Official NBDE Part 1 Study Q & A Thread

[tinman831]

Please post all study questions/answers for the NBDE Part 1 in this thread. Good luck!

As a side note, this is not the place for sales ads. Discussion of remembered questions appearing on the exam is also not permitted.

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[GOLF82]

As far as i kw Osteoclasts do not have PTH receptors.. its the osteoblasts which activate them.. butmby none of the above Does anyone else have an answer??

For IL-1

Try Wikipedia http://en.wikipedia.org/wiki/IL1A
See the biological activity

 

[jalika]

Pure rotation of the mandible involves which two planes of movement?
Frontal
Horizontal
Saggital

The correct answer per Decks is Frontal and Sagittal.

Can somebody explain the answer including why horizontal is not right?
Thanks

i am confused by this also. can someone explain?

 

[jalika]

can someone explain this question?
maxillary molars of the 2 dentitions can be differentiated from mand molars by
a. number of cusps
b. number of dev brooves
c. occlusal outlines
d. arrangement of roots
e. numbere of roots
f. size of crowns

1. a,b,c and d
2. a,b,c,e
3. a,d,e,f
4. c,d,e,f
5. c,d,e
6. d,e,f

 

[sweetsmile1]

1 - Assuming that P50=26 torrs, underconditions
where p02 =30 torrs, the average number of
o2 molecules bound per hemoglobin would be?
a) less than 1
b) almost 2
c) more than 2
d) more than 3

ans is c) more than 2

plz tell me how to solve this. plz


2 - For a reaction catalyzed by an enzyme with a
Km= 1 mM, which of the following represents
the effect on the velocity if is changed from
10 mMto 20 mM? (Assume that the enzyme
obeys Michaelis-Menten kinetics.)
a)small decrease
b)small increase
c)remains same
d)two fold increase
e)twenty fold increase

answer is b) small increase

somebody plz explain.

 

[GOLF82]

1 L.. question number 334; hw is the answer B, my answer was E; what is it that i am missing here??

I beleive you are talking about the question about the amoxicillin allergic person. . Actually, there is no E choice; there is D which was my answer too, but the answer sheet says it is B.

I tried to find any relation between IgE and cytotoxic cell with penicillin (
Amoxicillin), but I couldn't.

I hope I am talking about the same question.

Anyone, any idea. Any thought would help.

 

[GOLF82]

i am confused by this also. can someone explain?

Think about the horizontal plane is the movement to the right and left ( or in clear talking going purely to the left or to the right). There is no left or right ( lateral) movements to the left or to right in pure rotational movement of the TMJ. Therefore, the planes in which the mandibule moves in pure rotation are frontal and sagital.

By the way, there is a discussion and some good explanation about this question and the subject in the first or second page of this forum.

 

[GOLF82]

1 - Assuming that P50=26 torrs, underconditions
where p02 =30 torrs, the average number of
o2 molecules bound per hemoglobin would be?
a) less than 1
b) almost 2
c) more than 2
d) more than 3

ans is c) more than 2

plz tell me how to solve this. plz


2 - For a reaction catalyzed by an enzyme with a
Km= 1 mM, which of the following represents
the effect on the velocity if is changed from
10 mMto 20 mM? (Assume that the enzyme
obeys Michaelis-Menten kinetics.)
a)small decrease
b)small increase
c)remains same
d)two fold increase
e)twenty fold increase

answer is b) small increase

somebody plz explain.

The P50 means the pressure when half of the Hb is saturated by the oxygen. Max. capacity of the Hb to bind to O2 is 4 molecules( when it is fully saturated). Therefore, Hb with half saturation has 2 O2 mol. You can imagine if 2 molecules of Hb would be filled in pressure 27. How many molecules would be filled in pressure more than 27(p50) ???


Km is the conc. of substrate that produce half max. velocity. If you put Km conce. you would produce 1/2 velocity. Increase the conce., will increase the velocity until you reach the max. velocity, but ccording to Michaelis-Menten the increase of the sub. conce. beyond the max. velocity have none or small
effect on the velocity.
Imagine if your Km is one, you expected the max. velocity would be met at 3 or 4 or even 5 or 6 then after that there will be small or nill increase in the velocity(which is the answer)

I hope this would help you.

 

[Anaita]

The P50 means the pressure when half of the Hb is saturated by the oxygen. Max. capacity of the Hb to bind to O2 is 4 molecules( when it is fully saturated). Therefore, Hb with half saturation has 2 O2 mol. You can imagine if 2 molecules of Hb would be filled in pressure 27. How many molecules would be filled in pressure more than 27(p50) ???


Km is the conc. of substrate that produce half max. velocity. If you put Km conce. you would produce 1/2 velocity. Increase the conce., will increase the velocity until you reach the max. velocity, but ccording to Michaelis-Menten the increase of the sub. conce. beyond the max. velocity have none or small
effect on the velocity.
Imagine if your Km is one, you expected the max. velocity would be met at 3 or 4 or even 5 or 6 then after that there will be small or nill increase in the velocity(which is the answer)

I hope this would help you.

bang on!!

 

[PooKan]

In normal occlusion whn mandible makes RIGHT working movement , wht s in relation with the ML cusp of the maxillary LEFT 1st Molar?

Doubt :- in laterotrusive WORKING side movement , mandible moves LATERALLY n DISTALLY (not sure, correct me if iam wrong)...wht happens to NON-WORKING side? how does it move

 

[Anaita]

In normal occlusion whn mandible makes RIGHT working movement , wht s in relation with the ML cusp of the maxillary LEFT 1st Molar? Could you plz post the question with choices

Doubt :- in laterotrusive WORKING side movement , mandible moves LATERALLY n DISTALLY (not sure, correct me if iam wrong)...wht happens to NON-WORKING side? how does it move

Working side condyle moves laterally about the vertical axis, non working side condyle moves forward, downward and medially.. under normal circumstances contacts on balancing side are deleterious.. contacts on working side.. canine protected and mutually protected or group function..

The term ‘Mutually protected occlusion’ means that one or a group of teeth mutually protect the remaining ones from constant biting forces. Simply put that when a person bites on his/her front teeth the posterior teeth DO NOT contact, hence relieving them of occlusal loading. (remmember Christensen’s Phenomena. This happens when one bites on the front anterior teeth.
When there is a lateral component added to the way a person bites which is normal (Anterolateral) then probably only the Canine on the working side maybe the tooth in contact dis-occluding all the other teeth. This is called ‘Canine Guided Occlusion’( The Canines Guide the Occlusion) Also called ‘Cuspid Rise’. A Type of Mutually Protected Occlusion.
In the same situation when a group of teeth on the working side Eg: the Canine, Ist Premolar, and the 2nd Premolar are in contact and the other teeth are Dis-occluded then this type of Mutually Protected Occlusion is Termed ‘GROUP FUNCTION’ simply because a group of teeth function to bring about a mutually protected Occlusal Scheme.
Hope this helps!!

 

[Anaita]

I beleive you are talking about the question about the amoxicillin allergic person. . Actually, there is no E choice; there is D which was my answer too, but the answer sheet says it is B.

I tried to find any relation between IgE and cytotoxic cell with penicillin (
Amoxicillin), but I couldn't.

I hope I am talking about the same question.

Anyone, any idea. Any thought would help.

Know that Penicillin is a hapten, so has to bind to a carrier tissue for it to take efeect.. does that probably explain why the answer.. confused Evryone else seems to have understood it

 

[PooKan]

Working side condyle moves laterally about the vertical axis, non working side condyle moves forward, downward and medially.. under normal circumstances contacts on balancing side are deleterious.. contacts on working side.. canine protected and mutually protected or group function..

The term ‘Mutually protected occlusion’ means that one or a group of teeth mutually protect the remaining ones from constant biting forces. Simply put that when a person bites on his/her front teeth the posterior teeth DO NOT contact, hence relieving them of occlusal loading. (remmember Christensen’s Phenomena. This happens when one bites on the front anterior teeth.
When there is a lateral component added to the way a person bites which is normal (Anterolateral) then probably only the Canine on the working side maybe the tooth in contact dis-occluding all the other teeth. This is called ‘Canine Guided Occlusion’( The Canines Guide the Occlusion) Also called ‘Cuspid Rise’. A Type of Mutually Protected Occlusion.
In the same situation when a group of teeth on the working side Eg: the Canine, Ist Premolar, and the 2nd Premolar are in contact and the other teeth are Dis-occluded then this type of Mutually Protected Occlusion is Termed ‘GROUP FUNCTION’ simply because a group of teeth function to bring about a mutually protected Occlusal Scheme.
Hope this helps!!

thankz Anaita
answer :- sulcus btw distofacial and distal cusps of mandibular 1st molar..
how did they come to this anwser...
and the explanation u gave is right but how and whn do u apply it
and how do u solve lateral and laterotrusive , working and non- working side type of questions?

 

[PooKan]

The condyle on the non-working side generally rotates about a:
A. Sagittal axis only
B. Horizontal axis only
C. Horizontal axis & translates laterally
D. Vertical

 

[sweetsmile1]

Thank you so much for the explanation It will definitely be of great help in the exam...

The P50 means the pressure when half of the Hb is saturated by the oxygen. Max. capacity of the Hb to bind to O2 is 4 molecules( when it is fully saturated). Therefore, Hb with half saturation has 2 O2 mol. You can imagine if 2 molecules of Hb would be filled in pressure 27. How many molecules would be filled in pressure more than 27(p50) ???


Km is the conc. of substrate that produce half max. velocity. If you put Km conce. you would produce 1/2 velocity. Increase the conce., will increase the velocity until you reach the max. velocity, but ccording to Michaelis-Menten the increase of the sub. conce. beyond the max. velocity have none or small
effect on the velocity.
Imagine if your Km is one, you expected the max. velocity would be met at 3 or 4 or even 5 or 6 then after that there will be small or nill increase in the velocity(which is the answer)

I hope this would help you.

 

[buntydr83]

I beleive you are talking about the question about the amoxicillin allergic person. . Actually, there is no E choice; there is D which was my answer too, but the answer sheet says it is B.

I tried to find any relation between IgE and cytotoxic cell with penicillin (
Amoxicillin), but I couldn't.

I hope I am talking about the same question.

Anyone, any idea. Any thought would help.

some answers are wrong so don't worry......

the ans should be penicillin binds with Ig E on mast cell....

 

[Anaita]

some answers are wrong so don't worry......

the ans should be penicillin binds with Ig E on mast cell....

Thanx.. wasted too much time over this one..

 

[Anaita]

The condyle on the non-working side generally rotates about a:
A. Sagittal axis only
B. Horizontal axis only
C. Horizontal axis & translates laterally
D. Vertical

Are you sure the q is on nonworking side..
coz the working side condyle moves about the vertical axis as it translates laterally

 

[Hatico]

17. Cytokines causing bone resorption
a. IFN-alpha & beta
b. IL1-alpha & beta

IFN gamma stimulates macrophages ( osteoclasts )
alfa and beta stimulate fibroblasts ( osteoblasts )

IL-1 interfers with osteoclasts function but does not stimulate them.

 

[sweetsmile1]

Q - Which of the following disorders is LEAST likely to
be included in the differential diagnosis of a
patient with acute appendicitis?
A. Crohn's disease
B. Duodenal peptic ulcer
C. Meckel's diverticulitis
D. Pelvic inflammatory disease
E. Gastroenteritis with mesenteric adenitis

ASDA ans is B.

I thought the ans is A coz crohn's disease is a chronic condition and the rest all are acute conditions. Is my thought right?If not then any explaination for the ans B?

 

[Hopeless101]

Which of the following disorders is LEAST likely to
be included in the differential diagnosis of a
patient with acute appendicitis?
A. Crohn's disease
B. Duodenal peptic ulcer
C. Meckel's diverticulitis
D. Pelvic inflammatory disease
E. Gastroenteritis with mesenteric adenitis

The answer is B and NOT A because Crohns disease dominant manifestation is abdominal pain.The pain is so abrupt that abdominal exploration is performed with diagnosis of appendicits (Page 574 Robbins)..The rest of the answers may presents many of the clinical features of aqppendictis (these are mesentric lymphadenitis, mesentric adenitis, pelvic inflamatory disese, rupture of ovarian follicles, ectopic pregnancy, meckel diverticulus)....Hope these helps...may exam is in three weeks and scared to death....

 

[PooKan]

Are you sure the q is on nonworking side..
coz the working side condyle moves about the vertical axis as it translates laterally

yes my freind has asked me this question..and the answer s saggital ...
but she might be wrong.... but can u explain me this concept please?

 

[Crick]

Do Enamelins stay behind as interrod structure and are most abundant? I thought Amelogenin was most abundant?

someone can explain?

thank.

 

[buntydr83]

Do Enamelins stay behind as interrod structure and are most abundant? I thought Amelogenin was most abundant?

someone can explain?

thank.

enamel has 96% inorganic , 1% organic, 3% water......
most of organic compound is formed by amelogenin which is prolin rich protein, it's role is unclear but some believes that it has omething to do with arrengement of enamel rods..........small portion contain enamelin

 

[GOLF82]

some answers are wrong so don't worry......

the ans should be penicillin binds with Ig E on mast cell....

I think this the only explanation.

Thank you very much

 

[GOLF82]

Thank you so much for the explanation It will definitely be of great help in the exam...

Welcome and good luck

 

[Hatico]

What is the most powerful muscle for Vomiting???

rectus abdominis?

 

[drgreen]

In the dental decks (card 16) it says that the hematocrit is the proportion of cellular elements in the total blood volume (namely RBC, WBC and Platelets), but I had always thought that Hct was just RBCs.

 

[liriano]

Q - Which of the following disorders is LEAST likely to
be included in the differential diagnosis of a
patient with acute appendicitis?
A. Crohn's disease
B. Duodenal peptic ulcer
C. Meckel's diverticulitis
D. Pelvic inflammatory disease
E. Gastroenteritis with mesenteric adenitis

ASDA ans is B.

I thought the ans is A coz crohn's disease is a chronic condition and the rest all are acute conditions. Is my thought right?If not then any explaination for the ans B?

All of the other answers are colon-located or lower. Meckel's is often mistaken for appendicitis. Duodeneal peptic ulcer would result in heartburn-like pain, not radiating towards the umbilicus like the others. Correct me if I'm wrong.

 

[dentdoc10]

In the dental decks (card 16) it says that the hematocrit is the proportion of cellular elements in the total blood volume (namely RBC, WBC and Platelets), but I had always thought that Hct was just RBCs.

Total blood volume/complete blood count = RBC+WBC+Platelets+Hb i.e cellular elements + Hemoglobin
When blood is centrifuged, the formed elements and plasma separate out with formed elements at the bottom and plasma on top. The part/ portion of the separated formed elements is the total blood volume

Hematocrit is the proportion/ fraction / the % of the total blood volume occupied by RBC
It refers only to RBC

 

[drgreen]

Decks Biochem Card 62 says that the van der Waals interactions between stacked bases in DNA are the strongest non covalent forces in the double helix. Aren't H bonds stronger???

 

[DancingKoala]

Hi guys,

I came across a question that asks which ones exert the effect on calcium metabolism and the answers were
androgen, estrogen, thyroid hormone, and parathyroid hormone.


I am aware of thyroid and parathyroid hormone increasing and decreasing blood calcium level.

However, I don't understand how anderogen and estrogen can affect and how it affect the calcium metabolism.

Thank you in advance.

 

[Hatico]

However, I don't understand how anderogen and estrogen can affect and how it affect the calcium metabolism.

Thank you in advance.

Estrogen affects calcium absorption and vitamin D Metabolism ( basis for postmenopausal osteoporosis)
Androgens increase intracellular calcium ( basis for prostate cancer )

 

[DancingKoala]

I have one more question

which of the following teeth might possess 3 cusps?
1) max 2nd premolar and max 1st molar
2) max 2nd premolar and mand 1st premolar
3) max 1st molar and mand 2nd molar
4) max 2nd molar and mand 1st premolar
5) max 2nd molar and mand 2nd premolar

I think the way to solve this problem is to find teeth that has either +1 or -1 from 3 cusps since 1cusp or 5cusp will have less chance of having 3 cusps.
The correct answer is 5) max 2nd molar and mand 2nd premolar.

I think max 2nd molar has 4 cusps and mand 2nd premolar has 2 cusps.
But, how about 4) max 2nd molar and mand 1st premolar?
I thought all anterioer teeth have 1 cusp, all premolars have 2 cusps, max 1st molar has 5 cusps (or is 4 normal and cusp of carabelli abnormal?).

I am confused. Please help me~

 

[dentdoc10]

I have one more question

which of the following teeth might possess 3 cusps?
1) max 2nd premolar and max 1st molar
2) max 2nd premolar and mand 1st premolar
3) max 1st molar and mand 2nd molar
4) max 2nd molar and mand 1st premolar
5) max 2nd molar and mand 2nd premolar

I think the way to solve this problem is to find teeth that has either +1 or -1 from 3 cusps since 1cusp or 5cusp will have less chance of having 3 cusps.
The correct answer is 5) max 2nd molar and mand 2nd premolar.

I think max 2nd molar has 4 cusps and mand 2nd premolar has 2 cusps.
But, how about 4) max 2nd molar and mand 1st premolar?
I thought all anterioer teeth have 1 cusp, all premolars have 2 cusps, max 1st molar has 5 cusps (or is 4 normal and cusp of carabelli abnormal?).

I am confused. Please help me~

Ans- 5) max 2nd molar and mand 2nd premolar
In this Q, Molar's with Premolars r being compared.
When it comes to premolars, the only tooth with 3 cusps will be the mand 2nd premolar -Y type -most common type. Now, this narrows down to only 1 ans choice i.e the 5th choice. DL cusp of Max 2nd M is the smallest/absent - so, Max 2nd M can have 3cusps
[DL cusp decreases in size from Max 1st M to 3rd M where its absent. So,Max 3rd M with 3 cusps can be an obvious ans choice (not included in the above Q)]

 

[dentdoc10]

Decks Biochem Card 62 says that the van der Waals interactions between stacked bases in DNA are the strongest non covalent forces in the double helix. Aren't H bonds stronger???

The 2 forces that stabilize the double helix are the -H bond b/w base pairs and the base stacking interactions.
All inter-molecular forces are generally categorized as Van der waals forces. H bond, a type of Van der waals force, is the strongest amongst them. But the collective base stacking interaction b/w the parallelly aliened bases is especially strong allowing the bases to arrange themselves like a stack of coins and keeping them that way.

 

[Hopeless101]

Dentdoc10,
I agree with you that there are two types of maxillary second molars found occlusally the rhomboidal outline form (four cusp type)which resembles the First Molar and the heart-shaped(three-cusp type) with poorly developed distolingual cusp (sometimes even it is absent) that looks like a third molar...

 

[Hatico]

Which of the following is TRUE of bacteriophages?
A. There are three pathways of replication.
B. The lytic cycle includes a prophage.
C. The host cell is not destroyed in the lysogenic
cycle.
D. They are viruses.
E. DNA is incorporated into the host-cell
chromosome in the lytic cycle

C is correct. Why C only?
Phage's DNA is incorporated into the host chromosome in both the lytic ( for replication and cell death ) and the lysogenic ( change bacterial phenotype ) cycle.
My answers B,C,D,E


Each of the following is a possible cause of disseminated
intravascular coagulation EXCEPT
A. major trauma.
B. malignancy
C. gram-negative sepsis.
D. amniotic fluid embolism.
E. type I hypersensitivity reaction.

E is correct. Why? Shock cause DIC-syndrome.

Someone can explain?

 

[Hopeless101]

This is from my class lecture notes "DIC occurs as a complication of many disease states, most notably Gram-negative sepsis - endotoxin effect. Also obstetric complications, metastatic cancer, extensive trauma - all associated with extensive tissue necrosis.
Clotting factors become activated inside the blood vessels due to endotoxins released by the bacteria and a disseminated consumption of clotting factors is produced; as a consequence, the patient starts bleeding through mucosae, skin and blood internal vessels. The presence of fibrin split products in the blood is diagnostic of DIC"

Virulence factor undergo only the lytic cycle......Phage DNA replicate in the lytic phase and eventually cell lysis occurs...in the lysogenic phase integration of phage DNA occurs (No lysis though)

Maybe Someone else can explain better?

 

[Hatico]

Thank you for explanation.
Shock causes sludge-syndrome and DIC that eventually cause cells and organs death. Still not sure this answer is correct(

The activities of each of the following EXCEPT one contribute to calculus formation. Which one is this EXCEPTION?

1. Alkaline phosphatase
2. Acid phosphatase
3. Pyrophophatase
4. Collagenase
5. Esterase

1 or 4? I think collagenase decreases calculus formation

 

[DancingKoala]

Q1. I have a question about # of cusps on molars.
My dental deck says mand molars got 5 and max molars got 4 cusps.
However, this isn't always true.
mand 1st molar got 5 but mand 2nd got 4.
Max 2nd molar got 4 but max 1st got 5 (cusp of carabelli).
Could someone explain this to me?



Q2.
dental deck says Cementum composition = 50% inorganic, 40%organic, and 10% water
but my other sources says
65+23+12
Also, dental deck says enamel has 96% inorganic, 1% oraganic, 3% water whereas
my other source says 96% inorganic and 4% inorganic.
which one is correct?


Q3. where is coronal?
anatomical enamel = coronal to the cervical third. So this sounds like coronal is the tip of the cusp
But then dental deck says aceullar cementum is coronal 2/3 of the root and cellular is apical third of the root. This sounds like coronal is location below cervical line.
I am confused.

 

[Hatico]

1.
3, 14 - 4 cusps. Carabelli is additional enamel formation - not a cusp.
2, 15 - 3to 4 cusps
19, 30 - 5 cusps
18, 31 - 4 cusps

2. all of them are correct

3.
coronal ( or cervical ) 1\3 of the root - acellular cementum
middle 1\3 of the root - acellular
apical 1\3 of the root - cellular

 

[dentdoc10]

Thank you for explanation.
Shock causes sludge-syndrome and DIC that eventually cause cells and organs death. Still not sure this answer is correct(

The activities of each of the following EXCEPT one contribute to calculus formation. Which one is this EXCEPTION?

1. Alkaline phosphatase
2. Acid phosphatase
3. Pyrophophatase
4. Collagenase
5. Esterase

1 or 4? I think collagenase decreases calculus formation

Shock does cause Sludge syndrome and DIC
In the compensatory phase of shock, the body tries to restore the body's equilibrium, by increasing the sympathetic response of the body. But if the conditions that led to shock persists, then the body goes to the progressive phase of shock, giving rise to all the symptoms of SLUDGE syndrome due to lack of sympathetic response/stimuli or due to increase parasympathetic response. Physical injury,chemical injury or sepsis causes endothelial cell injury. This decreases endothelial synthesis of anticoagulant factors which normally prevent clotting within the circulation. Micro thrombi formation & SLUDGE causes increased capillary permeability, loss of blood volume, slowing of microcirculation, ischemia, increased metabolic acidosis, decreased perfusion, cell & organ death.

Ans: 1) Alkaline phosphatase

 

[sweetsmile1]

What is the maximum number of amino acids that can be coded for by a polynucleotide which contains only adenine, uracil and cytosine?
a) 9
b) 64
c) 20
d) 27
e) 3

The answer is d) 27

Can anybody plz explain the way to solve this problem?

 

[Hatico]

c

 

[Hatico]

exponental algebra! 3*3*3 = 27
27 variation for 3nucleotide sequence or 27 virtual amino acids
( for example, for 6 different virtual nucleotides, 6*6*6*6*6*6 sequences, but practically only 4 nucleotides were discovered - it does not work )

hope that you got it

 

[DancingKoala]

The contact areas of anterior teeth are incisal to the middle thirds in each of the following except one. Which one is this exception?
A. distal contact of the max canine
B. mesial contact of the max canine
C. mesial contact of max lateral incisor
D. mesial contact of the mand lateral incisor
E. distal contact of the mand lateral incisor

I think that
A = Middle 3rd
B = junction
C,D,E = incisor 3rd

However, the answer is A.
Does this mean I was wrong thinking that A is middle 3rd ?
when the question asks incisal to the middle third, it's including incisal, junction, and middle third right? So then the correct answer should be the one with cervical third? right?








Here is another one.
To properly align the max central incisor and the max lateral incisor, the orthodontist will ensure that the distal surface of the max central incisor contacts what area of the mesial surface of the max lateral incisor?
answer = incisor third.

However, the dental deck says the contact area between max central and lateral should be at the junction between incisor and middle third. NOT the incisal third.

 

[dentdoc10]

Q1. I have a question about # of cusps on molars.
My dental deck says mand molars got 5 and max molars got 4 cusps.
However, this isn't always true.
mand 1st molar got 5 but mand 2nd got 4.
Max 2nd molar got 4 but max 1st got 5 (cusp of carabelli).
Could someone explain this to me?



Q2.
dental deck says Cementum composition = 50% inorganic, 40%organic, and 10% water
but my other sources says
65+23+12
Also, dental deck says enamel has 96% inorganic, 1% oraganic, 3% water whereas
my other source says 96% inorganic and 4% inorganic.
which one is correct?


Q3. where is coronal?
anatomical enamel = coronal to the cervical third. So this sounds like coronal is the tip of the cusp
But then dental deck says aceullar cementum is coronal 2/3 of the root and cellular is apical third of the root. This sounds like coronal is location below cervical line.
I am confused.

Regarding the composition, I would stick with Decks.

Tooth is divided into crown - cervical line to incisal edge/cusp tip and root -cervial line to root tip. Coronal means towards the crown and apical means towards the root....used as directional terms. Moving up,the crown is divided into cervical 3rd, middle 3rd and incisal 3rd/occlusal 3 rd... same with the root, going down, into cervical 3rd, middle 3rd and apical 3rd. So,
*coronal to cervical 3rd means above cervical 3rd i.e. the area b/w the junction of cervical 3rd to the incisal edge/ cusp tip.
*coronal 2/3rd of root means - junc of apical and middle 3rd to cervial line and apical 3rd of root means - junction of apical and middle 3rd to root tip.

R u a FTD?

 

[DancingKoala]

Each of the following is expected to be active during fatty acid biosynthesis except?
A. TCA cycle
B. pyruvate dehydrogenase
C. AA catabolism
D. beta oxidation
E. glycolysis.

The answer is D. Could you explain to me why each of them are correct/incorrect?






A patient with hep C is scheduled for extraction of posterior teeth in the right lower quadrant due to advanced periodontal disease. Tooth #28 is abscessed and draining into medial soft tissue. Tooth #30 shows a large carious lesion and is painful

What is the most likely outcome of this patient's hep C?

answer = development of chronic hepatitis
There was another choice that says "development of hepatocellular carcinoma". Why can't this be the answer instead?

 

[Hatico]

What is the most likely outcome of this patient's hep C?

answer = development of chronic hepatitis
There was another choice that says "development of hepatocellular carcinoma". Why can't this be the answer instead?

common complication - fibrosis . only small amount of people may develop HC carcinoma. hepatocellular carcinoma is incorrect answer.

 

[DancingKoala]

During swallowing, muscular contraction results in movements that seal off the oropharynx from the nasopharynx. Which of the following muscles cause movements that result in a fold in the posterior wall of the pharynx?
a. levator veli palatini
b. tnsor veli palatini
c. palatopharygeus

The correct answer is C. palatopharyngeus.
I don't understand why A and B can't be the correct answers.

another old board question said
- Tensor veli palatini and levator veli palatini are two muscles that prevent food from entering the nasopharynx during swallowing.
which sounds like A and B should also be correct.





Each of the follwoing muscles receives motor innervation from the ansacervicalis except one. which one is the exception?
A. omohyoid
B. thyrohyoid
C. geniohyoid
D. sternohyoid
E. sternothyroid.

The correct answer is C. But I think B is also the correct answer.





Which of the following nerves is not located in the wall fo the cavernous sinus?
1. abducens
2. maxillary
3. trochlear
4. ophthalmic
5. oculomotor
the correct answer is 1. But I think the correct answer should be 2. Maxillary.

All of these are from the old boards. Can the boards be wrong?