PA Chapter 21 - Chapter 21: Flowers: Reproductive Cycle 1...

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

View Full Document Right Arrow Icon
Chapter 21: Flowers: Reproductive Cycle 1 Sporangium type 1 spore type Homospory 2 Sporangia types 2 spore types Heterospory Megaspores (female) or Microspores (male). Microsporogenesis Mircrosporogenesis refers to the formation of microspores by the process of meiosis. This takes place in the microsporangium of the anther. The microspores then rapidly continue development, become multicellular, and produce the microgametophyte , otherwise known as the pollen grain. In the anther, the wall develops epidermis, endothecium (helps to open) and tapetum (inner lining of the pollen sac) layers as the inner sporogenous tissue enlarges and becomes microsporocytes or microspore mother cells. The microgametophyte: Pollen The mature microgametophyte mis multicellular (2 or 3 cells), and has a thick, resistant wall composed of sporopollenin. The wall is composed of an outer portion or exine and an inner portion, the intine. Thinner areas in the wall are apertures that allow for germination;
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 04/15/2010 for the course BOT 4223 taught by Professor Harris during the Fall '09 term at University of Central Florida.

Page1 / 2

PA Chapter 21 - Chapter 21: Flowers: Reproductive Cycle 1...

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