Day 1.1.1 Flashcards
(480 cards)
1
Q
Cingulum aka
A
Linguocervical ridge
2
Q
What is the cingulum
A
Lingual lobe of an anterior tooth
3
Q
Where is cingulum located
A
It makes up the bulk of the cervical third of the lingual surface
4
Q
Teeth with centrally located cingulum
A
- Maxillary Lateral incisor
- Maxillary Canine
- Mandibular central incisor
5
Q
Tooth numbers of teeth with centrally located cingulum
A
6, 7, 10, 11, 24, 25.
6
Q
Teeth with cingulum located off-centre to the distal
A
- Maxillary Central Incisor
- Mandibular Lateral Incisor
- Mandibular Canine
7
Q
Total number of cingula in each dentition
A
12
8
Q
Characteristics common to all mandibular anteriors
A
- Indistinct Cingula
- Smooth lingual anatomy
- No lingual grooves or pits
- Incisal edges lingual to root axis line
- Facial convexity - continuous incisoapically
9
Q
Which anterior teeth have a continuous convexity from incisal edge to apex?
A
Mandibular anteriors
10
Q
How many teeth do mandibular central incisors occlude with?
A
One - Maxillary central incisor
11
Q
In how many planes is the occlusion of mandibular central incisors measured?
A
Three -
- Centric
- Protrusive
- Lateral protrusive
12
Q
On which aspect of the central incisors is the alveolar process thinnest?
A
Facial
13
Q
Is local infiltration effective for anaesthetising central incisors? Why (not)?
A
Yes, because of the thinness of the alveolar process facial to the central incisors
14
Q
Which teeth in the mouth exhibit labial ridges?
A
Canines (lower and upper)
6, 11, 22, 27.
15
Q
Which proximal aspect of the anterior teeth shows greater CEJ curvature?
A
Mesial.
16
Q
What is the most reliable way to distinguish between mandibular central and lateral incisor?
A
In facial view, the mandibular lateral incisor (23, 26) crown tips slightly to the distal relative to the root.
17
Q
Between 24 and 23, whose crown is larger mesiodistally?
A
23
18
Q
Between 25 and 23, which one is more bilaterally symmetrical?
A
25
19
Q
On which one out of 26 and 24 is the cingulum placed slightly distal to the centre?
A
26
20
Q
In 24, which marginal ridge is longer?
A
Neither. They are the same length.
21
Q
In 23, is the mesial marginal ridge shorter than the distal marginal ridge?
A
No. Vice versa.
22
Q
Are all proximal contacts at the same level for mandibular incisors?
A
No. 23 and 26 have distal proximal contacts more apical than mesial contacts.
24 and 25 have contacts at the same level
23
Q
Among all the mandibular incisors, which proximal contact is the most apical?
A
Laterals (23, 26)
24
Q
Which incisal angles are the most rounded in mandibular incisors?
A
Distoincisal angles of laterals
25
Between the lingual and facial cervical lines of mandibular incisors, which one is positioned more apically?
Lingual
26
What is the shape of the proximal aspects of anterior teeth?
Triangle
27
Name all triangular aspects in the oral cavity
All anterior teeth - proximal aspects
28
Name all rhomboids in the oral cavity
Mandibular posteriors - proximal aspects
29
Name all Trapezoids with their longest side on the occlusal, in the oral cavity
All anteriors - facial aspect
| All posteriors - facial aspect
30
Name all trapezoids with their shortest side occlusal, in the oral cavity
All maxillary posteriors - proximal aspects
31
What is the basic shape of the cross section of the pulp canal in mandibular incisors?
Elliptical
32
Which one has a larger root, 24 or 23?
23 (in all dimensions)
33
Which incisal edge is straighter, 25 or 23?
25
34
Which part of the incisal edge is curved on 23 and 26?
Distal
35
What is different about the incisal edge of the mandibular lateral when compared to the mandibular central?
It is slightly curved and rotated on the distal
36
which is the only anterior tooth in which distoincisal angle is as sharp as mesioincisal angle?
mandibular central incisor
37
What speech sounds do anterior teeth play a role in
v
f
th
38
What is the axial inclination of the anterior teeth when viewed from the sagittal plane
facially inclined
39
which aspects of incisors have proximal contacts in incisal third?
mesial of 8, 9
| all contacts of lower incisors
40
What aspects of incisors have contacts at junction?
Distal of 8, 9
| mesial of 7, 10
41
What is the only aspect of incisors that has contacts in middle third?
Distal of 7, 10
42
Where is the pulp cavity widest in maxillary central?
cervical level
43
Outline of pulp chamber of 8, 9 in young individuals?
triangle with base labially placed
44
Shape of pulp chamber of 8, 9 in old individuals
more round or crescent shaped due to secondary dentin deposition
45
Which one is bigger, young or old pulp chamber in 8, 9?
Young
46
Anterior tooth that has contacts in both anterior and posterior segments of opposite arch, at MIP.
Maxillary canine
47
MIP?
Maximum intercuspation
48
Does maxillary canine have contact on cusp tip?
no
49
Where does the maxillary canine fall in MIP?
The facial embrasure between the mandibular canine and first premolar
50
Contact points of 6, 11
Mesial - junction
| Distal - middle third
51
IS the 6 wider faciolingually or cervicoincisally?
faciolinguallly
52
Are mesial and distal halves of 6 symmetric?
Yes
53
Where is cusp tip of 11 placed relative to root axis line?
labial or at
54
What is the CEJ curvature of 6?
2.5mm mesial
55
Contour height of 11
facial / lingual - 0.5mm both in cervical third
56
How to differentiate between right and left upper canine
distal surface is fuller and more convex than the mesial surface
57
is the curvature of cervical line uniform in 6?
no - mesial is greater than distal
58
Is curvature of mesial surface same as distal in 11?
No mesial is straighter
59
Are cusp ridges uniform in 6?
No distal is longer
60
Are contact points in 10 at the same level?
No.
61
What is the difference between labiolingual and mesiodistal aspects of 6
It's thicker Labiolingually
62
Position of cusp tip relative to central long axis of 6
Labial and mesial to central long axis
63
Which contact of 11 is placed more cervical?
Distal
64
In what direction, if at all, will the apical third of the root curve in 11?
Distal
65
What lies mesial and distal to labial ridge?
Developmental depressions - shallow
66
Which labial ridges are more pronounced? 6, 11 or 22, 27?
6, 11
67
Which are the only cusped teeth that feature a functional lingual surface rather than occlusal surface?
Canines
68
Which surface of the canines is functional?
Lingual
69
Describe the shape of the distal portion of facial surface of 6
Middle third - convex
| Cervical third - concave
70
Is cervical line visible from incisal view in 11?
No because of convexity of crown
71
When do maxillary canines erupt?
Between 11, 12 years of age
72
After which teeth do 6 and 11 erupt?
Premolars
73
When do Mandibular canines erupt?
Between 9 and 10 years of age
74
Which canines erupt first?
Mandibular
75
Do premolars erupt before or after canines?
Before Maxillary canines, after mandibular canines
76
Teeth that erupt between 6 - 7 years of age
Mandibular centrals - 24, 25
| Maxillary and mandibular first molars
77
Teeth that erupt between 7-8 years of age
Maxillary centrals, Mandibular laterals
78
Teeth that erupt between 8-9 years of age
Maxillary laterals
79
Teeth that erupt between 9-10 years of age
Mandibular canines
80
Teeth that erupt between 10-11 years of age
Maxillary first premolars
81
Teeth that erupt between 10-12 years of age
Maxillary second premolars
| Mandibular first premolars
82
Teeth that erupt between 11-12 years of age
Maxillary canines
| Mandibular second premolars
83
Teeth that erupt between 11-13 years of age
Mandibular second molar
84
Teeth that erupt between 12-13 years of age
Maxillary second molar
85
Teeth that erupt around 17-21 years of age
All third molars
86
Which one has more pronounced cingulum, 6 or 27?
6
87
Which one is wider mesiodistally, 6 or 22?
6
88
Which one has a more straight mesial border (viewed facially), 11 or 22?
22
89
Which one has more incisally placed contacts, 11 or 27?
27
90
Cusp tip position of mandibular canine
Displaced lingually
91
Which cingulum is more pronounced - 6 or 27?
6
92
Which one has a distally displaced cingulum, 11 or 27
27
93
Longest cusp ridge on permanent canines
Distal
94
Most prominent labial ridge on permanent canines
Middle
95
Which third is the distal contact of 27 in?
Middle third
96
Which third is the mesial contact of 22 in?
Incisal third
97
From mesial aspect, which one is longer, 6 or 27?
27. Also narrower
98
In 27 is lingual surface bulbous?
No. flat.
99
How are marginal ridges on 22 and 27?
Parallel or slightly converging
100
Describe lingual pits and grooves in 27
None
101
Which one is more symmetrical 6 or 27? (Incisal aspect)
27
102
What is a peculiar characteristic of cusp ridges of mandibular canines?
Distal cusp ridge is rotated
103
CEJ curvature of 27
1 mm distal
104
Contour height of 22
< 0.5mm
105
Where is contour height of 27 located facially or lingually?
Both - cervical third
106
Which is the longest tooth in the mouth?
Maxillary canine
107
Which dimension of canines is greater - faciolingual or mesiodistal?
Faciolingual
108
Which permanent tooth has the longest crown?
Mandibular canine
109
Which surface of 27 is parallel with the long axis of the tooth?
Mesial (nearly)
110
Enumerate all nonsuccedaneous teeth
Permanent first, second and third molars
111
What are nonsuccedaneous teeth
Teeth that do not move into a position formerly occupied by a primary tooth
112
What primary teeth are visible at age 1 year?
Maxillary and mandibular incisors
113
Which teeth erupt at 6-10 months age?
Mandibular centrals
114
Which teeth erupt at 8-12 months of age?
Maxillary centrals
115
Which teeth erupt at 9-13 months of age?
Maxillary laterals
116
Which teeth erupt at 10-16 months of age?
Mandibular laterals
117
Which teeth erupt at 13-19 months of age?
Maxillary first molar
118
Which teeth erupt at 14-18 months of age?
Mandibular first molar
119
Which teeth erupt at 16-22 months of age?
Maxillary canines
120
Which teeth erupt at 17-23 months of age?
Mandibular canines
121
Which teeth erupt at 23-31 months of age?
Mandibular second molars
122
Which teeth erupt at 25-33 months of age?
Maxillary second molars
123
Which teeth shed at 6-7 years of age?
Maxillary and mandibular centrals
124
Which teeth shed at 7-8 years of age?
Maxillary and mandibular laterals
125
Which teeth shed at 9-11 years of age?
Maxillary and mandibular first molars
126
Which teeth shed at 9-12 years of age?
Mandibular canines
127
Which teeth shed at 10-12 years of age?
Maxillary canines
| Maxillary and mandibular second molars
128
By when is the calcification of roots normally completed?
Age of 3-4
129
At what stage of root formation does active eruption of teeth occur?
After two thirds of the root is formed.
130
List reducing sugars
```
Lactose
Maltose
Glucose
Galactose
Fructose
```
131
What kind of carbon do reducing sugars contain?
Free anomeric carbon
132
What is an anomeric carbon in reducing sugars?
Oxygen on C1 Atom is available for redox reaction
133
What is the anomeric carbon in reducing sugars called?
Carbonyl group
134
When is the carbonyl group on reducing sugars active?
When it is not attached to any other structure.
135
The carbonyl on which kind of sugars has reducing properties?
Monosaccharides.
136
When are the reducing properties of the carbonyl group lost?
When it forms a glycosidic bond
137
Reducing sugar test
Classically used to screen for diabetes due to excess free glucose in blood
138
What kinds of reactions are used to test for diabetes today?
Glucose oxidase linked reactions
139
Which sugar contains no free anomeric carbon?
Sucrose
140
Why does sucrose not contain free anomeric carbon?
Because the reducing groups of both glucose and fructose are involved in the glycosidic bond
141
How do monosaccharides combine into larger molecules?
They form glycosidic bonds
142
How do glycosidic bonds form?
Hydroxyl group of anomeric carbon of monosaccharide reacts with -OH or -NH group of another compound
143
What are te typical compounds that monosaccharides combine with to form glycosidic bonds?
- Alcohol
- Purine
- Pyrimidine
- Another sugar
144
Glucosuria
Presence of glucose in urine
145
Causes of glucosuria
Low insulin
High blood sugar
Impaired tubular reabsorption
High GFR
146
Threshold for glucosuria
160-180 mg/d
147
Glycosidic bond aka
Glycosidic linkage
148
What is a glycosidic bond
Two bond link between the rings in an oligosacharide or polysaccharide
149
Name a glycosaminoglycan functioning in synovial fluid
Hyaluronate
150
Glycoproteins
- Conjugated proteins
- Contain one or more saccharides lacking a serial repeating unit
- Covalently bound to a protein
151
What is the difference between proteoglycans and glycosaminoglycans?
Carbohydrate chains of proteoglycans are called glycosaminoglycans
152
How are GAG chains incorporated in proteoglycans?
GAG chains are linked covalently to a protein core
153
How many distinct classes of proteoglycans?
6
154
Name the 6 classes of proteoglycans
- Chondroitin sulphate
- Dermatan sulphate
- Keratan sulfate
- Heparan sulfate
- Heparin
- Hyaluronate
155
What % of carbohydrates do Proteoglycans contain?
95%
156
What kind of glycoproteins resemble carbohydrates more than they do proteins?
Proteoglycans
157
Which type of proteoglycan is different from the others and how?
Hyaluronate -
- Not sulfated
- Not covalently attached to protein
158
Features common to all GAGs
- long unbranched heteropolysaccharides
- Largely made up of disaccharide repeating units
- Contain hexosamine and a uronic acid
159
Common components of GAGs
Sulfate groups
160
How are sulfate groups linked to monosaccharides
Ester bonds
161
How are sulfate groups linked to Glucosamine
Amide bonds to the amino group of glucosamine
162
Why are GAGs highly charged
- Carboxyls of uronic acids
| - Sulfate groups
163
Function of GAGs in connective tissue
- Lubricants
| - Support elements
164
What components of GAGs are important in their roles in connective tissue
- Electrical charge
| - Macromolecular structure
165
What part of cellular structure do GAGs inhabit
Extracellular matrices and cell surfaces
166
On a cellular level what is the function of GAGs
They participate in
- Cell adhesion
- Signaling
167
Where will you find Hyaluronate
- Synovial fluid
- Vitreous humor
- ECM of loose connective tissue
168
What are the distinguishing characteristics of Hyaluronate?
- Large polymers
| - Shock absorbing
169
What kind of GAG do you find in cartilage?
Chondroitin sulfate
170
What are all the locations where you find Chondroitin sulfate?
Cartilage
Bone
Heart Valves
171
What is the most abundant GAG?
Chondroitin sulfate
172
What kind of GAG do you find in bone?
Chondroitin sulfate, keratan sulfate
173
What kind of GAG do you find in Skin?
Dermatan sulfate
174
What kind of GAG do you find in heart valves?
Chondroitin sulfate, dermatan sulfate
175
What kind of GAG do you find in vitreous humor?
Hyaluronate
176
What kind of GAG do you find in Basement membranes?
Heparan sulfate
177
What kind of GAG do you find in cornea?
Keratan sulfate
178
What kind of GAG do you find in cartilage aggregated with chondroitin sulfates?
Keratan sulfate
179
What is the most heterogenous GAG?
Keratan sulfate
180
What GAG serves as an anticoagulant?
Heparin
181
Which one is more sulfated -- heparin or heparan sulfate?
Heparin
182
Where do you find heparin?
It is a component of intracellular granules of mast cells lining the arteries of the lungs, liver and skin
183
What GAG is shock absorbing?
Hyaluronate
184
What kind of GAG do you find in ECM of loose connective tissue?
Hyaluronate
185
Which GAG is a component of cell surfaces?
Heparan sulfate
186
What does heparan sulfate contain more of than heparin?
Acetylated glucosamine
187
Where do you find heparin?
It is ta component of intracellular granules of mast cells lining the arteries of the lungs, liver and skin
188
What kind of GAG do you find in blood vessels?
Dermatan sulfate
189
What kind of bond is between glucose and fructose?
O-glycosidic bond
190
Where is the bond between glucose and fructose broken?
Intestine
191
What intestinal enzyme breaks down the bond between glucose and fructose?
Sucrase
192
What is the sugar formed due to the conjugation of glucose and fructose?
Sucrose
193
What kind of bond is present between two monosaccharides in a disaccharide?
Covalent
194
How many sugar units does a disaccharide contain?
Two
195
What is beer sugar?
Maltose
196
What kind of reaction joins the two components of maltose?
Condensation reaction
197
What happens in a condensation reaction?
A molecule of water is removed
198
What kind of bond is created between two molecules of glucose after a condensation reaction?
Glycosidic bond
199
What are the two components of maltose?
2 molecules of glucose
200
What is milk sugar?
Lactose
201
What is table sugar?
Sucrose
202
Components of Lactose
Glucose and galactose
203
Components of Sucrose
Glucose and fructose
204
What is the function of the intestinal enzyme invertase?
Conversion of sucrose into glucose and fructose
205
Where in the intestine are the enzymes that convert disaccharides into absorbable monosaccharides?
Small intestine
206
How are monosaccharides absorbed?
By enterocytes
207
What larger structures can monosaccharides link up to form?
- Disaccharides
- Oligosaccharides
- Polysaccharides
208
What kind of bond do disaccharides have?
O-glycosidic bond
209
What is an O-glycosidic bond?
When oxygen is involved in a glycosidic bond - -OH of anomeric carbon reacts with -OH of another compount
210
What is an N-glycosidic bond?
When nitrogen is involved - -OH of anomeric carbon bonds with -HN of another compound
211
What compounds contain O-glycosidic bonds?
Polysaccharides
212
What compounds contain N-glycosidic bonds?
- Glycoproteins
| - Nucleotides
213
What is the most important of the aldohexoses?
D-glucose
214
What kind of carbohydrates are glucose, fructose and galactose?
Monosaccharides
215
Types of monosaccharides
- Trioses
- Tetroses
- Pentoses
- Hexoses
216
What kind of monosaccharide is erythrose?
Tetrose
217
What kind of monosaccharide is glyceraldehyde?
Triose
218
What kind of compound is dihydroxyacetone?
Monosaccharide - triose
219
What kind of compound is ribose?
Monosaccharide - pentose
220
Types of monosaccharides based on most-oxidised functional groups
Aldoses and ketoses
221
What monosaccharides occur as cyclic rings in nature?
5, 6, 7, 8 carbon atoms
222
Examples of naturally occuring cyclic ringed carbohydrates
Ribose
Glucose
Fructose
Galactose
223
What is the naming of configurations of simple sugars based on?
The absolute configuration of glyceraldehyde
224
What is a chiral carbon
Asymmetric carbon
225
The names of which compounds are determined by absolute configuration of glyceraldehyde?
- Monosaccharides
| - Amino acids
226
What is the difference between the D form and the L form?
In a Fisher projection, D form has hydroxyl group on right, L form has hydroxyl group on left.
227
Which form of sugars are the most common in nature?
D form - related to D-glyceraldehyde
228
What is xylose?
A monosaccharide
229
What is mannose?
A monosaccharide
230
What does glucan transferase hydrolyse?
Glycogen
231
What is the solubility of polysaccharides?
They are insoluble because they have large molecules
232
Main functions of polysaccharides in living organisms
- Storage molecules
| - Structural materials
233
What are the structural polysaccharides?
Cellulose
234
What polysaccharides act as storage molecules?
- Starch
| - Glycogen
235
Polysaccharides that contain a single monosaccharide species
Homopolysaccharides
236
List of homopolysaccharides
- Starch
- Glycogen
- Dextrans
- Glucans
237
What kind of molecules are contained in starch?
alpha glucose molecules
238
What kind of reactions bind molecules in starch?
Condensation reactions
239
Main components of starch
Amylose
| Amylopectin
240
What kinds of chains do amylopectin molecules form in starch?
Highly branched chains with alpha-1,6 linkages
241
What enzyme acts on starch?
Alpha amylase
242
What kind of chemical reaction does alpha amylase have with starch?
It rapidly hydrolyses starch
243
Where is alpha amylase secreted from?
- Parotid
| - Pancreas
244
What component of starch is unbranched?
Amylose
245
What compound creates straight chains in starch?
Amylose
246
How many glucose residues does glycogen contain?
10,000 to 40,000.
247
How are glucose residues held together in glycogen?
a-1,4 glycosidic bonds
248
How does branching occur in Glycogen?
1 in 12 glucose residues serves as a branch point
249
What kinds of bonds do branch points have within glycogen?
a-1,6 glycosidic bond
250
What part of the body is glycogen especially abundant in?
Liver
251
How are glucose units removed from glycogen?
Glycogen phosphorylase
252
How is glycogen cleaved beyond a branching point?
2 enzymes:
Glucantransferase
amylo-alpha-1,6-glucosidase
253
What is the most common organic compound on earth?
Cellulose
254
What is "dietary fiber"?
Cellulose
255
What is "roughage"?
Cellulose
256
Which carbohydrate acts as a hydrophilic bulking agent for feces?
Cellulose
257
What linkages are part of cellulose?
B1-4 linkages
258
What are the monosaccharides that makes up cellulose?
Glucose
259
What does the term glycan refer to?
- Polysaccharide or
| - Oligosaccharide
260
What is the ground surface of extracellular matrix made up of?
Proteoglycans
261
How are GAGs attached to the protein in proteoglycans?
In a brush-like fashion
262
Functions of Proteoglycans
- lubricants
- extracellular matrix
- Being a molecular sieve
263
What kind of proteins are glycoproteins?
Conjugated proteins
264
How is the carb portion of most glycoproteins different from proteoglycans?
it is shorter and branched.
265
What is special about the glyco- part of glycoproteins
They lack a serial repeating unit
266
What kinds of molecules do glycoproteins serve as?
- Hormones
- Enzymes
- Antibodies
- Structural proteins
267
What are glycolipids aka?
Sphingolipids
268
Where are glycolipids found?
In cell membrane
269
What part of the glycolipid extends into the extracellular space?
Carbohydrate portion
270
What are glycolipids derived from?
Ceramide - a lipid
271
Types of glycolipids
- Cerebrosides
- Globosides
- Gangliosides
272
Which ones are long and straight - Proteoglycans or Glycoproteins?
Proteoglycans
273
Role of glycolipids
Cell membrane receptors
274
How does chondroitin sulfate provide structure?
It holds water and nutrients, allows other molecules to move through cartilage
275
Roles of chondroitin sulfate
- Building block for proteoglycan molecules
| - Anti-inflammatory
276
Why is the function of chondroitin sulfate of holding water and nutrients important?
Cartilage doesn't have a blood supply
277
How does chondroitin sulfate help in joints?
It contributes to
- Strength
- Flexibility
- Shock absorption
278
Ground substance aka
Extracellular matrix
279
Functions of ground substance
- Holds the cells of a tissue together
| - Provides a porous pathway for diffusion of nutrients and oxygen to individual cells
280
How does ground substance help get nutrients and oxygen to individual cells?
By providing a porous pathway
281
What is ground substance composed of?
- heteropolysaccharides (GAGs)
- (linked to) protein
- (to form) proteoglycans
- fibrous proteins
282
Name an enzyme that liquefies the ground substance
Hyaluronidase
283
Actions of hyaluronidase
- Splits hyaluronic acid
- lowers the viscosity of ground substance
- Increases the permeability of connective tissue
- Increases the absorption of fluids
284
Which is the only GAG that is not attached to a protein?
Hyaluronate
285
How are dextrans produced?
Extracellularly by bacteria and yeast
286
What is the constituent monosaccharide in dextrans?
Glucose
287
What is the enzyme used to produce dextrans?
Glucosyl transferase
288
What is glucosyl transferase aka
Dextran sucrase
289
What is the substrate from which Dextrans are created?
Sucrose
290
Are there any side products from dextran production?
Yes - fructose
291
How is fructose formed from the dextrification of sucrose?
Fructose is formed into levans (fructans)
292
How is fructose created as a byproduct of dextran production stored?
It is stored intracellularly as reserve nutrients.
293
What is the most notable bacteria that produces dextran from sucrose?
Strep mutans
294
Name a sticky polymer of glucose
Dextran
295
What kinds of linkages do glucose molecules have within dextran?
a-(1,6) linkages with some a-(1,3) branches
296
How are dextrans created from sucrose?
Glucosyl transferase splits sucrose into glucose and fructose and links the glucose molecules into a dextran polymer
297
How is the dextran stored after creation?
IT is deposited as a thick glycocalyx around the cell
298
How are dextrans related to dentistry?
They seem to be essential for the cariogenecity of Strep mutans.
299
How does adhesion of bacteria to tooth surface increase on creation of dextrans?
Fructans (levans) - the byproducts of dextran production - increase adhesion of bacteria to tooth surfaces and promote formation of dental plaque
300
How are fructans formed?
From the fructose moiety of sucrose by the enzyme fructosyl transferase
301
Fructosyl transferase aka
levan sucrase
302
Essentially, what are fructans?
Reserve nutrients for bacteria
303
Which one is more abundant - cones or rods?
Rods
304
What pigment do rods contain?
Rhodopsin
305
What kind of pigment is rhodopsin?
Photopigment
306
Are rods responsible for color vision or cones?
Cones
307
What are rods used for?
Dark adaptation
308
Where are rods and cones located?
Retina
309
What is the innermost layer of the eye?
Retina
310
What are the visual receptors of the retina?
Rods and cones
311
How many types of photopigments are there?
4
312
What are the different types of photopigments?
Rhodopsin (rods)
Photopsin I, II, III
Melanopsin
313
What are the major components of a photopigment?
Opsin - a protein
| Retinal - a chromophore molecule
314
Function of opsins
They confer specific light-sensitive properties on each photopigment
315
Are opsins uniform throughout?
They differ from pigment to pigment
316
What is Retinal produced from?
Vitamin A
317
How is rhodopsin synthesised?
Retinal is added to an opsin to synthesize rhodopsin
318
What characterises the entire rod system?
A relative lack of colour discrimination
319
How are rods distributed in the retina?
They are numerous in the periphery of the retina
320
What are the different types of cones?
3 - Red green and blue
321
How are cones distributed in the retina;?
They are concentrated in the centre of the retina, esp in the fovea.
322
How do rods work?
During dark adaptation, rhodopsin is synthesised in the rods
323
What causes night blindness?
Severe Vitamin A deficiency over many months
324
When are cones principal photoreceptors?
- Daylight
| - Brightly lit areas
325
Are rods more abundant or cones?
Rods
326
Which ones are more sensitive, cones or rods?
Rods
327
Which have greater acuity, rods or cones?
Cones
328
What is the cornea?
The crystal clear dome that covers the front of the eye
329
What part of the eye is responsible for the majority of the bending of light rays?
Cornea, NOT lens
330
Which part of the eye does the majority of the focusing, cornea or lens?
Cornea
331
Does the shape of the cornea change?
No. (Age related changes aside)
332
What is the role of the lens in focusing the light?
It finishes the focusing of the light
333
Of the cornea and lens which one can change shape
Lens
334
How does the eye focus on near objects?
Lens fine tunes vision by changing shape to focus on near objects
335
What part of the eye is affected in cataract?
lens
336
What part of the retina receives the focus of the object of regard?
Fovea
337
What kinds of cells are packed in the area of the fovea?
Cones
338
Which one is watery - aqueous humour or vitreous humour?
Aqueous
339
Where is vitreous humour found?
Posterior segment of the eye
340
What is vitreous humour?
Thick, gelatinous material
341
What do you call the point where the cornea ends and the iris begins?
Iridocorneal angle
342
Where is the Canal of Schlemm located?
Next to the iridocorneal angle
343
What separates the chambers of the anterior segment of eye?
Iris
344
Zonule aka
Suspensory ligaments
345
What does the zonule connect
Ciliary body and lens
346
What part of the ear does a sound wave strike first?
Tympanic membrane
347
How many types of labyrinths does the cochlea have?
2 - bony and membranous
348
Where is endolymph found?
Membranous labyrinth of cochlea
349
What do you find in the bony labyrinth of the cochlea?
Perilymph
350
What is the last part of the ear to be stimulated before transmission of nerve impulses along the cranial nerve?
Hair cells on the organ of Corti
351
What membrane stimulates the cochlear parts to move?
Membrane of the oval window
352
Major divisions of the ear
External
Middle
Inner
353
What part of the ear is the vestibule located in?
Inner ear
354
what are the parts of the vestibule?
Saccule and utricle
355
Parts of the external ear
- Auricle
| - External auditory canal
356
Auricle aka
Pinna
357
What part of the ear directs sound waves?
Pinna
358
Cerumen aka
Brown earwax
359
What part of the ear serves as a resonator?
External auditory meatus
360
What does the external auditory meatus contain?
Hair
| Cerumen
361
Contents of the middle ear
- Auditory Tube
| - Ossicles
362
Middle ear aka
Tympanic cavity
363
Which bone is the middle ear located in?
Temporal
364
What fills the middle ear?
Air
365
Name the ossicles
Malleus
Incus
Stapes
366
How much do the ossicles amplify sound?
22-fold
367
How does sound travel from the tympanic membrane to the oval window?
Ossicles
368
Contents of the inner ear
- Vestibule
- Semicircular canals
- Cochlea
369
What is the inner ear formed of?
A membranous labyrinth within a bony labyrinth
370
What is the major function of the vestibule?
It is associated with a sense of balance
371
What part of the ears is concerned with equilibrium?
Semicircular canals
372
What are the membranes contained within the cochlea?
- Vestibular
| - Basilar
373
What part of the inner ear is responsible for hearing?
Cochlea
374
What is the shape of the organ of Corti?
Spiral
375
What are the receptors for hearing and where are they present?
Hair cells, located within the organ of Corti
376
What is the basic functional unit of hearing?
Cochlea
377
What is the function of cochlea?
Transforms fluid vibrations from sound waves into a nerve impulse
378
What part of the ear is the tympanic membrane in?
Middle ear
379
What part of the ear is the eustachian tube in contact with?
Tympanic cavity in the middle ear
380
What is used to induce mydriasis?
Tropicamide
381
What does tropicamide do?
Induces mydriasis
382
The pupil is abnormally dilated in miosis or mydriasis?
Mydriasis
383
Causes of miosis
- Normal reaction to an increase in light
- Some drugs
- Pathological conditions
384
Causes of mydriasis
- Drug induced
| - Disease
385
Nearsightedness aka
Myopia
386
Where are faraway objects focused wrt the retina in myopic patients?
In front of the retina
387
Causes of Myopia
- Steeper than normal cornea
| - Longer than normal eye
388
What kind of lenses are used to treat myopia?
Concave
389
Where does light focus in hyperopia?
Behind the retina
390
Farsightedness aka
Hyperopia
391
Causes of hyperopia
- Flatter cornea
| - Shorter eye
392
What kinds of lenses are used to treat hyperopia?
Convex
393
Causes of astigmatism
Non-uniform curvature of the lens
394
Treatment of astigmatism
Cylindric lenses
395
Causes of presbyopia
Loss of elasticity of lens with age
396
Treatment of presbyopia
Bifocals
397
Normal range for Hb in women
12-16 g/dL
398
Normal range for Hb in men
13-18 g/dL
399
Structure of Hb
Quaternary protein consisting of four tertiary polypeptide chains
400
What kind of polypeptide chains does Hb have?
2 alpha
| 2 beta
401
What are the iron-containing heme groups associated with in Hb?
Polypeptide chains (4)
402
How many Hb molecules does a single erythrocyte contain?
Up to 300 million
403
How many iron atoms does one Hb molecule contain?
4
404
How many Oxygen molecules can one Hb molecule bind to?
One
405
What is the maximum oxygen carrying capacity of one Hb molecule?
8 atoms of oxygen
406
How many mL is one dL?
100 mL = 1 dL
407
Normal blood values of Hb in a newborn
14 - 20 g/dL
408
What does Hb value depend on?
- Number of RBCs
| - Amount of Hb in each RBC
409
Conditions with low Hb value
- Anemia
- Hyperthyroidism
- Cirrhosis of liver
410
Conditions with high Hb value
- Polycythemia
- COPD
- Congestive Heart Failure
411
Bohr effect
Very strong in the fetus - acid in the tissues assists in oxygen unloading from Hb, to promote oxygen delivery to the tissues
412
Hb in which blood is more saturated? Leaving the lungs or returning?
Leaving - 98%
| Returning - 75%
413
What is the difference in mechanisms of transport of oxygen and carbon dioxide in blood?
97% of O2 is transported with Hb
Only 30% of CO2 is transported as carbaminohaemoglobin
414
What are the mechanisms of transportation of CO2 in blood?
Bicarbonate
Carbon Dioxide
Carbaminohaemoglobin
415
What % of total plasma protein is Albumin?
60%
416
What % of the colloid osmotic pressure of the plasma does albumin contribute to?
80%
417
What is colloid osmotic pressure vital for?
Preventing edema
418
How many amino acids are contained within Albumin?
585
419
How many carbohydrates are present within Albumin?
none
420
What is the effect of albumin on plasma viscosity?
It does not increase it to the same extent as more elongated proteins of the same molecular weight
421
What is the molecular weight of albumin?
66,000 D
422
What is the isoelectric point of albumin?
Acidic
423
How does the kidney treat albumin?
Because of its isoelectric point and its molecular weight, it is not excreted by the kidneys
424
Is albumin present in interstitial fluid and lymph?
Yes, in lower concentrations than in plasma
425
What is the difference in amounts of plasma between interstitial fluid and plasma?
Total amount in interstitial spaces slightly exceeds that in vascular compartment
426
How is albumin returned to the blood from the interstitial spaces?
Lymph
427
Which one is more, interstitial fluid volume or plasma volume?
Interstitial fluid (12% of body volume)
Plasma is 4.5% of body volume.
428
Why does albumin contribute so much to colloid osmotic pressure of the plasma?
Because it is one of the most hydrophilic plasma proteins
429
What does colloid osmotic pressure depend on?
The amount of water and electrolytes that a protein attracts to its surface
430
What is the importance of colloid osmotic pressure?
It is necessary to prevent edema
431
What is the force that is opposite to the colloid osmotic pressure?
Hydrostatic pressure
432
Which of the two forces - hydrostatic pressure and colloid osmotic pressure - pushes fluid from the blood into the interstitial space?
Hydrostatic pressure
433
How is the fluid balance across the endothelium maintained?
As long as hydrostatic pressure and colloid osmotic pressure cancel each other out
434
At what albumin concentration does edema occur?
When it drops below 2 g/dL
435
Other causes for edema
- Increase in capillary permeability
- Venous obstruction
- Impaired lymph flow
- Congestive heart failure with an increased venous pressure
436
Which organ in the body is chiefly responsible for regulation of osmotic pressure in the body?
Kidney. It regulates the reabsorption of water in response to ADH
437
WHat does albumin have binding sites for?
- Fatty acids
- Thyroxine
- Cortisol
- Heme
- Bilirubin
- Many other metabolites
438
What are the majority of plasma proteins?
Glycoproteins (not albumin)
439
What is the principal hormone for serum calcium regulation?
Parathormone
440
How much Calcium ions does the human body contain?
1-1.5 k
441
Where is most of the calcium of the body contained?
98% of the calcium of the body is contained in the mineral substance of the bone
442
What are other substances that control calcium levels?
- Vitamin D
| - Calcitonin
443
What substances increase serum calcium levels?
PTH
| Vitamin D
444
What does calcitonin do to blood calcium levels?
It tones down blood calcium
445
Are people with Parathyroidism more or less susceptible to fractures?
More, because PTH primarily increases concentration of serum calcium
446
What happens to renal calcium excretion in hyperparathyroidism?
Decreased (in order to increase blood calcium levels)
447
What effect does PTH have in elderly people?
Bone resorption with low dietary calcium is intensified
448
When do you observe increased calcium blood levels?
- Hypervitaminosis D
- Hyperparathyroidism
- Bone cancer
- Other bone diseases
449
When do you observe decreased calcium blood levels?
- Severe diarrhea
- Hypoparathyroidism
- Avitaminosis D
450
What are the disorders precipitated due to Avitaminosis D?
- Rickets
| - Osteomalacia
451
What hormones work together to keep a balance within serum calcium levels?
PTH and Calcitonin
452
What hormone is complementary to Calcitonin?
PTH
453
How does calcitonin counteract actions of PTH?
When PTH increases serum calcium, calcitonin tones down this level by
- depositing more in bone
- increasing the excretion
454
What is normal plasma phosphorous concentration?
4 mg%
455
What regulates plasma phosphorous concentration?
Parathyroid hormone
456
How does PTH regulate plasma phosphorous concentration?
Increased hormone causes the kidneys to increase the rate of phosphate excretion, which decreases the plasma phosphate concentration
457
What hormones increase bone resorption?
PTH
| Vitamin D
458
What does Calcitonin do to bone?
It decreases bone resorption
459
Which Ca regulatory hormone has no role to play in kidneys or intestines?
Calcitonin
460
Which hormone is secreted when serum Calcium is low?
PTH
461
Does serum levels of phosphate have an effect on PTH levels?
No
462
What % of body weight is blood?
8%
463
What is hematocrit
Proportion of cellular elements of blood
464
What is the most important transport medium in the body?
Blood
465
Serum = blood minus ?
Fibrin clot and blood cells
466
Physical nature of serum
Clear, thin and sticky fluid
467
How does serum differ from plasma?
Serum lacks fibrin and other coagulation products
468
Plasma = blood minus ?
Formed elements
469
What % of blood is plasma?
55%
470
What are the contents of plasma?
Proteins
Water
Other solutes
471
What % of plasma is proteins?
7%
472
What proteins are contained within plasma?
Albumins
Globulins
Fibrinogen
473
What % of plasma is water?
91%
474
What is the major content of plasma?
Water
475
What are the trace elements of plasma (other solutes)?
```
Metabolic end products
Food materials
Respiratory gases
Hormones
Ions
```
476
What % of blood is hematocrit?
45%
477
What are the formed elements?
Erythrocytes
Leukocytes
Thrombocytes
478
Function of platelets
Hemostasis - agglutinate and plug small ruptured vessels
479
How many steps are in the process of hemostasis?
Three
- Vasoconstriction
- Platelet aggregation
- Coagulation
480
What is the need for an extrinsic or intrinsic pathway?
These pathways form prothrombin activator, which helps in production of thrombin from prothrombin
