Go Back   Freethought Forum > The Library > Articles & Essays > Science

Comment
 
Article Tools Display Modes
An Introduction to Zoology:  Chapter 6
An Introduction to Zoology: Chapter 6
Published by The Lone Ranger
08-07-2008
Default Introduction

An Introduction to Zoology

Chapter Six: Animal Development:



Theories Regarding Animal Development:
Historically, there have been two theories regarding how animals develop. The older theory is referred to as preformation. This theory has been disproved, and it has been shown that animals develop through whatís known as epigenesis. Even so, since itís of historical interest, letís consider the notion of preformation.


Contents

Article Tools

<< <    Next Page: Preformation (Page 1 of 24)    >  >>
  #1  
By monruw on 03-30-2011, 12:55 PM
Default Re: An Introduction to Zoology: Chapter 6

why it's called animal-vegetal axis? sound like kinda food, meat and vegetable or what else~ any story behind this?
Reply With Quote
  #2  
By The Lone Ranger on 05-22-2011, 12:35 AM
Default Re: An Introduction to Zoology: Chapter 6

"Vegetal," is related to "vegetable." Many plants can reproduce asexually, whereas virtually all animals reproduce sexually.

Probably for this reason, "vegetal" came to refer to processes in living things that are "plant-like," especially processes that do not occur through sexual reproduction. More to the point, perhaps, plants generally grow much more slowly than do animals. So the "vegetal" pole of an egg gets its name for the fact that the cells in this region grow and divide much more slowly than do the cells in the "animal" pole.


Cheers,

Michael
Reply With Quote
Comment

  Freethought Forum > The Library > Articles & Essays > Science


Currently Active Users Viewing This Article: 1 (0 members and 1 guests)
 
Article Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 

All times are GMT +1. The time now is 01:14 AM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

Article powered by GARS 2.1.8m ©2005-2006
Page generated in 0.19603 seconds with 17 queries