Comparison of reproductive modes of plants: - PowerPoint PPT Presentation

1 / 7
About This Presentation
Title:

Comparison of reproductive modes of plants:

Description:

Sperm in pollen travels to egg through pollen tube, ... Dicotyledonae (dicots such as trees, roses, daisy) Major characteristics of the two classes: ... – PowerPoint PPT presentation

Number of Views:69
Avg rating:3.0/5.0
Slides: 8
Provided by: Peter6
Category:

less

Transcript and Presenter's Notes

Title: Comparison of reproductive modes of plants:


1
Plant reproductive modes
  • Comparison of reproductive modes of plants
  • Seed plants
  • Heterosporous (different types of spores)
  • Sporophyte dominant gametophyte reduced and
    dependent
  • Reproduction less dependent on water
  • Sperm in pollen travels to egg through pollen
    tube, eliminating need for external water during
    fertilization
  • Evolution of seed, an embryo protected by extra
    layer of sporophyte tissue (seed coat)
  • Protects embryo from desiccation
  • Dormant part of life cycle able to survive until
    favorable conditions appear
  • Enhances dispersal

How are new organisms produced?
2
Plant reproductive modes
  • Comparison of reproductive modes of plants
  • Gymnosperms (e.g. Phylum Coniferophyta)
  • Ovule (structure holding egg) not completely
    enclosed in sporophyte tissue at time of
    fertilization
  • Sperm travels to egg in wind-blown pollen (no
    water)
  • Embryo enclosed in desiccation-resistant seed coat

How are new organisms produced?
3
Plant reproductive modes
  • Comparison of reproductive modes of plants
  • Gymnosperms life cycle

How are new organisms produced?
4
Plant reproductive modes
  • Comparison of reproductive modes of plants
  • Angiosperms (Phylum Anthophyta)
  • Ovule (structure holding egg) completely enclosed
    in sporophyte tissue at time of fertilization
  • Sperm travels to egg in pollen (no need for water)
  • Some pollen is wind dispersed
  • Some pollen is dispersed by insects, birds,
    mammals
  • 3 unique characteristics of angiosperms
  • Flowers (organs holding reproductive structures)
  • Fruit (organs holding seed)
  • Double fertilization (1 sperm 2 polar nuclei
    produce endosperm)
  • Embryo enclosed in desiccation-resistant seed coat

How are new organisms produced?
5
Plant reproductive modes
  • Comparison of reproductive modes of plants
  • Two classes of angiosperms
  • Monocotyledonae (monocots such as grass, lily,
    orchid)
  • Dicotyledonae (dicots such as trees, roses, daisy)
  • Major characteristics of the two classes

Trait monocot dicot
  • Leaf venation parallel network
  • Seed 1 cotyledon 2 cotyledons
  • Flower parts 3s 4s, 5s or many
  • Life cycle few annual most annual
  • Growth in girth none some (trees)
  • Vascular tissue scattered arranged in ring

How are new organisms produced?
6
Plant reproductive modes
  • Comparison of reproductive modes of plants
  • Flower structure
  • Flower parts arranged in whorls (concentric
    rings) on swollen part of stem called receptacle
  • Calyx (sepals that protect flower in bud)
  • Corolla (petals used to attract pollinators)
  • Androecium (male structures)
  • Gynoecium (female structures)

How are new organisms produced?
7
Plant reproductive modes
  • Comparison of reproductive modes of plants
  • Angiosperm life cycle

How are new organisms produced?
Write a Comment
User Comments (0)
About PowerShow.com