BCB311

Thursday, March 16, 2006

ANGIOSPERMS-FLOWERING PLANTS HAVE ARRIVED

Angiosperms are floweing plants that bear reproductive organs:androecium (male) and/or gynoecium (female) in the flower structure;they also cover their seeds in a true fruit (http://en.wikipedia.org/wiki/Angiosperms#History)  .More primitive angiosperms would be monoecios ie. their male and female organs are situated on separate flowers , whereas modern angiosperms are dioecious ie. their male and female organs are situated on one perfect flower, this is also known as being hermaphrodite (http://en.wikipedia.org/wiki/Angiosperms#History) .Angiosperms constitute the dominant land vegetation of the Earth's surface (http://en.wikipedia.org/wiki/Angiosperms#History) .
 
During the Cretaceous era (145-65 million years ago) saw the rise of flowering plants and their associated insect pollinators by the process of co-evolution (http://www.geocites.com/we_evolve/Plants/angiosperm.html) Although the first fossil evidence of angiosperms appeared in the fossil record approximately 140 million years ago (Jurassic era). This co-evolution between plants and insects was most probably the most influential driving force behind the origin and diversification of angiosperms, although it has been disputed that seed production, dispersal and seedling establishment was the most important angiosperm origin (http://www.geocites.com/we_evolve/Plants/angiosperm.html) .By the late Cretaceous angiosperms became the most dominant group of land plants (http://en.wikipedia.org/wiki/Angiosperms#History) .
 
The success of angiosperms can be attributed to the mutualistic relationship with pollinators, as angiosperms have counter adapted to prevent pollinators from consuming pollen and seeds (http://www.as.wvu.edu ) , counter adaptations include the production of nectar and seeds inclosed in a fruit as pollinators consume the fruit that surrounds the seeds ,therefore sparing pollen and seeds and playing a major role in pollen and seed dispersal (http://www.as.wvu.edu ) .
 
 

 
 
Simone Neethling
BCB Department
University of the Western Cape
241343632@uwc.ac.za

1 Comments:

  • Great - what I was wanting! BUT your punctuation sucks - fullstops end a sentence. Np spaces before a comma, etc etc. As a scientist attention to detail is important.

    By Anonymous Rich, at Friday, March 17, 2006 7:35:00 pm  

Post a Comment

Links to this post:

Create a Link

<< Home