Please help me with this question

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sjkpark

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Q) Which of the following is correct?

1. Contraction of the ciliary muscle causes increased curvature of the lens.
2. The lens has the greatest refracting power of any element of the eye.
3. Posterior sub-capsular cataract is more common in diabetes mellitis.
4. Aqueous humour is secreted by the ciliary epithelium.
5. The lens continues to increase in cell numbers throughout life.

The answer the bloody computer gave me was 2. But I KNOW that's not true.
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sjkpark said:
Q) Which of the following is correct?

1. Contraction of the ciliary muscle causes increased curvature of the lens.
2. The lens has the greatest refracting power of any element of the eye.
3. Posterior sub-capsular cataract is more common in diabetes mellitis.
4. Aqueous humour is secreted by the ciliary epithelium.
5. The lens continues to increase in cell numbers throughout life.

The answer the bloody computer gave me was 2. But I KNOW that's not true.
Click to expand...

All is correct, except for answer #2. The cornea's air-tear film interface contributes to ~2/3 of the refracting power whereas the lens contributes ~1/3. Perhaps the question is written incorrectly?
 
sjkpark said:
Q) Which of the following is correct?

1. Contraction of the ciliary muscle causes increased curvature of the lens.
2. The lens has the greatest refracting power of any element of the eye.
3. Posterior sub-capsular cataract is more common in diabetes mellitis.
4. Aqueous humour is secreted by the ciliary epithelium.
5. The lens continues to increase in cell numbers throughout life.

The answer the bloody computer gave me was 2. But I KNOW that's not true.
Click to expand...

It seems like your question should read which of the following is NOT correct. I think they're all correct EXCEPT number 2.

Jenny
 
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Andrew_Doan said:
All is correct, except for answer #2. The cornea's air-tear film interface contributes to ~2/3 of the refracting power whereas the lens contributes ~1/3. Perhaps the question is written incorrectly?
Click to expand...

Yeah. that.

lol

:D

Jenny
 
Nope, I have the original copy of the paper with me. It's amazing how they have absolutely no idea what we've been taught; or how much effort has been put into assembling these questions (considering multiple spelling mistakes, etc.) :mad:

Here's another one.

Which of the following is incorrect:

1. The superior oblique muscle depresses the globe.
2. The superior oblique muscle is supplied by the fourth cranial nerve.
3. The actions of the oblique muscles change as direction of gaze changes.
4. Sixth cranial nerve palsy causes a vertical diplopia (double vision).
5. The medial rectus muscle is supplied by the third cranial nerve.

What do you think?
 
sjkpark said:
Nope, I have the original copy of the paper with me. It's amazing how they have absolutely no idea what we've been taught; or how much effort has been put into assembling these questions (considering multiple spelling mistakes, etc.) :mad:

Here's another one.

Which of the following is incorrect:

1. The superior oblique muscle depresses the globe.
2. The superior oblique muscle is supplied by the fourth cranial nerve.
3. The actions of the oblique muscles change as direction of gaze changes.
4. Sixth cranial nerve palsy causes a vertical diplopia (double vision).
5. The medial rectus muscle is supplied by the third cranial nerve.

What do you think?
Click to expand...

Number 4 is INcorrect. The sixth cranial nerve inervates the lateral rectus muscle. Palsies of this nerve cause horizontal diplopia.

Jenny
 
JennyW said:
Number 4 is INcorrect. The sixth cranial nerve inervates the lateral rectus muscle. Palsies of this nerve cause horizontal diplopia.

Jenny
Click to expand...

The computer says that the answer is 3!

It is very confusing. Can someone please explain to me re: actions of obliques? Don't their actions change depending on your gaze?
 
sjkpark said:
The computer says that the answer is 3!

It is very confusing. Can someone please explain to me re: actions of obliques? Don't their actions change depending on your gaze?
Click to expand...

The superior oblique muscle depresses, abducts, and causes incyclotorsion of the globe in primary gaze. When the eye is ADDucted 51 degrees, it causes depression only. (or the very least the incyclotorsion action is minimal)

6th cranial nerve palsies do not produce vertical diplopia. IMO, that is the correct answer to your question.

You might want to consider a different study aid.

Jenny
 
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