Celluar components originating from endosymbionts organisms living

Question

Celluar components originating from endosymbionts organisms living within organisms, are the result of the endosymbiont becoming dependent on its host. Organelles, components of cells with specialized functions, originated from bacterial endosymbionts if they have their own separate DNA.

If mitochondria, components of most eukaryotic cells, originated from bacterial endosymbionts, then it can be inferred that

A. Mitochondria have their own separate DNA.

B. Mitochondria are a kind of organelle.

C. Some bacterial endosmbionts became dependet on their cellular hosts.

D. Mitochondria are the only organelles with their won separate DNA.

E. DNA is the result of endosmbionts becoming dependent on their hosts.

Source : 800Score

chetan2u · Answer

Main points  
1. CC originating from Endo are result of Endo becoming dependent on its host..
2. If organelles have separate DNA , they have originated from B Endo.
3. If M originated from B Endo..??

Let us see the choices..

A. Mitochondria have their own separate DNA.
 point 2 :- If A then B. And this choice is If B then A

B. Mitochondria are a kind of organelle.
 There is no connection between M and organelle

C. Some bacterial endosmbionts became dependent on their cellular hosts.
 M originated from B Endo and point 1 says they are result of Endo becoming dependent on their host. So this must be true. CORRECT

D. Mitochondria are the only organelles with their won separate DNA.
  Nothing says so in the para

E. DNA is the result of endosmbionts becoming dependent on their hosts.
  DNA are nowhere shown to be connected to Endo becoming dependent on their hosts

C

BoundMan · Answer

VeritasKarishma  Hello Karishman, I still cannot see why A is wrong.
 chetan2u  If we reject A by - If A then B. And this choice is If B then 
Then the same should apply for C no?

TestPrepUnlimited · Answer

Correct answer: C.

A: Incorrect. It does not follow that mitochondria are organelles simply because they have originated from endosymbionts; cellular components other than organelles could have emerged from endosymbionts. 
B: Incorrect. It does not follow that mitochondria are organelles simply because they have originated from endosymbionts; cellular components other than organelles could have emerged from endosymbionts. 
C. Correct. Mitochondria --> cellular components --> originated from bacterial endosymbionts. Cellular components originating from bacterial endosymbionts --> result of the endosymbiont becoming dependent on the cellular hosts. Therefore, some endosymbionts have become dependent on their cellular hosts.
D. Incorrect. As in (A) and (B) it does not necessarily follow that mitochondria are organelles with their own separate DNA, and whether they are does not preclude other organelles with their own DNA existing. 
E. Incorrect. The argument only states that organelles with  their own DNA  are the result of endosymbionts, not that all DNA is.

KarishmaB · Answer

First of all, the way the argument is written is not good. It needs to be written clearly.

Cell components originate from endo organisms when endo organism becomes dependent on its host. 
Organelles are components of cells with specialized functions.
Organelles, if they have their own separate DNA, originated from bacterial endosymbionts.

If mitochondria (cell components) originated from bacterial endosymbionts - 
So we know that mitochondria originated from bacterial endosymbionts. So these bacterial endosymbionts must have become dependent on their host.
Also, can we say whether mitochondria have their own separate DNA? No. First of all, we don't know if they are organelles (cell components with specialised functions). Secondly, even if we did know that they are organelles, we that that organelles which have their own DNA originated from endosymbionts. But can we say that all organelles which originated from endosymbionts have their own DNA? No.
In "If A, then B" statements, 'A implies B' but 'B does not imply A'.

A. Mitochondria have their own separate DNA.

Cannot say.

B. Mitochondria are a kind of organelle.

Cannot say.

C. Some bacterial endosmbionts became dependet on their cellular hosts.

Yes, this must be true.

D. Mitochondria are the only organelles with their won separate DNA.

Cannot say.

E. DNA is the result of endosmbionts becoming dependent on their hosts.

Cannot say.

Answer (C)

krndatta · Answer

KarishmaB  ma'am,

What is wrong with my inference. I inferred 
"If organelles originated from bacterial endo, they have their own separate DNA".

The final part of the argument mentions "Organelles originated from endo, if they have their own separate DNA"

How is the original inference the opposite of the above?

Please clarify.

Thanks

KarishmaB · Answer

Note what is the "if clause" and what is the "then clause". Which clause is written first is irrelevant. We can write "If A, then B" or we can write "B, if A". Both mean exactly the same.

Original statement:
 Organelles, components of cells with specialized functions, originated from bacterial endosymbionts if they have their own separate DNA.
 
It means: If they have their own separate DNA, then they originated from bacterial ES.

"own DNA" is the if clause.

If own DNA, then from bacterial ES.

Your inference is the opposite of this.

Raman109 · Answer

Understanding the argumnent - 
Celluar components originating from endosymbionts organisms living within organisms, are the result of the endosymbiont becoming dependent on its host. - Fact. 
Organelles, components of cells with specialized functions, originated from bacterial endosymbionts if they have their own separate DNA. -Fact

The sufficient conditional is - If they have their own separate DNA, then Organelles originated from bacterial endosymbionts. 
If A, then B means
A implies B 
Not B implies not A

But B implies A is not true - saying Organelles originated from bacterial endosymbionts, they have their own separate DNA - is wrong. This is what options A and B confuse.

If mitochondria, components of most eukaryotic cells, originated from bacterial endosymbionts, then it can be inferred that

A. Mitochondria have their own separate DNA. -Distortion.

B. Mitochondria are a kind of organelle. - We don't even know if "mitochondria" are "Organelles." Distortion.

C. Some bacterial endosymbionts became dependent on their cellular hosts. - ok

D. Mitochondria are the only organelles with their own separate DNA. - Distortion. Pick the word "Mitochondria" from the question stem, "organelles," and DNA from the argument and create a tricky option. Distortion.

E. DNA is the result of endosymbionts becoming dependent on their hosts. - Out of scope.

Celluar components originating from endosymbionts organisms living

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Celluar components originating from endosymbionts organisms living

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