type of monosaccharide.

Back 24

Homopolysaccharides

Front 25

Name three homopolysaccharides

Back 25

Glycogen, starch, and cellulose (All three contain exclusively glucose)

Front 26

____________ are polysaccharides that contain repeating disaccharide chains

Back 26

Heteropolysaccharides

Front 27

Name a type of heteropolysaccharide

Back 27

Glucosaminoglycans (GAGs)

Front 28

True or false: Glycogen is the most abundant polysaccharide on earth.

Back 28

False; cellulose

Front 29

Name 2 benefits of dietary fiber.

Back 29

1) Aids in the absorption of water to make feces travel faster and more smoothly through the gut.
2) Aids in the absorption of nutrients.

Front 30

Name the linkage for cellulose

Back 30

Glucose B (1,4) Glucose...etc.; no branching

Front 31

Name the linkage for glycogen

Back 31

Glucose a(1,4) Glucose; branch points at a(1,6) linkages

Front 32

__________ is the major storage form of carbohydrate for humans.

Back 32

Glycogen

Front 33

Name the linkage for starch

Back 33

**Amylose/Amylopectin, with a(1,4) linkages and a(1,6) branch points

**Amylose/amylopectin are made of glucose sub-units.

Front 34

Glycosaminoglycans (GAGs) are comprised of a _____ _____ subunit and a ____________ ________ subunit.

Back 34

Uronic acid and Modified sugar

Front 35

True or false: Glycosaminoglycans have branches.

Back 35

False

Front 36

What are the most abundant heteropolysaccharides in the body?

Back 36

Glycosaminoglycans (GAGs)

Front 37

Glycosaminoglycans are an important part of joints because they are _____ ____ and ____ ______.

Back 37

Excellent lubricants and shock absorbants.

Front 38

Name an important proteoglycan

Back 38

Collagen (holds connective tissues together)

Front 39

What are three fates of proteoglycans?

Back 39

1) secreted into the extracellular matrix where they provide stability and organization

2) stored in secretory granules where they attract positively charged secretory components

3) inserted into cell membrane via core proteins

Front 40

True or False: Proteoglycans are all very similar, having similar core proteins and varying little in their sizes throughout the body.

Back 40

False; highly variable and large number of core proteins

Front 41

Glycoproteins are comprised of a core protein and attached to a ___________________________.

Back 41

Short, branched oligosaccharide chain

Front 42

Glycoproteins are generally used for ___________ and ___________.

Back 42

Cell signaling and cell recognition

Front 43

Name three functions of Glycoproteins

Back 43

1)hormones
2)blood group antigens
3) enzymes

Front 44

Glycoproteins are structural components of __________ and ____________.

Back 44

Extracellular matrix, mucus secretions

Front 45

Name a glycoprotein

Back 45

Transferrin

Front 46

True or false: lysosomal enzymes are glycoproteins

Back 46

True

Front 47

In what system of the body are glycolipids important?

Back 47

The nervous system

Front 48

Joining two monomers requires ________.

Back 48

Energy

Front 49

The process of adding sugar to a molecule is called ______________.

Back 49

Glycosylation

Front 50

True or false: Glucose can be modified into all other sugars, so it is a dietary essential.

Back 50

True

Front 51

Name the disease: Connective tissue disorder characterized by a genetic mutation that causes misfolded fibrillin. Symptoms are highly variable, but individuals are very tall, thin, and loose jointed. The most common cause of death is aortic dissection leading to rupture of a the wall of a heart valve.

Back 51

Marfan Syndrome

Front 52

Amylase can break a(1,4) bonds in what three sugars?

Back 52

Amylose, trisaccharides, and amylopectins

Front 53

What is the difference between salivary amylase and pancreatic amylase?

Back 53

Salivary amylase can withstand the harsh pH of the stomach while pancreatic amylase was designed to work in the milder pH intestines.

Front 54

Where do endoglycosdisases cut sugars?

Back 54

Randomly in the middle

Front 55

What four enzymes break down starch?

Back 55

1)Sucrase-isomaltase complex
2) Glucoamylase complex
3) Lactase (B-galactosidase) Complex
4) Trehalase Complex (For algae, fungi etc)

Front 56

What are the two transport mechanisms responsible for the entry of sugars across the mucosal cell membrane?

Back 56

1) Facilitative transporters for glucose and fructose
2) Na+ dependent co-transporters for glucose and galactose

**The proteins that carry out these mechanisms are in the lumen of the gut.

Front 57

True or false: Sugars are non-polar.

Back 57

False

Front 58

When brush border enzymes to degrade a sugar are missing, a person is said to be _____________ of that sugar.

Back 58

Intolerant

Front 59

What is the difference between primary and secondary lactose intolerance?

Back 59

Primary lactose intolerance is a genetic defect, while secondary is a result of damage to the intestinal villi.

Front 60

Why do most people survive lactose intolerance?

Back 60

They are able to easily avoid anything in their diet that includes milk sugars.

Front 61

What gas do the enteric bacteria produce when they have the substrates and energy required from carbohydrate fibers?

Back 61

H2

Front 62

Pectins bind to ___________ in order to reduce blood cholesterol.

Back 62

Bile acids

Front 63

What is the name of the seaweed fiber that is a common additive to salad dressings and a large component of the now defunct McLean burger?

Back 63

Carageenan

Front 64

What four sugars can the CliniTest urine test for?

Back 64

Glucose, galactose, lactose and fructose

Front 65

Who would you do a CliniTest on?

Back 65

Usually only a baby that you suspect of having a congenital sugar metabolism disorder. These tests are limited and there is a long waiting period to get more.

Front 66

What sugar is the ChemStrip urine test for?

Back 66

Glucose

Front 67

When will glucose spill into the urine?

Back 67

1) when the plasma concentration exceeds 180 mg/dl
2) at lower concentration in a patient with renal tubular damage.

Front 68

What are the three plasma glucose measurement tests?

Back 68

1) Glucose Oxidase with Peroxide
2) Hexokinase with G6PDH
3) Glucose Oxidase with O2 Consumption

Front 69

What is the difference between plasma glucose (from the vein) and capillary blood glucose?

Back 69

Capillary blood glucose has already deposited some glucose in the tissues, so it is 10-15% lower than plasma glucose.

Front 70

What is the normal range for plasma glucose?

Back 70

70-99 mg/dl

Front 71

What happens when your PG (Plasma Glucose) level drops below 45 mg/dl?

Back 71

Autonomic nervous system function declines (breathing and heartrate)

Front 72

What happens when your PG (Plasma Glucose) level drops below 25 mg/dl?

Back 72

Central Nervous System function declines (higher thought processes), leads to shock/coma

Front 73

What happens when your plasma glucose exceeds 600 mg/dl?

Back 73

Coma

Front 74

What are some common symptoms of Hypoglycemia?

Back 74

Tiredness, Confusion, Hunger, Weakness, Dizziness, Loss of concentration, Heart palpitations

Front 75

What are some common symptoms of Hyperglycemia?

Back 75

Thirstiness, Frequent Urination, Dehydration, Dizziness, Excessive appetite but weight loss, vomiting, abdominal pain

Front 76

What is the conversion factor to convert serum glucose level to CSF glucose?

Back 76

(Serum Glucose Level) x 0.6= CSF glucose

Front 77

What does low CSF glucose indicate?

Back 77

Meningitis.

Front 78

What does low CSF glucose + increased protein concentration indicate?

Back 78

Bacterial meningitis.

Front 79

What does a high CSF glucose indicate?

Back 79

Hyperglycemia

Front 80

What is the metabolic disorder characterized by chronic hyperglycemia with disturbances in carbohydrate, protein, and fat metabolism?

Back 80

Diabetes Mellitus

Front 81

What causes Diabetes Mellitus?

Back 81

Defect in insulin production, secretion, action, or a combination of those

Front 82

What is the difference between Type 1 and Type 2 Diabetes Mellitus?

Back 82

Type 1- Autoimmune destruction of pancreatic cells
Type 2- Many causes, esp. obesity