Lets discuss questions of NBDE 1

[d dimps]

---

Members do not see this ad.

1). .Which angle does a P Wave makes on ECG?
a). .45 degree
b). .180 degree
c). .0 degree
d). .-45 degree
e). .-180 degree.

2). .What is endogenous cholesterol? Most endogenous cholesterol is converted to?
a). .Glucose
b). .Cholic acid
c). .Steroid
d). .Oxaloacetete
e). .Ketone bodies

3). .Which of the following statement is correct regarding Glioblastoma multiforme?
a). .the tumor is most common before puberty
b). .it is classified as a type of meningioma
c). .it is most common type of Astrocytoma.
d). .Its prognosis is generally more favourablethan Grade 1 astrocytoma.
e). .It is derived from the epithelial lining of ventricles

4). .Which of the following pathological changes is irreversible?
a). .fatty changes in liver cells
b). .karyolysis in myocardial cells
c). .glycogen deposition in hepatocyte nuclei
d). .hydropic vacuolization of renal tubular epithelial cells.

5). .An example of Synergism is the effect of?
a). .insulin and glucagon on blood glucose
b). .estrogen and progesterone on uterine motility
c). .growth hormone and thyroxine on skeletal growth.
d). .Antidiuretic hormone and aldosterone on potassium excretion.

 

[bratdoc]

thank u👍

Transfer of amino grps---transamination
release of ammonia-----oxidative deamination (most rapid in Glutamate)

 

[teethie]

ok i see. thanks a lot👍

Transfer of amino grps---transamination
release of ammonia-----oxidative deamination (most rapid in Glutamate)

 

[bratdoc]

What is the function of Macula densa cells?
Do they detect fall in BP to stimulate JG cells??

 

[wdent]

Macula densa
What i remeber it Sense Increase load (of increase renal pr) and cause CONSTICTION of nearby afferent arteriole----------->leads to increase resistance to maintain constant bld flow

 

[teethie]

No, macula densa cells monitors tubular composition and mediates renin release.

Decreased sodium chloride delivery past macula densa cells​

​

​

​

​

in the
thick ascending limb of the loop of Henle increases renin release.​

The​

​

​

​

juxtaglomerular cells, located in the walls of the afferent glomerular
arteriole, respond as baroreceptors and secrete renin in response to​

changes in perfusion pressure

ref:usmle physiology

What is the function of Macula densa cells?
Do they detect fall in BP to stimulate JG cells??

 

[wdent]

It also control Renin release by relying info about Na.

 

[bratdoc]

No, macula densa cells monitors tubular composition and mediates renin release.

Decreased sodium chloride delivery past macula densa cells​

​

​

​

​

in the
thick ascending limb of the loop of Henle increases renin release.​

The​

​

​

​

juxtaglomerular cells, located in the walls of the afferent glomerular
arteriole, respond as baroreceptors and secrete renin in response to​

changes in perfusion pressure

ref:usmle physiology

Thank you so much Wdent and Teethie!!👍

 

[dentistk]

In an ideal intercuspal position, the tip of the mesiolingual cusp of a permanent mandibular second molar

1. contacts the mmr of the max. second molar and distal marginal ridge of the max. first molar
2. occludes with the central fossa of the max. second molar
3. rests in the lingual sulcus of the max. second molar
4. none of the above

 

[dentistk]

In an ideal intercuspal position, the tip of the mesiolingual cusp of a permanent mandibular second molar

1. contacts the mmr of the max. second molar and distal marginal ridge of the max. first molar
2. occludes with the central fossa of the max. second molar
3. rests in the lingual sulcus of the max. second molar
4. none of the above

Ques74 from asda I-E DA, ans is 4... ...and the actual ans - opposes the lingual embrasure between the max. first and second molars. (ref-kaplan)

 

[Svetlana]

Some doubts.

When viewed from the mesial, a line bisecting the apex and root of the max.canine
1.also bisect the cusp tip
2.passes facial to cusp tip
3.passes lingual - ans

But as i understood max.canine's tip is straight and mand.canine tilts lingually.
?????????????????

Which of the following marginal ridges have little or no contact in ideal centric and eccentric maxillomandibular contact relationship?
ans : distal of mand.1PM+distal of mand.2PM+mesial of mand.1PM

Why???

 

[Svetlana]

Ques74 from asda I-E DA, ans is 4... ...and the actual ans - opposes the lingual embrasure between the max. first and second molars. (ref-kaplan)

Was dealing with this Q yesterday.
I suppose that cusp TIP will not occlude with anything.
???????

 

[Cindrella]

Good morning all ...

i wanted to clarify the lining of TMJ so i'm attaching this diagram which i created . Please pardon me if i have missed out on any essential anatomical structures around that area ....

The area lined in green is the fibrocartilage right ??? or synonymously fibrous connective tissue ???

the area lined in red is __________ ??? is it hyaline cartilage ??

the are lined in blue is ___________ ????



i know its a basic question but i am not sure of my understanding is right ... please help !!

 

[Svetlana]

Am i right?
Salpingopharyngeus muscle is innervated by accessory nerve,carried by vagus?

 

[pb2007]

Some doubts.

When viewed from the mesial, a line bisecting the apex and root of the max.canine
1.also bisect the cusp tip
2.passes facial to cusp tip
3.passes lingual - ans

But as i understood max.canine's tip is straight and mand.canine tilts lingually.
?????????????????

Which of the following marginal ridges have little or no contact in ideal centric and eccentric maxillomandibular contact relationship?
ans : distal of mand.1PM+distal of mand.2PM+mesial of mand.1PM

Why???

here's what i found in wheelers for max canine
a line bisecting the cusp is labial to a line bisecting the root .lines bisecting roots of central and lateral incisors also bisect the incisal ridges.
although i cant understand what first sentence is saying ,i hop[e it makes sense to u ,plz explain if u understand .

 

[pb2007]

Am i right?
Salpingopharyngeus muscle is innervated by accessory nerve,carried by vagus?

innervated by vagus nerve via pharengeal plexus

 

[pb2007]

Good morning all ...

i wanted to clarify the lining of TMJ so i'm attaching this diagram which i created . Please pardon me if i have missed out on any essential anatomical structures around that area ....

The area lined in green is the fibrocartilage right ??? or synonymously fibrous connective tissue ???

the area lined in red is __________ ??? is it hyaline cartilage ??

the are lined in blue is ___________ ????



i know its a basic question but i am not sure of my understanding is right ... please help !!

i think u r rite with the first point ,dont tkno abt the rest .

 

[teethie]

thank u pb2007 for the reference.👍

here is what it means:
if u draw a line from the cusp tip to cervical line(only first think in coronal portion) then this line is lying labial to the line which is bisecting the root tip till the cervical line(now only think of root portion)

now look at the question:
When viewed from the mesial, a line bisecting the apex and root of the max.canine will passes lingual - hence the ans

hope this is clear.

here's what i found in wheelers for max canine
a line bisecting the cusp is labial to a line bisecting the root .lines bisecting roots of central and lateral incisors also bisect the incisal ridges.
although i cant understand what first sentence is saying ,i hop[e it makes sense to u ,plz explain if u understand .

 

[pb2007]

thank u pb2007 for the reference.👍

here is what it means:
if u draw a line from the cusp tip to cervical line(only first think in coronal portion) then this line is lying labial to the line which is bisecting the root tip till the cervical line(now only think of root portion)

now look at the question:
When viewed from the mesial, a line bisecting the apex and root of the max.canine will passes lingual - hence the ans

hope this is clear.

thanku so much teethie ,i understood it now,so it means that with respect to the root tip the cusp tip is placed labially .for mandibular the line should pass labially coz cusp tip of mandibular canine is lingual.am i rite??

 

[teethie]

yes, u r right for max illary canine. but for mand canine, i can not confirm unless i read it from somewhere because see this is anatomy, like max canine cusp is straight but see the anatomy is so unique that its tip lies labially when we bisect it in respect to root.

i can only confirm once i check it or smeone post some reference. please give me some time to find out.

thanku so much teethie ,i understood it now,so it means that with respect to the root tip the cusp tip is placed labially .for mandibular the line should pass labially coz cusp tip of mandibular canine is lingual.am i rite??

 

[teethie]

agree with pb2007👍

cindrella: no idea about the lining of other areas. but if fibrocartilage is not there then periosteum makes sense. did not read anywhere so far👎

i think u r rite with the first point ,dont tkno abt the rest .

 

[pb2007]

yes, u r right for max illary canine. but for mand canine, i can not confirm unless i read it from somewhere because see this is anatomy, like max canine cusp is straight but see the anatomy is so unique that its tip lies labially when we bisect it in respect to root.

i can only confirm once i check it or smeone post some reference. please give me some time to find out.

thanks teethie,
here wht i found abt the mesial aspect of mandibular canine frm wheelers [pg192}
the tip of cusp is more nearly centered over the root,with a lingual placement in some cases comparable to the placement of incisal ridges on mandibular incisors .

 

[teethie]

yes svetlana , it is not occluding anywhere. answer there is none of the above.
other sdner has only mentioned the position where the mesiolingual cusp tip will lie.

Was dealing with this Q yesterday.
I suppose that cusp TIP will not occlude with anything.
???????

 

[bratdoc]

Hi everyone
can u tell me insulin secreted from the pancreas as?
Preproinsulin
Proinsulin
Insulin
and also which which of these is present where

 

[pb2007]

Hi everyone
can u tell me insulin secreted from the pancreas as?
Preproinsulin
Proinsulin
Insulin
and also which which of these is present where

Proinsulin is the prohormone precursor to insulin made in the beta cells of the islets of Langerhans, specialized regions of the pancreas. In humans, proinsulin is encoded by the INS gene

Proinsulin is synthesized in the endoplasmic reticulum, where it is folded and its disulfide bonds are oxidized. It is then transported to the Golgi apparatus where it is packaged into secretory vesicles, and where it is processed by a series of proteases to form mature insulin. Mature insulin has 35 fewer amino acids; 4 are removed altogether, and the remaining 31 form the C-peptide. The C-peptide is abstracted from the center of the proinsulin sequence; the two other ends (the B chain and A chain) remain connected by disulfide bonds.
http://en.wikipedia.org/wiki/Proinsulin
http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/pancreas/insulin.html

 

[teethie]

i would say insulin.
read this
http://books.google.ca/books?id=iyQ... the form of proinsulin preproinsulin&f=false

in this i was able to make out where preproinsulin is synthesised but do u know where pronsulin will be formed.???

Hi everyone
can u tell me insulin secreted from the pancreas as?
Preproinsulin
Proinsulin
Insulin
and also which which of these is present where

 

[Svetlana]

thank u pb2007 for the reference.👍

here is what it means:
if u draw a line from the cusp tip to cervical line(only first think in coronal portion) then this line is lying labial to the line which is bisecting the root tip till the cervical line(now only think of root portion)

now look at the question:
When viewed from the mesial, a line bisecting the apex and root of the max.canine will passes lingual - hence the ans

hope this is clear.

Teethy!!!
You are genius!!!!!!
Thanks a lot!!!

 

[teethie]

awesome, pb2007😍

i found the same in wheelers, but u already posted the text. so there r channces that it is centred also and some cases lingually also.
see i told u anatomy is unique in so many things.

thanks teethie,
here wht i found abt the mesial aspect of mandibular canine frm wheelers [pg192}
the tip of cusp is more nearly centered over the root,with a lingual placement in some cases comparable to the placement of incisal ridges on mandibular incisors .

 

[teethie]

it is only everyone;s questions that can make me genius otherwise i am an average person only.

Teethy!!!
You are genius!!!!!!
Thanks a lot!!!

 

[Svetlana]

To add some points to your insulin discussion.
When proinsulin is cleaved it yields insulin+C protein.
On the basis of this protein we can figure out if HYPOGLYCEMIA is due to insulinoma(high C protein) or selfinjection with insulin( normal C protein)

 

[bratdoc]

Proinsulin is the prohormone precursor to insulin made in the beta cells of the islets of Langerhans, specialized regions of the pancreas. In humans, proinsulin is encoded by the INS gene

Proinsulin is synthesized in the endoplasmic reticulum, where it is folded and its disulfide bonds are oxidized. It is then transported to the Golgi apparatus where it is packaged into secretory vesicles, and where it is processed by a series of proteases to form mature insulin. Mature insulin has 35 fewer amino acids; 4 are removed altogether, and the remaining 31 form the C-peptide. The C-peptide is abstracted from the center of the proinsulin sequence; the two other ends (the B chain and A chain) remain connected by disulfide bonds.
http://en.wikipedia.org/wiki/Proinsulin
http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/pancreas/insulin.html

Thank you Pb2007, Teethie and Svetlana!
So it means that:
Preproinsulin--- first translation product by INS gene
Proinsulin----ER product
INsulin----final product released from Beta cells
is this correct?
@Svetlana: excellent point regarding C-peptide!!

 

[teethie]

svetlana: thanks a lot.


bratdoc: see below

Thank you Pb2007, Teethie and Svetlana!
So it means that:
Preproinsulin--- first translation product by INS gene-----: not coded by INS gene, it is preinsulin. prepronsulin syntheisis is occuring in cytoplasm.

http://books.google.ca/books?id=hgiuDHVUuT4C&lpg=PA27&dq=insulin%20%20the%20form%20of%20proinsulin%20preproinsulin&pg=PA27#v=onepage&q=insulin%20%20the%20form%20of%20proinsulin%20preproinsulin&f=false

Proinsulin----ER product
INsulin----final product released from Beta cells
is this correct?
@Svetlana: excellent point regarding C-peptide!!

 

[pb2007]

can anyone explain in simple words the difference between allosteric inhibition n non compititive inhibition ,i fail to understand this .i hav put up this doubt before too n anniemirza came up with a gud link too but i'm still not getting it rite .

 

[bratdoc]

svetlana: thanks a lot.


bratdoc: see below

hmmm..
Teethie can you please explain the order of production and location in a sequence?? i did not get it!!😕

 

[teethie]

pb2007, i am looking into ur ques also.


here u go:

1) Preproinsulin--- syntheisis is occuring in cytoplasm same way like trnscription and translaton processes occur for any other protein.

2)Proinsulin----. actually what happens is signal peptidase is removed from prepronsulin and then proinsulin is formed. itis happening in ER.

3) INsulin----. proinsulin cleaves into insulin. this is happening in golgi apparatus. final product is insulin released from Beta cells.

hmmm..
Teethie can you please explain the order of production and location in a sequence?? i did not get it!!😕

 

[bratdoc]

pb2007, i am looking into ur ques also.


here u go:

1) Preproinsulin--- syntheisis is occuring in cytoplasm same way like trnscription and translaton processes occur for any other protein.

2)Proinsulin----. actually what happens is signal peptidase is removed from prepronsulin and then proinsulin is formed. itis happening in ER.

3) INsulin----. proinsulin cleaves into insulin. this is happening in golgi apparatus. final product is insulin released from Beta cells.

Thanks a lot!👍

 

[IMFdoc]

can anyone pls explain me what is the difference between lesion of left V1 nerve and right V1 nerve?

 

[elmos]

thks teethie for this awesome explanation on insulin
which of the following are part of the conducting division in the respiratory system:
primary bronchus
terminal bronchiole
respiratory bronchiole
i'm confused here can anyone clarify pls.

 

[teethie]

hi pb2007, ur confusion is genuine because they have got the similarities and very few differences exist in mechanics only. see below.

Both allosteric regulators and non-competitive inhibitors act in the same way in that they both effect enzyme activity by binding to the enzyme at a site which is NOT the active site. As a result of the binding of the allosteric regulator or non-competitive inhibitor, the enzyme undergoes a conformational change which effects the binding of the substrate to the active site.
However, there are two important differences :

1.Allosteric regulators are always reversible. They regulate important pathways in cells so they are reversible.
Non-competitive inhibitors, on the other hand, are usually irreversible.

2.Allosteric regulators can be positive as well as negative regulators. binding of some allosteric regulators can actually serve to INCREASE the rate of a particular reaction.
Non-competitive inhibitors always act to DECREASE the rate of a reaction - they cannot increase enzyme activity.

can anyone explain in simple words the difference between allosteric inhibition n non compititive inhibition ,i fail to understand this .i hav put up this doubt before too n anniemirza came up with a gud link too but i'm still not getting it rite .

 

[teethie]

elmos, these kind of questions always lead to confusion but they are not asda questions. and we dont know if the framing of question is right or no. so go with the concept always.

primary bronchus
terminal bronchiole
both are parts of conducting division.

thks teethie for this awesome explanation on insulin
which of the following are part of the conducting division in the respiratory system:
primary bronchus
terminal bronchiole
respiratory bronchiole
i'm confused here can anyone clarify pls.

 

[wdent]

Preproinsulin in RER

 

[elmos]

thks teethie.
i'm so confused when i see these questions.

 

[pb2007]

hi pb2007, ur confusion is genuine because they have got the similarities and very few differences exist in mechanics only. see below.

Both allosteric regulators and non-competitive inhibitors act in the same way in that they both effect enzyme activity by binding to the enzyme at a site which is NOT the active site. As a result of the binding of the allosteric regulator or non-competitive inhibitor, the enzyme undergoes a conformational change which effects the binding of the substrate to the active site.
However, there are two important differences :

1.Allosteric regulators are always reversible. They regulate important pathways in cells so they are reversible.
Non-competitive inhibitors, on the other hand, are usually irreversible.

2.Allosteric regulators can be positive as well as negative regulators. binding of some allosteric regulators can actually serve to INCREASE the rate of a particular reaction.
Non-competitive inhibitors always act to DECREASE the rate of a reaction - they cannot increase enzyme activity.

thanks a tonn teethie for all your effort .this topic was bothering me frm a long time .👍

 

[Cindrella]

@ pb2007 - thanks for confirming the fibrocartilage part .

@teethie - great explanation on insulin , proinsulin and preproinsulin

questions and discussions on this thread scare me 🙁 ... but the answers enlighten me ! so thank you all 👍

 

[Svetlana]

1.mand.foramen below/above occlusal plane of molars?
2.incisive foramen can be divided to a)foramina of Stenson b)foramina of Scarpa(occasionally,for nasopalatine nerves)?

Found it in my notes.Not sure if it's true.

 

[Cindrella]

1.mand.foramen below/above occlusal plane of molars? it is above and posterior to the occlusal plane. There is an error in decks.
2.incisive foramen can be divided to a)foramina of Stenson b)foramina of Scarpa(occasionally,for nasopalatine nerves)?

Found it in my notes.Not sure if it's true.

Immediately behind the incisor teeth is the incisive foramen .In this foramen are 2 lateral apertures , the opening of the incisive canal ( f. of stenson ) which transmit branches of the 1) sphenopalatine artery and 2) nasopalatine nerves
2 additional canals are present. They are termed the F. of scarpa ( in the midline ) . they transmit nasopalatine nerves.

from decks

 

[dentistk]

Good morning all ...

i wanted to clarify the lining of TMJ so i'm attaching this diagram which i created . Please pardon me if i have missed out on any essential anatomical structures around that area ....

The area lined in green is the fibrocartilage right ??? or synonymously fibrous connective tissue ???

the area lined in red is __________ ??? is it hyaline cartilage ??

the are lined in blue is ___________ ????



i know its a basic question but i am not sure of my understanding is right ... please help !!

The green area is Fibrocartilage http://www.dustinnelsondds.com/images/TMJ.jpgk"][/URL]"] (ref)

The nature of articular disc - fibrocartilage
articular disk - a pad of fibrocartilage or dense fibrous tissue present in some synovial joints.http://medical-dictionary.thefreedictionary.com/articular+disk[/URL][ref]

Blue, Red, and Cyan Lines - should be Periosteum 'cause I checked for references that explained otherwise, couldn't find anything.

Hope that helps.

 

[Svetlana]

Immediately behind the incisor teeth is the incisive foramen .In this foramen are 2 lateral apertures , the opening of the incisive canal ( f. of stenson ) which transmit branches of the 1) sphenopalatine artery and 2) nasopalatine nerves
2 additional canals are present. They are termed the F. of scarpa ( in the midline ) . they transmit nasopalatine nerves.

from decks

Thanks!!!
Do not really have time searching!
Its very helpful!!

 

[Svetlana]

Can somebody put ALL kinds of epithelium related to salivary gland???
Coz in dif.parts they are different.

 

[Cindrella]

The green area is Fibrocartilage http://www.dustinnelsondds.com/images/TMJ.jpgk"][/URL]"] (ref)

The nature of articular disc - fibrocartilage
articular disk - a pad of fibrocartilage or dense fibrous tissue present in some synovial joints.http://medical-dictionary.thefreedictionary.com/articular+disk[/URL][ref]

Blue, Red, and Cyan Lines - should be Periosteum 'cause I checked for references that explained otherwise, couldn't find anything.

Hope that helps.

Thanks a lot dentistk .... yeah it should be periosteum only but i think i came across hyaline cartilage being mentioned somewhere . But, i can't recollect where from ... so till i find a definite reference for that , will consider it to be periosteum only 🙂

Thank you.

Sorry , another question... where is synovial membrane present on the TMJ ??? was that the red part ???

 

[nbdeaspirant1]

1. Yes, if you give your exam in feb 2011, you comfortably can apply for admissions throughout 2011..
2. From what I heard, NBDE scores are valid for 5 years. But some people with scores dating even before that have also applied. Really don't know how that went.
3. Yes you will need to repeat the TOEFL again as the scores are valid for 2 years, and a valid score will only be accepted at the time of admission. That is why I also gave my exam again!! Also, most people recommend you give the TOEFL after your NBDE exam.

There are many more experienced people on this forum who can guide you much better with the application procedures. Catch hold of one of them!😛

thanks a ton!!!!