Biotechnology
Chapter 38: Angiosperm Reproduction and Biotechnology
I. Overview: Flowers of Deceit 1. Angiosperm flowers can attract pollinators using visual cues and volatile chemicals 2. Many angiosperms reproduce sexually and asexually 3. Symbiotic relationships are common between plants and other species
II. Concept 38.1: Flowers, double fertilization, and fruits are unique features of the angiosperm life cycle 1. Diploid (2n) sporophytes produce spores by meiosis; these grow into haploid (n) gametophytes 2. Gametophytes produce haploid (n) gametes by mitosis; fertilization of gametes produces a sporophyte 3. Angiosperms- sporophyte is dominant generation, the large plant * gametophytes are reduced in size and depend on the sporophyte for nutrients 4. Angiosperm life cycle- the “three Fs”: flowers, double fertilization, and fruits
A. Flower Structure and Function 1. Flowers -reproductive shoots of the angiosperm sporophyte; they attach to a part of the stem called a. receptacle- where flower attaches to the stem b. Flowers has four floral organs: sepals, petals, stamens, and carpels c. Stamen consists of a filament topped by an anther with pollen sacs that produce pollen d. Carpel has a long style with a stigma on which pollen may land e. Ovary at the base of the style, containing one or more ovules f. Pistil- single carpel or group of fused carpels
Stamen
Anther
Filament
Stigma
Carpel
Style
Ovary
Receptacle
Sepal
Petal
(a) Structure of an idealized flower
Fig. 38-5a
Stigma
Pollen tube
2 sperm
Style
Ovary
Ovule
Micropyle
Egg
Pollen grain
Polar nuclei
Structure of the Carpel 2. Types of flowers a. Complete flowers contain all four floral organs b. Incomplete flowers lack one or more floral organs c. Inflorescences-
I. Overview: Flowers of Deceit 1. Angiosperm flowers can attract pollinators using visual cues and volatile chemicals 2. Many angiosperms reproduce sexually and asexually 3. Symbiotic relationships are common between plants and other species
II. Concept 38.1: Flowers, double fertilization, and fruits are unique features of the angiosperm life cycle 1. Diploid (2n) sporophytes produce spores by meiosis; these grow into haploid (n) gametophytes 2. Gametophytes produce haploid (n) gametes by mitosis; fertilization of gametes produces a sporophyte 3. Angiosperms- sporophyte is dominant generation, the large plant * gametophytes are reduced in size and depend on the sporophyte for nutrients 4. Angiosperm life cycle- the “three Fs”: flowers, double fertilization, and fruits
A. Flower Structure and Function 1. Flowers -reproductive shoots of the angiosperm sporophyte; they attach to a part of the stem called a. receptacle- where flower attaches to the stem b. Flowers has four floral organs: sepals, petals, stamens, and carpels c. Stamen consists of a filament topped by an anther with pollen sacs that produce pollen d. Carpel has a long style with a stigma on which pollen may land e. Ovary at the base of the style, containing one or more ovules f. Pistil- single carpel or group of fused carpels
Stamen
Anther
Filament
Stigma
Carpel
Style
Ovary
Receptacle
Sepal
Petal
(a) Structure of an idealized flower
Fig. 38-5a
Stigma
Pollen tube
2 sperm
Style
Ovary
Ovule
Micropyle
Egg
Pollen grain
Polar nuclei
Structure of the Carpel 2. Types of flowers a. Complete flowers contain all four floral organs b. Incomplete flowers lack one or more floral organs c. Inflorescences-