Question

How do cells know how to develop within a multicellular organism

a.They all develop in exactly the same way.

b.They receive instructions in their DNA

c.They follow a pattern that comes from outside the cell.

d.They learn as they go along.
wich is right?

Answer 1

Use process of elimination. Rather than try to figure out which one it is, work through the problem. Do any of the options strike you as unlikely?

Answer 2

B. This is known as differential switching on of genes

Answer 3

thanks

Answer 4

I got 100% thank you guys so much

Answer 5

Actually, I would dispute that answer. If you look at the case where we all start, with 8 identical cells, the initial cues which send those eight cells down different developmental paths are maternally derived. And some of it has to do with fluke random chance - which RNA transcripts and proteins end up in which cells as they divide.

Answer 6

One case where the 'standard textbook answer' is entirely wrong, biologically.

Answer 7

um ok :/

Answer 8

@blues after the eight celled stage the internal DNA also directs the development.....

Answer 9

Shruti, I am well aware of that. Thanks. Which is why I very deliberately limited the discussion to the 8 cell stage as opposed to anything later.

The scientific point is that those initial cues which direct all further development are in large part maternally derived, and in lesser part due to random physical, spatial location of low copy transcripts in dividing cells.

And the pedagogic point is that 'standard textbook answer' are, scientifically speaking, extremely blunt and obtuse. To the point of marking frankly wrong statements 'right' when teaching people.

Answer 10

@blues Multiple choice is sometimes choosing the answer that's right most of the time, although there are exceptions to that.

Answer 11

Of course. The point is that this is a lousy question.

Of course, on OpenStudy, 'multiple choice' means guiding the user to the answer that is most likely correct rather than just giving it to them. That way the person gets something more out of it - in this case an understanding as per why the question is incorrect - rather than just a perfect score on their graded work.

Answer 12

i totally agree wid u blues...but this is a exception....what @Kira_Yamato replied was for the normal condition...

Answer 13

In fact I agree with you too @blues and @shrutipande9, sadly this question is set this way....

Answer 14

The scientific point is that these 'normal conditions' are established by signals from the mother and by random chance. Without those signals at the very start of development, there would be no 'normal conditions.' It is a lousy, lousy question with an answer that is by no means clear. Or scientifically accurate.

Answer 15

i know i guess we all should just stop discussing...because we all are right...:P

Answer 16

me too i got a 100% too

Answer 17

@shareefzubair @queenpup920
k12?