1. Ch. 38 Angiosperm Reproduction and Biotechnology
Objectives:
L.O The student can connect concepts in and across domains to show that timing and coordination of specific events are necessary for normal development in an organism and that these events are regulated by multiple mechanisms.
L.O TSIAT use a graph or diagram to analyze situations or solve problems (quantitatively or qualitatively) that involve timing and coordination of events necessary for normal development in an organism.
L.O TSIAT justify scientific claims with scientific evidence to show that timing and coordination of several events are necessary for normal development in an organism and that these events are regulated by multiple mechanisms.
L.O TSIAT describe the role of programmed cell death in development and differentiation, the reuse of molecules, and the maintenance of dynamic homeostasis.
L.O TSIAT design a plan for collecting data to support the scientific claim that the timing and coordination of physiological events involve regulation.
L.O TSIAT justify scientific claims with evidence to show how timing and coordination of physiological events involve regulation.
L.O TSIAT connect concepts that describe mechanisms that regulate the timing and coordination of physiological events.

2. Alteration of generations
38.1 Flowers, Double Fertilization, and Fruits are Unique Features of the Angiosperm Life Cycle
Alteration of generations
Multicellular haploid (n) gametophyte and diploid (2n) generations sporophyte.
Key
Haploid (n)
Diploid (2n)
Gametes
MEIOSIS
FERTILIZATION
Zygote
Mitosis
Diploid multicellular organism
(a) Animals n 2n
Spores
Haploid multi- cellular organism (gametophyte)
Diploid multicellular organism (sporophyte)
(b) Plants and some algae

3. Flower Structure and Function
Flowers are angiosperm’s reproductive organ system.
Flowers’ size, shape, color, odor, organ arrangement, and time of opening are largely influenced by the type of pollinator.
Stamen
Anther
Filament
Petal
Receptacle
Stigma
Style
Ovary
Carpel
Sepal
(a)
Structure of an idealized flower
Simplified angiosperm life cycle
(b)
Key
Haploid (n)
Diploid (2n)
Pollen tube
Germinated pollen grain (n) (male gametophyte)
Ovule
Embryo sac (n) (female gametophyte)
Egg (n)
Sperm (n)
FERTILIZATION
Zygote (2n)
Mature sporophyte plant (2n)
Germinating seed
Seed
Simple fruit
Embryo (2n) (sporophyte)

4. Video: Flower Plant Life Cycle (time lapse)
For the Discovery Video Plant Pollination, go to Animation and Video Files.
Video: Flower Plant Life Cycle (time lapse)
© 2011 Pearson Education, Inc.

5. Pollination Transfer of pollen from an anther to a stigma.
Wind (grasses and trees)
Water (aquatic plants)
Animals; insects, birds, etc.
Abiotic Pollination by Wind
Pollination by Bees
Hazel staminate flowers (stamens only)
Hazel carpellate flower (carpels only)
Common dandelion under normal light
Common dandelion under
ultraviolet light
Pollination by Moths and Butterflies
Blowfly on carrion flower
Pollination by Flies
Pollination by Bats
Moth on yucca flower
Long-nosed bat feeding on cactus flower at night
Hummingbird drinking nectar of columbine flower
Pollination by Birds
Stigma
Anther
Moth
Fly egg

6. Video: Bee Pollinating
© 2011 Pearson Education, Inc.

7. Video: Bat Pollinating Agave Plant
© 2011 Pearson Education, Inc.

8. Coevolution
The evolution of interacting species in response to changes in each other
Many flowering plants have coevolved with specific pollinators
The shapes and sizes of flowers often correspond to the pollen transporting parts of their animal pollinators
Ex: Darwin correctly predicted a moth with a 28 cm long tongue based on the morphology of a particular flower

9. Development of Male Gametophytes in Pollen Grains
Each anther has 4 microsporangia (pollen sacs)
Within this are microsporocytes (2n similar to animal follicle)
These undergo meiosis producing microspores.
These undergo mitosis producing 2 cells (pollen):
Generative: forms 2 sperm
Tube: used to transfer sperm to ovule
Microsporangium (pollen sac)
Microsporocyte
Microspores (4)
Each of 4 microspores
Generative cell (will form 2 sperm)
(LM)
75 m
20 m
MEIOSIS
MITOSIS
Male gametophyte (in pollen grain)
Nucleus of tube cell
Ragweed pollen grain (colorized SEM)
Key to labels
Haploid (n)
Diploid (2n)

10. Development of Female Gametophytes (embryo sac)
Development of a female gametophyte (embryo sac)
100 m
MEIOSIS
MITOSIS
Key to labels
Haploid (n)
Diploid (2n)
(LM)
Embryo sac
Ovule
Megasporangium
Megasporocyte
Integuments
Micropyle
Surviving megaspore
Antipodal cells (3)
Polar nuclei (2)
Egg (1)
Synergids (2)
Female gametophyte (embryo sac)
Occurs within the megasporangium.
The megasporocyte undergoes meiosis making megaspores.
This undergoes mitosis (w/o cytokinesis) making a large cell with 8 nuclei. This is the embryo sac.

11. Double Fertilization
When pollen reaches the stigma, the tube forms, grow down the style to the micropyle (hole in the underside of the embryo sac).
Each sperm has a job:
Fertilizes the egg
Combines with polar bodies making a triploid nucleus in a large cell  endosperm (food storing tissue for seed)
Stigma
Pollen tube 2 3 1
2 sperm
Style
Ovary
Ovule
Micropyle
Pollen grain
Polar nuclei
Egg
Synergid
Endosperm nucleus (3n) (2 polar nuclei plus sperm)
Zygote (2n)

12. Animation: Seed Development
Right-click slide / select “Play”
© 2011 Pearson Education, Inc.

13. Seed Development, Form, and Function
Endosperm develops as a food source (carbohydrates storage)
The embryo divides into a basal cell (anchor) and terminal cell (embryo) and cotyledon forms (another food supply)
Seed dehydrates entering dormancy.
This is an adaptation for when environmental conditions are right for imbibition (uptake of water to start germination)..
Ovule
Endosperm nucleus
Integuments
Zygote
Terminal cell
Basal cell
Proembryo
Suspensor
Cotyledons
Shoot apex
Root apex
Seed coat
Endosperm

14. Fruit Form and Function
Fruit is the ovary of the flower which protects and aids in dispersal of the seed.
Types of fruit:
Stamen
Ovary
Stigma
Ovule
Pea flower
Seed
Pea fruit
(a) Simple fruit: 1 carpel
(b) Aggregate fruit:
many carpels
(c) Multiple fruit:
Many flowers
(d) Accessory fruit: carpel is the core,
The flesh is the receptable.
Carpels
Raspberry flower
Carpel (fruitlet)
Raspberry fruit
Flower
Pineapple inflorescence
Each segment develops from the carpel of one flower
Pineapple fruit
Petal
Style
Sepal
Ovary (in receptacle)
Apple flower
Remains of stamens and styles
Sepals
Receptacle
Apple fruit

15. Seed Dispersal Dispersal by Wind Dispersal by Water Dandelion fruit
Dandelion “seeds” (actually one-seeded fruits)
Winged fruit of a maple
Dandelion fruit
Tumbleweed
Dispersal by Water
Winged seed of the tropical Asian climbing gourd Alsomitra macrocarpa
Coconut seed embryo, endosperm, and endocarp inside buoyant husk

16. Seed Dispersal Dispersal by Animals
Fruit of puncture vine (Tribulus terrestris)
Squirrel hoarding seeds or fruits underground
Ant carrying seed with nutritious “food body” to its nest
Seeds dispersed in black bear feces

17. Animation: Fruit Development Right-click slide / select “Play”
© 2011 Pearson Education, Inc.