Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biochemistry 304 > CH 11 Carbohydrates P2 > Flashcards

CH 11 Carbohydrates P2 Flashcards

(80 cards)

Start Studying
1
Q

What protects newborns from infection?

A

human milk oligosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many oligosaccharides are there in human milk?

A

150 (amount / comp vary per woman)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Oligosaccharides are carbohydrates that help infants in?

A

protection against bacterial infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What can oligosaccharides prevent the growth of?

A

Streptococcus bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Streptococcus bacteria can be transferred to infant via, and cause?

A

vaginal epithelium

pneumonia, blood poisoning, meningitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Glycoproteins

A

when carbs are linked to proteins
mainly protein by weight
membrane proteins
variety of roles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

3 Main Classes of Glycoproteins

A
  1. Glycoproteins
  2. Proteoglycans
  3. Mucins / Mucoproteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Proteoglycans

A

attached to polysaccharide glycosaminoglycan (make up 95% of this)
mainly carb by weight
structural role, lubricant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Mucins / Mucoproteins

A

characteristically attached by N-acetylgalactosamine.
mainly carb by weight.
Lubricants.
glycoprotein component of mucus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What link carbohydrates to proteins?

A

Asparagine (N-linked) or

Serine / Threonine (O-linked) residues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In all glycoproteins carbs are attached to which atoms?

A

N in side chain asparagine (N-linkage)

O in side chain of serine / threonine (O-linkage)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

All N-linked polysaccharides have a common?

A

pentasaccharide core

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A pentasaccharide core consists of?

A

3 mannoses

2 N-acetylglucosamine units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Glycosidic bonds occur btw?

A

proteins and carbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Glycosidic Bond

A

links carb to side chain of asparagine (N-linked) or side chain of serine / threonine (O-linked)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Erythropoietin

A 
glycoprotein
vital hormone
40% carb by weight
secreted by kidney into blood
stimulates prod of RBC's
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Glycosylation of Erythropoietin enhances?

A

stability of protein in the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the oligosaccharides linked to in Erythropoietin?

A

3 asparagine residues

1 serine residue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Glycosylation functions in?

A

nutrient sensing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

N-acetylglucosamine (GlcNAc) attaches to which residues via which enzyme?

A

serine / threonine

GlcNAc transferase or GlcNAcase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

GlcNAc

A

modifies protein

attached to protein when nutrients are abundant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

GlcNAcase

A

reversible
removes carb
improper reg –> pathological cond’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Glycosaminoglycans

A 
repeating units of disaccharide
1 derivative of amino sugar
1 carries ( - ) charge as carboxylate / sulfate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Proteoglycans are key components of?

A

ECM

lubricants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Mucopolysaccharidoses (ex Hurler Disease)
pathological cond's | result from inability to degrade proteoglycans
26
Hurler Disease
glycosaminoglycans cannot be degraded excess stored in soft tissue of facial regions wide nostrils, depressed nasal bridge, thick lips / earlobes / irregular teeth.
27
Proteoglycans are important components of?
cartilage
28
Cartilage
proteoglycan aggrecan and protein collagen
29
What cushions joints by releasing water on impact and then rebinding water?
glycosaminoglycan component of aggrecan
30
Proteoglycan structure from cartilage is?
proteoglycan monomers emerge laterally at reg intervals from opp sides of central filament hyaluronate
31
Chitin
glycosaminoglycan in insects wings in insects, crustaceans, arachnids exoskeleton
32
What is the most abundant carbohydrate in the world?
chitin
33
The protein component in mucin are?
extensively glycosylated to serine / threonine residues w/ 1st carb N-acetylgalactosamin
34
Region: VNTR - Variable Number Tandem Repeats
site of glycosylation highly glycosylated - forces molecule into extended conformation region of protein backbone rich in serines / threonines.
35
Functions of Mucins
1. lubricants, adhere to epithelial cells - protective barrier. 2. overproduced in cond's - bronchitis, cystic fibrosis, adenocarcinomas (cancer of glandular cells - epithelial origin)
36
Where is the VNTR located?
mucin btw Cys rich domains
37
Cys-rich Domain and D domain
in mucin | facilitate polymerization of many molecules
38
Processed Chitin
carrier - assist in drug delivery (surgical stiches) component of personal care products, additive in food products.
39
Chitin to Chitosan
water soluble to insoluble. demineralization. treat w/ protease to remove proteins.
40
Depigmentation of Chitin
dissolve carotenoids. | deacylated.
41
Protein glycosylation takes place where?
lumen of ER. | Golgi complex.
42
N-linked glycosylation begins in the _____ and continues into the _____.
ER. | Golgi complex.
43
O-linked glycosylation takes place in the?
Golgi complex
44
Golgi Complex
sorting center for proteins (various fates)
45
Dolichol Phosphate
isoprene derivative. | carries lg oligosaccharides - attach to Asp.
46
Enzymes responsible for oligosaccharide assembly are?
glycosyltransferases
47
Glycosyltransferases
catalyze formation of glycosidic bonds
48
Monosaccharide substrates for glycosyltransferases are activated by?
attachment to uridine diphosphate (UDP)
49
Blood groups are based on?
glycosylation patterns
50
Human ABO Blood Groups
reflect specificity of glycosyltransferases
51
All blood groups share?
oligosaccharide foundation: O
52
A form
created when N-acetylgalactosamine added to O by specific glycosyltransferase
53
B form
created when galactose added by another transferase
54
Blood Type: O
lack both enzymes
55
Blood Type: AB
express both enzymes
56
Blood Type A or B:
express only one enzyme | one capable of creating that oligosaccharide
57
I-cell Disease (Mucolipidosis II)
lysosomal enzymes secreted into blood rather than to lysosome
58
I-cell disease results in?
mutation. disrupts digestion process in lysosomes. lysosomes have lg inclusions of undigested glycosaminoglycans and glycolipids. carb doesn't direct key enzymes to lysosome, not synthesized properly.
59
What happens to the digestive enzymes in I-cell Disease?
synthesized. | sent to blood / urine.
60
Patients w/ I-cell Disease lack the ability to?
phosphorylate mannose to create mannose 6-phosphate
61
How are oligosaccharides seq'd?
enzymes that cleave specific glycosidic bonds
62
MALDI-TOF - Oligosaccharides
used to identify released sugars
63
Lectins
specific carb-binding proteins.
64
Lectins are a particular class of?
glycan-binding proteins specific to oligosaccharides on cell surface
65
Lectin Classes
C-type | L-Lectins
66
C-type Lectins
Ca2+ ion facilitates interaction btw protein and carb
67
Selectins
member of C-type Lectin. bind immune-system cells to sites of injury. inflammatory response.
68
L-Selectine
member of C-type Lectin. | allow attachment of embryo to uterus.
69
L-Lectin
chaperones (assist in protein folding). in eukaryotic ER. some in potent insectisides.
70
Influenza Virus
binds to sialic acid residues.
71
How do many pathogens gain entry into cells?
binding to carbs on cell surface
72
Influenza Virus Process
1. recognizes sialic acid residues linked to galactose residues on cell surface of glycoproteins. 2. viral protein hemagglutinin (lectin) binds to sugars.
73
How does Influenza spread?
when viral protein neuraminidase (sialidase) cleaves glycosidic bonds btw sialic acids residues and rest of cellular glycoprotein. frees virus to infect new cells.
74
Neuraminidase Inhibitors
Tamiflu | Relenza
75
Plasmodium Falciparum
parasitic protozoan. causes malaria. relies on glycan binding to infect, colonize host.
76
𝛂-Glucosidase (Maltase) Inhibitors
help maintain blood glucose homeostasis. | medications exist to inhibit this enzyme.
77
Hyperglycemia
advanced glycation product. type 1 diabetes (absent insulin). type 2 diabetes (ineffective insulin)
78
Glycogen Digestion and Starch
degradation into smaller oligosaccharides by α-amylase. | further digested by α-glucosidase.
79
α-amylase
secreted by salivary glands and pancreas
80
Competitive inhibitors of the enzyme α-glucosidase are?
acarbose and miglitol. | taken at meal start to reduce post-meal glucose absorption in type 2 diabetes.

Biochemistry 304 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions