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Chapter 6 Overview. Fruit s & Flowers. Chapter 6 Overview. http://www.ddflowers.com.sg/Products/Thumbnail/192-GW016-LO.JPG. What are fruits & flowers for?. When you bite into a juicy peach or when you give someone a bouquet of daisies or roses- you probably aren’t thinking:
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Chapter 6 Overview Fruits & Flowers Chapter 6 Overview http://www.ddflowers.com.sg/Products/Thumbnail/192-GW016-LO.JPG
What are fruits & flowers for? • When you bite into a juicy peach or when you give someone a bouquet of daisies or roses- you probably aren’t thinking: “ Wow, these are marvelous structures designed to facilitate effective sexual selection & maximize reproductive success in angiosperm plants!” • From now on- this is what you should be pondering!
Plant reproduction is complex • Unlike humans, who reproduce only sexually, with a single method, plants have a variety of ways of reproducing. • Asexual • Sexual
Asexual Reproduction: • Also known as ‘ vegetative propagation” • Offspring are clones of parent • Genetically identical • Cell division by mitosis
Review: Stages of Mitosis Divided into 4 phases: 1. PROPHASE 2. METAPHASE 3. ANAPHASE TELOPHASE Memory aid: Pro met Anna on the telophone
http://jabberwiki.wikispaces.com/file/view/mitosis1.gif/53565174http://jabberwiki.wikispaces.com/file/view/mitosis1.gif/53565174
Can you find a cell in each phase of mitosis? http://www.bioweb.uncc.edu/1110Lab/notes/notes1/labpics/Onion%20Prophase%20and%20%20Metaphase%2020x.jpg
Example of Plant asexual reproduction: 1. Strawberry plants- sends out stolons or runners • Only need a few plants to start a strawberry bed. http://www.smallkitchengarden.net/wp-content/uploads/c37d59f25bed5e2.jpg
Examples of Plant asexual reproduction: 2. Kalanchoe diagremontiana “walking fern” plant • Produces “plantlets” on the edges of leaves- a leaf that touches the ground grows into a new plant http://pics.davesgarden.com/pics/WUVIE_1189126100_673.jpg
Example of Plant asexual reproduction: 3. Quaking aspen trees • Adventitious roots make a large group of trees • The whole group is called a “clone” http://www.coloradotreefarmnursery.com/photogallery/Deciduous%20Trees/Aspen/Aspen%201/Aspen.jpg
Sexual reproduction in plants • Sexual reproduction uses process of Meiosis • Gametes- are Haploid cells • Spores, Sperm (pollen), eggs (ovule) • Form a Zygote – the fertilized egg • Genetic recombination of genes produces a unique individual.
Review: Sexual Reproduction in plants has “Alternation of generations” • life cycle with 2 different generations. • a Haploid Gametophyte produces gametes. • Gametes unite and give rise to a Diploid Sporophyte, which produces spores or haploid cells
REVIEW: In flowering seed plants - angiosperms: • 2 fertilization events take place: • one sperm fertilizes the egg to form the diploid zygote of the new individual, • the other sperm fertilizes the polar nuclei to form the triploid endosperm, a nutritive tissue (the FRUIT). • Together with maternal sporophyte tissue, these make up the seed.
Flowers, fruit & seeds • Only in angiosperm plants • With nearly 250,000 species- there is great variety in flower structure • All flowers sit at the top of the stem part called the peduncle http://content.answers.com/main/content/img/Gardeners/f0186.jpg
Inflorescence • A peduncle bearing a group of flowers • Several different types shown below: http://www3.hcs.ohio-state.edu/wiki/images/d/d2/Inflor.GIF
Flowers • highly specialized reproductive organs, • reproductive functions include: • Advertising (attracting pollinators) • pollination • fertilization • seed development • Seeds dispersal
Parts of a flower Male parts: -stamen Female parts: -Carpel, also called pistil 2 other modified leaves: -Sepals -Petals http://andromeda.cavehill.uwi.edu/Plant%20Propagation%20Practical%20Photos/Generalised_Flower_Diagram.jpg
Complete & Incomplete Flowers • Compete flower- if it contains all four types of modified leaves : • Sepals • Petals • Stamens • Carpels • Incomplete Flowers- lack one or more of these modified leaves
Perfect flowers • Perfect- also known asbisexual flowershave both male (stamens) & carpels (pistil) parts on same flower. • Roses • Olives (also has staminate flowers) • Apples • Cherries • Nectarines
Imperfect- unisex flower • Has either stamen or carpel (pistil) –not both • Has only one set of reproductive organs • Two types of imperfect flowers (either male or female) • Staminate flowers contain only stamens, the male reproductive part of the flower. • Pistillate flowers only contain the pistil, or female, reproductive
Flowers have ovaries in different positions: • The location of the ovary to the sepals & petals: *Superior *Semi-Inferior *Inferior
Types of plants: • Monoecious plants have male and female parts on the same plant • (corn, cucurbits, birch, walnut). • Dioecious plants have male and female flowers on separate plants • (hemp, American holly, hazel nut).
Apples have perfect flowers • Green sepals (6) protect the bud before the flower opens. • Petals (1) white, -are highly visible to the insect pollinators. • Male parts -filament (5) and anther (4). Pollen is produced in its anthers • Female parts: stigma (2), style & ovary (7)). • Pollen land on the stigma, forms a pollen tube that grows down the style (3) to the ovary (7), where it releases the male gamete & fertilizes the ovule in the ovary. • The fertilized ovule develops into a seed and the ovary typically develops into the fruit. quorumsensing.ifas.ufl.edu/HCS200/Breefrme.html
Blackberries have perfect flowers www.cobaltinc.com/.../Classify/classifi.htm
How to Identify Male and Female Zucchini Flowers Female Flower Male Flower
Imperfect flowers: Hazelnut- separate male & female flowers on same plant
Grasses -monocots • flowers of grasses are less showy (“fescue flower”). • produce significant amounts of pollen in their anthers (4). • Carried by wind, pollen lands on sticky feather-like stigma receptacles (2). • Sepals and petals of grasses have evolved into three layers of protective bracts -glume, palea, and lemma (9). quorumsensing.ifas.ufl.edu/HCS200/Breefrme.html
Fruit: • is a ripened (mature) ovary • Where seeds develop & are found • serves as protection • Means of dispersal for the seeds http://biology.clc.uc.edu/courses/bio106/angio.htm
Some types of fruits: -Simple fruits -from one ovary in one flower. Examples: walnut, tomato, orange, cherry, apple, dandelion, and maple “helicopter.” -Different types of simple fruit- each has its own official name. Aggregate fruits arise from several ovaries in one flower. Examples include raspberry and strawberry. Multiple fruits arise from ovaries in several, tightly-clustered flowers which grow together into one “fruit.” Examples include pineapple, mulberry, and breadfruit. http://biology.clc.uc.edu/courses/bio106/angio.htm
Some activities: • Fruits game • Dissect flower
Your assignment: • Read Ch 6 • Section review questions Page 130, # 1 & 3 Page 134 # 1- 3 Page 143 # 1- 3 • Read pages 137 & 138 - boxes about Apomixis, & Tropical Fruits • Page 144, Thought question: #1