Unit 3: Carbohydrates (Part 1) Flashcards
(145 cards)
1
Q
Carbohydrates are primary source of _______ for brain, erythrocytes, and retinal cells in humans
A
energy
2
Q
T/F: Nervous tissue can concentrate/ store carbohydrates
A
FALSE
3
Q
T/F: Glucose can cross the BBB
A
TRUE
4
Q
T/F: RBC can produce glucose
A
FALSE
5
Q
What is the role of glucose to RBC?
A
Maintains a healthy RBC and free from oxidative stress
6
Q
Carbohydrates is the major food source and energy supply for the body and stored primarily as ________ in the ________ and _____________
A
Glycogen; Liver; Muscles
7
Q
Carbohydrates is involved in two disease states:
A
Hyperglycemia and Hypoglycemia
8
Q
Carbohydrates is important for the diagnosis of?
A
Diabetes mellitus
9
Q
Carbohydrates are substances containing these 3 elements:
A
Carbon, Hydrogen, Oxygen
10
Q
There is 1 _________ per carbon
A
Water
11
Q
All carbohydrates contain these two functional groups:
A
Carbonyl (C=O) and Hydroxyl (OH)
12
Q
Carbohydrates are hydrates of ____________ because they contain _________
A
Carbon; Water
13
Q
Carbohydrates can be classified based on these 4 structural properties:
A
- Size or number of the base carbon chain
- Location of the CO functional group
- Number of sugar units
- Stereochemistry of the compound
14
Q
Based on size or number of base carbon chains, carbohydrates can be classified as:
A
- Trioses (3C)
- Tetroses (4C)
- Pentoses (5C)
- Hexoses (6C)
15
Q
Examples of Pentose:
A
Ribose, Deoxyribose
16
Q
Examples of Hexose:
A
Glucose, Fructose, Galactose
17
Q
Smallest carbohydrate, a three-carbon compound
A
Glyceraldehyde
18
Q
Based on the location of CO functional group, carbohydrates can be classified as:
A
- Aldose
- Ketose
19
Q
In aldoses, the carbonyl group can be found at the:
A
Terminal
20
Q
Functional group of aldose
A
Aldehyde group
21
Q
In ketoses, the carbonyl group can be found at the:
A
Middle
22
Q
Functional group of ketose
A
Ketone group
23
Q
Two carbohydrate models
A
- Fischer projection
- Haworth projection
24
Q
In Fischer projection, the aldehyde or ketone group can be found at:
A
the top
25
In Fischer projection, carbons are numbered starting at the:
Aldehyde or ketone head (at the top)
26
In Haworth projection, the compounds are represented in:
Cyclic form
27
Haworth projection is formed when the functional group reacts with ________ group on the same sugar to form a _______
Alcohol; Ring
28
Based on number of sugar units, carbohydrates can be classified as:
- Monosaccharides
- Disaccharides
- Oligosaccharides
- Polysaccharides
29
This is the simplest sugar, based on the number of units
Monosaccharides
30
T/F: Monosaccharides can be hydrolyzed
FALSE
31
Examples of monosaccharides
- Triose
- Tetrose
- Pentose
- Hexose (Glucose, Fructose, Galactose)
32
____________ are two monosaccharide units linked by ______________
Disaccharides: Glycosidic bonds
33
When two monosaccharides are joined together, water is ______________
released
34
If we want to split disaccharides, _________ is done
Hydrolysis
35
Water is _________ if disaccharides are split
consumed
36
Maltose is composed of these two monosaccharides
2 D-glucose units
37
Lactose is composed of these two monosaccharides
1 unit of glucose + 1 unit of galactose
38
Sucrose is composed of these two monosaccharides
1 unit of glucose + 1 unit of fructose
39
Sucrose is also known as:
Common table sugar
40
Lactose can be found in:
Milk
41
Oligosaccharides have ________ sugar units
3-10 sugar units
42
T/F: Oligosaccharides have few sugar units, composed of more than 10 sugar units.
FALSE, while it is true that it is composed of few sugar units. It is only composed of 3-10 sugar units.
43
Polysaccharides have ______ sugar units
More than 10 sugar units
44
Examples of Polysaccharides:
Glycogen and Starch
45
T/F: Central carbons of a carbohydrate are asymmetric
TRUE
46
This allows for spatial arrangement in the molecules
Chirality
47
This is the spatial arrangement in the molecules
Stereoisomers (Enantiomers)
48
Enantiomers are identified by:
Hydroxyl group
49
Enantiomers cannot be overlapped or ______________
Non-superimposable
50
Most sugars in humans are in which enantiomeric form?
D-form
51
Stereoisomers have the same:
Order and types of bonds
52
Stereoisomers have different:
Spatial arrangement and properties
53
If the OH group is found on the right of Fischer projection, it is a:
D-isomer
54
If the OH group is found on the left of Fischer projection, it is a:
L-isomer
55
Most ingested carbohydrates:
Polymers: Starch and Glycogen
56
Digestion starts here
Mouth
57
This enzyme is essential for digestion, and is produced by the salivary gland:
Salivary amylase
58
Starch is broken down into these two units with the help of amylase:
Disaccharide and Dextrin
59
_________ stops the action of amylase
Gastric juices
60
T/F: Amylase is useful for the breakdown of carbohydrates
FALSE
61
Around _____ of the starch has broken down once it enters the stomach
30%
62
This enzyme help dissolve the solid food and break down carbohydrates into monosaccharides in the small intestine:
Pancreatic amylase
63
_____________ is released by the ___________ which further hydrolyze or break down polymers
Maltase; intestinal mucosa
64
_____________ is derived from the ____ which hydrolyzes sucrose to _________ and ___________
Sucrase; gut; Glucose and Fructose
65
_____________ is derived from the ____ which hydrolyzes lactose to _________ and ___________
Lactase; gut; Glucose and Galactose
66
Three essential digestive organs important for carbohydrate digestion:
Mouth, Intestines, Liver
67
This is the only carbohydrate that can be directly used for energy or storage
Glucose
68
T/F: Polysaccharides and disaccharides can be absorbed by the gut, stored in the liver, and enter the blood stream.
FALSE, they have to be converted to monosaccharides first
69
3 Pathways of Glucose Metabolism
- Embden Meyerhof (Parnas) Pathway
- Hexose Monophosphate Shunt (Pentose pathway shunt)
- Glycogenesis
70
The ultimate goal of the cells where this pathway/shunt are happening is for it to be converted to _______ and ________
Carbon dioxide and Water
71
During glucose metabolism, the cells obtains _______
ATP
72
In the Embden Meyerhof Parnas Pathway, glucose is broken down into _______________
2 molecules of pyruvate
73
10 steps of Glycolysis
1. Glucose
2. Glucose 6-phosphate
3. Fructose 6-phosphate
4. Fructose 1,6-bisphosphate
5. Glyceraldehyde 3-phosphate
6. 1,3-bisphosphoglycerate
7. 3-phosphoglycerate
8. 2-phosphoglycerate
9. Phosphoenolpyruvate
10. Pyruvate
74
Anaerobic glycolysis occurs in the:
Cytosol
75
The aerobic pathway occurs at the
Mitochondria
76
What is the conversion of other substrates to glucose
Gluconeogenesis
77
Other substrates that can be used for gluconeogenesis:
- Lipids
- Fatty acids
- Ketones
78
For Embden Meyerhof Parnas Pathway:
- ATP used
- ATP produced
- Net ATP
- 2 used
- 4 produced
- 2 net ATP
79
This is the detour of glucose-6-phosphate from the glycolytic pathway
Hexose Monophosphate Shunt
80
After going through the Hexose Monophosphate Shunt, glucose 6-phosphate becomes:
6-phosphogluconate (6-phosphogluconic acid)
81
T/F: There is ATP production in Hexose Monophosphate Shunt
FALSE
82
This is the pre-cursor of products used for biosynthetic reactions
6-phosphogluconate
83
These are the byproducts of Hexose Monophosphate Shunt:
- NADPH
- 2G-SH
- Ribose
84
This has a reducing power; without this the cell membrane would easily be destroyed, eventually leading to cell death
NADPH
85
This is an anti-oxidant which prevents oxidative stress from the action of free radicals
2G-SH (Glutathione disulfide)
86
Disease wherein glucose 6-phosphate is not converted to 6-phosphoglycerate
G6PD deficiency
87
This pathway is used only when the body's energy requirements are being met
Glycogenesis pathway
88
This enzyme is important for the conversion of glucose to glycogen
Glycogen synthase
89
This enzyme is important for converting glycogen to glucose
Glucose 6-phosphatase
90
This is the process of reverting glycogen back into glucose
Glycogenolysis
91
T/F: Glycogenolysis can occur in sites other than the liver like the muscles.
FALSE, it can only occur in the liver
92
This is the reason why Glycogenolysis can only occur in the liver
Glucose 6-phosphatase
93
For brief fasting, which process can occur?
Glycogenolysis
94
For fasting more than 24 hours, this process can occur:
Gluconeogenesis
95
Metabolism of glucose molecule to pyruvate or lactate for production of energy
Glycolysis
96
Formation of glucose-6-phosphate from noncarbohydrate sources
Gluconeogenesis
97
Breakdown of glycogen to glucose for use as energy
Glycogenolysis
98
Conversion of glucose to glycogen for storage
Glycogenesis
99
Conversion of carbohydrates to fatty acids
Lipogenesis
100
Decomposition of fat
Lipolysis
101
Organs involved in carbohydrate metabolism:
- Liver
- Pancreas
- Other endocrine glands
102
Major hormones involved in carbohydrate metabolism:
- Insulin
- Glucagon
103
Other hormones involved in carbohydrate metabolism
- Somatostatin
- Epinephrine
- Cortisol
- Thyroxine
- Growth hormone
104
Insulin is produced by the _______ cells of the ____________ in the _____________
Beta; islets of Langerhans; pancreas
105
This is the primary hormone responsible for the entry of glucose into the cell
Insulin
106
Insulin is a ______ agent
Hypoglycemic
107
Glucagon is produced by the ________ cells of the __________ in the _________
Alpha; islets of Langerhans; pancreas
108
This is released during stress and fasting states; and is a hyperglycemic agent
Glucagon
109
Somatostatin is produced by the _______ cells of the _________ in the _______
Delta; islets of Langerhans; pancreas
110
Somatostatin is also known as
Growth Hormone Inhibiting Hormone (GHIH)
111
Somatostatin _______ plasma glucose
Increases
112
This regulates insulin and glucagon
Somatostatin
113
Epinephrine is produced by the ________
Adrenal medulla
114
Epinephrine __________ blood glucose
Increases
115
Epinephrine:
__________ insulin
__________ glycogenolysis
__________ lipolysis
- Inhibits
- Increases
- Promotes
116
Epinephrine is released in times of _______
Stress
117
Cortisol is produced by the ____________ (specific)
Adrenal cortex in the Zona fasiculata
118
Cortisol is stimulated by which hormone?
Adrenocorticotropic hormone (ACTH)
119
RELATIONSHIP:
_____ cortisol = increased plasma glucose
High
120
How is glucose increased by cortisol?
When the cortisol levels decreased, the pituitary glands release ACTH, which stimulates cortisol (increasing it), thus increasing glucose
121
Cortisol:
________ intestinal entry of glucose into the cell
________ gluconeogenesis, lipolysis, glycogenolysis
- Decrease
- Increase
122
Thyroxine is produced from the _______________
Thyroid gland
123
The release of Thyroxine is stimulated by?
Thyroid Stimulating Hormone (TSH)
124
Thyroxine _________ plasma glucose
Increases
125
Thyroxine _________ glycogenolysis, gluconeogenesis, intestinal absorption of glucose
Increases
126
Growth hormone is from __________________
Anterior pituitary gland
127
Growth hormone _____________ plasma glucose
Increases
128
Growth hormone:
___________ entry of glucose into the cells
___________ glycolysis
- Decreases
- Increases
129
What stimulates growth hormone?
Low glucose levels
130
This disease is characterized with high cortisol levels
Cushing's syndrome
131
This disease is characterized with low cortisol levels
Addison's disease
132
In hyperglycemia, blood sugar is _____________________ when fasting
Higher than 100 mg/dL
133
For non-fasting, _________ mg/dL is considered hyperglycemic
140 mg/dL
134
T/F: Hyperglycemia typically occurs before meal
FALSE, after meal
135
In diabetics, hyperglycemia occurs when the cells of the body are less responsive to insulin. What type of diabetes?
Type 2 diabetes
136
In diabetics, hyperglycemia occurs if there is lack of insulin in the blood stream. What type of diabetes?
Type 1 diabetes
137
T/F: In hyperglycemia, the link between hyperglycemia and seizures is clear.
FALSE, it is not clear, still debatable
138
In hypoglycemia, blood sugar is ___________________ when fasting
lower than 50 mg/dL
139
Hypoglycemia typically occurs ______ meal.
Before
140
T/F: Hypoglycemia can also occur after meal if one had a gastric bypass surgery.
TRUE
141
This can occur if the body produces too much insulin (higher than body needs) after meal.
Postprandial hypoglycemia
142
T/F: Hypoglycemia occurs when insulin is injected in right amounts.
FALSE; more than
143
T/F: It's clear that hypoglycemia can be one of trigger factors of seizures
TRUE
144
Laboratory findings in Hyperglycemia:
_________ glucose in plasma and urine
_________ urine specific gravity
_________ serum and urine osmolality
Increased
145
Laboratory findings in Hyperglycemia:
________ found in serum and urine (_______ and _______)
________ blood and urine pH (_________)
________ of electrolytes
- Ketones; Ketonemia; Ketonuria
- Decreased; acidosis
- Imbalance
