1128 - November 28, 2011 Lecture 7 1. from what structures...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
November 28, 2011 Lecture 7 1. from what structures did carpels evolve? a) Carpels may have evolved from leaves with sporangia along their margins, which folded inwards b) over evolutionary time, carpels became progressively more fused and buried in the receptacle, forming the ovary and protecting the megasporangia inside of ovules c) the ovary also protects the developing seeds 2. gymnosperms: megasporophylls arranged in a megastrobilis = cone 3. angiosperms: enclosed within several thick layers of tissue which are attractive to animals for dispersal 4. evolution of the carpel from the megastrobilis a) similar to gymnosperm megasporophyll, a carpel is a leaf-like structure that bears one or more ovules on its upper surface b) unlike a gymnosperm megasporophyll, the carpel is folded over along its “midrib” and encloses the seed(s) c) unlike a gymnosperm megasporophyll, angiosperm pollen must produce a tube that penetrates a stigma and style 5. stamens evolved from leaf-like structures
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/07/2011 for the course EEMB 3 taught by Professor Carlson during the Fall '08 term at UCSB.

Page1 / 2

1128 - November 28, 2011 Lecture 7 1. from what structures...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online