Regarding two statements made in the For Dummies Series

[Permanence]

Hi and thank you for clicking on my thread. I am currently planning to independently study introductory Biology. I ordered two reading supplements; a textbook and a short-reading "Biology For Dummies, 2nd Edition".

I did not expect great content in the book by Kratz, but I do expect the information to be valid. With-in the first fifty pages I came across two comments the author made that I do not agree with.
A. In her discussion of an atom she claimed that an electron does not have any mass. While I can recognize that the mass of an electron is very small, the claim that is non-existent goes against everything I've learned in my classical mechanics course. Who is in the wrong here? Is that a notion that is held in Bio 101 courses?
B. The author claimed that DNA is found in every single cell. I do not agree with that statement. I recall learning that DNA is not found in red blood cells. Once again, who is in the wrong here? Would that statement be correct in a Bio 101 course?

I've stopped reading the book entirely at this point, as I frankly do not feel comfortable reading something that may contain many errors. Could someone weigh in on this matter or perhaps, someone familiar with the text, provide me with some feed back?

With Regards,
Permanence

 

[phinds]

I can't comment on DNA but the "electron has no mass" statement is just silly. If the electron had no mass it would travel at light speed (in a vacuum)

 

[Permanence]

Thank you for your reply. Maybe I'm over-thinking this, but I'm really trying to find an explanation for why an author would make such a statement. Surly someone with a PhD in any scientific field should know something so elementary?

Hopefully someone with background in biology has some experience with this book, I'd love to hear what they have to say. I'm hesitant to keep reading the book, yet I'm also hesitant to throw out a new book.

 

[DiracPool]

Technically the electron is supposed to have no "size" as a point particle. Are you sure she didn't use size instead of mass? That would be a significant booboo if she said mass.

 

[SW VandeCarr]

B. The author claimed that DNA is found in every single cell. I do not agree with that statement. I recall learning that DNA is not found in red blood cells. Once again, who is in the wrong here? Would that statement be correct in a Bio 101 course.

Erythrocytes (red blood cells or RBCs) do have nuclei in their younger stages in the bone marrow, but in mammals, the mature forms no longer have nuclei. They do not reproduce in the blood stream and are destroyed in the spleen after about 120 days.

 

[phinds]

Thank you for your reply. Maybe I'm over-thinking this, but I'm really trying to find an explanation for why an author would make such a statement. Surly someone with a PhD in any scientific field should know something so elementary?

Hopefully someone with background in biology has some experience with this book, I'd love to hear what they have to say. I'm hesitant to keep reading the book, yet I'm also hesitant to throw out a new book.

Well, here's what I would do: Read the book and whenever you find a statement that even remotely seems "off", do a little research on it (easy in these days of Google). That way, you don't waste the book and you potentially spur yourself to a little extra research.

 

[Permanence]

Indeed the term mass was used. The book tends to make a lot of absolute statements. Okay thank you all for the responses. I'm just going to read through all of it, and then once my textbook arrives I'll probably use that book primarily. Thanks again for all the responses and new insight.

 

[VantagePoint72]

What is the exact quote about the electron not having mass? I'm curious about the context.

 

[256bits]

I would think she is basing the statement on the definition of amu ( depreciated ) of c12 which has 6 neutron, 6 proton and has the definiton of atomic mass of 12, from which all other atomic masses are determined. Rather than go into long detail, about the physics of atomic masses she highly simplified the description, to get on with a discusion of biology.

 

[Ophiolite]

Don't rule out the possibility of poor editing and proof reading. Might the author originally have written "has no significant mass" with the significant later being dropped accidentally?

 

[SW VandeCarr]

Don't rule out the possibility of poor editing and proof reading. Might the author originally have written "has no significant mass" with the significant later being dropped accidentally?

That's certainly possible. However, authors usually have the responsibility for giving final approval to publish.

 

[Ophiolite]

True, but my own extensive experience of proof reading is that writers typically see what they expect to see, not what is actually there. At any rate I certainly agree with all posters who have been surprised by such an elementary error. Equally, of itself it is not a sufficient reason to reject the entire publication - just a warning to be on guard on anything one reads in print. Printing conveys a false sense of authority on the written word.

 

[phinds]

True, but my own extensive experience of proof reading is that writers typically see what they expect to see, not what is actually there. At any rate I certainly agree with all posters who have been surprised by such an elementary error. Equally, of itself it is not a sufficient reason to reject the entire publication - just a warning to be on guard on anything one reads in print. Printing conveys a false sense of authority on the written word.

Well said.

 

[Permanence]

Here is the direct quote:
" Clouds of electrons surround the nucleus. Electrons carry a negative charge but have no mass."

Yeah I thought maybe it was to simplify the issue, but that would be such a poor decision IMO. Thank you all for the responses. Yeah I'm just going to keep reading regardless.

 

[ChrisJA]

..
A. In her discussion of an atom she claimed that an electron does not have any mass. ...
B. The author claimed that DNA is found in every single cell...

This is one method of teaching. Get the answers "close enough" to correct and then come back later and explain the exceptions. The idea is not to over load the student with so many "except or this one exception..." type statements. Teach the big ideas first, then later say "we left this out." It has to do with a students limited short term memory, if you over load it you are ineffective.

Not saying I agree. I don't. It is likely not good to do that at the university level. But think about how you would teach the average ("average", not the smarter) 11 or 12 year old in middle school. The dummies book are written to that level.

 

[mazinse]

this is way way way intro bio here, just go with it for now

 

[ChrisJA]

this is way way way intro bio here, just go with it for now

You just said in one line, what took me seven. You win.

 

[DiracPool]

This is one method of teaching. Get the answers "close enough" to correct and then come back later and explain the exceptions. The idea is not to over load the student with so many "except or this one exception..." type statements. Teach the big ideas first, then later say "we left this out." It has to do with a students limited short term memory, if you over load it you are ineffective.

Yeah, but the mass thing is inexcusable because it does not even serve to simply the argument. Instead of saying:

"Clouds of electrons surround the nucleus. Electrons carry a negative charge but have no mass."

She could have just as easily said, "" Clouds of electrons surround the nucleus. Electrons carry a negative charge and have such a tiny mass that they're almost massless." Or "effectively massless," etc. I think that would have gotten the point across and not been a factual mis-statement. The "all the cells have DNA" issue, on the other hand, I am more comfortable with, because that is one where the petty exception of the RBC's is effectively inconsequential compared to the important general concept that all cells share the same DNA.

But think about how you would teach the average ("average", not the smarter) 11 or 12 year old in middle school. The dummies book are written to that level.

Have you ever read the "quantum mechanics for Dummies" book? Try giving that one to an 11 year old and see if they get past the acknowledgments...:tongue:

 

[Permanence]

I was just about to bring up the QM for dummies LOL. Uh I just don't know why the author would list the mass for the proton and neutron, but not the electron?

Though you are right, this book is far too elementary. I'm really waiting for my textbook to arrive!