Presentation is loading. Please wait.

Presentation is loading. Please wait.

Ch. 38 Angiosperm Reproduction and Biotechnology Objectives: L.O. 2.31 The student can connect concepts in and across domains to show that timing and coordination.

Similar presentations


Presentation on theme: "Ch. 38 Angiosperm Reproduction and Biotechnology Objectives: L.O. 2.31 The student can connect concepts in and across domains to show that timing and coordination."— Presentation transcript:

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 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 MEIOSISFERTILIZATION Zygote Mitosis Diploid multicellular organism (a) Animals n n n 2n2n 2n2n 2n2n 2n2n n n n n n MEIOSISFERTILIZATION Mitosis Gametes Spores Zygote 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) Anther Pollen tube Germinated pollen grain (n) (male gametophyte) Ovary 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 © 2011 Pearson Education, Inc. Video: Flower Plant Life Cycle (time lapse)

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 © 2011 Pearson Education, Inc. Video: Bee Pollinating

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

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) 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. (b) 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) Ovule Integuments Female gametophyte (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: 1.Fertilizes the egg 2.Combines with polar bodies making a triploid nucleus in a large cell  endosperm (food storing tissue for seed) Stigma Pollen tube sperm Style Ovary Ovule Micropyle Pollen grain Polar nuclei Egg Ovule Polar nuclei Egg Synergid 2 sperm Endosperm nucleus (3n) (2 polar nuclei plus sperm) Zygote (2n)

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

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 Basal cell Cotyledons Shoot apex Root apex Suspensor 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 Stamen Raspberry flower Carpel (fruitlet) Stigma Ovary Stamen Raspberry fruit Flower Pineapple inflorescence Each segment develops from the carpel of one flower Pineapple fruit Stigma Petal Style Stamen Sepal Ovule Ovary (in receptacle) Apple flower Remains of stamens and styles Sepals Seed Receptacle Apple fruit

15 Seed Dispersal Dispersal by Wind 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 © 2011 Pearson Education, Inc. Animation: Fruit Development Right-click slide / select “Play”


Download ppt "Ch. 38 Angiosperm Reproduction and Biotechnology Objectives: L.O. 2.31 The student can connect concepts in and across domains to show that timing and coordination."

Similar presentations


Ads by Google