Sexual Reproduction in Flowering Plants-1

8/4/2019 Sexual Reproduction in Flowering Plants-1

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Sexual Reproduction InSexual Reproduction In

Flowering PlantsFlowering Plants

ByBy

Matthew SinMatthew Sin

Nicholas JackNicholas JackKhooKhoo

LimLim BoxianBoxian

EdwardEdward KhantKhant

Matthew TanMatthew Tan

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Objectives of this Lesson

The objectives of this lesson are to be able to:The objectives of this lesson are to be able to:

Understand the various methods of asexualUnderstand the various methods of asexualreproduction in flowering plants.reproduction in flowering plants.

Understand the advantages and disadvantages ofUnderstand the advantages and disadvantages ofasexual & sexual reproduction.asexual & sexual reproduction.

State the functions of sepals, petals, anthers andState the functions of sepals, petals, anthers andcarpelscarpels..

Outline the process of pollination:Outline the process of pollination: selfself--pollinationpollination

crosscross--pollinationpollination

Understand the various ways in which fruits & seedsUnderstand the various ways in which fruits & seedsare dispersed.are dispersed.


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Asexual Reproduction In FloweringAsexual Reproduction In Flowering

PlantsPlants

Only one parent is involved in asexualreproduction.

Reproduction without the fusion of gametes.

Creating a plant using techniques such asmarcotting, grafting, budding, using cuttings,layering or division without using seeds can alsobe called asexual reproduction. (artificialvegetative propagation)

Plant offspring will be substantially identical to

the parent.

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Methods of Asexual Reproduction inMethods of Asexual Reproduction inFlowering PlantsFlowering Plants

Method Description Plant Examples

Rhizomes Hor izontal stem of a plant that is usually foundunderground

Cattails

Tubers Modif ied p lant structures that are enlarged to storenutrients and are used by plants over winter andregrow the next year

Irish Potatoes

Runners (Stolons) Horizontal stems which grow at the soil surface orbelow ground forming new plants at the end or thenodes

Strawberry Plant

Plantlets Young or small plan ts used as propagulesand are

usually grown from clippings of mature plants

Duckweed

Bulbs Underground vertical shoot that has modified leaves (orthickened leaf bases) that are used as food storageorgans by a dormant plant.

Onions

Corms A short, vertical, swollen underground plant stemserves as a storage organ used by some plants tosurvive adverse conditions such as summer drought. Itconsists of one or more internodes with at least onegrowing point.

Gladiolus


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Pros & Cons of AsexualPros & Cons of Asexual

Reproduction in PlantsReproduction in Plants

Pros:Pros:1.1. Numerous offspring can beNumerous offspring can be

produced without "costing"produced without "costing"

the parent a great amount ofthe parent a great amount of

energy or timeenergy or time

2.2. There will not be a change inThere will not be a change in

environment so the newenvironment so the new

plant does not have to adaptplant does not have to adapt

to its new climateto its new climate

3.3. Cloned offspring are moreCloned offspring are more

likely to succeed in the samelikely to succeed in the same

stable areas as their parents.stable areas as their parents.

Cons:Cons:1.1. The new plant will growThe new plant will grow

closely to the parent plantclosely to the parent plant

and the other new plantsand the other new plants

causing them to fight forcausing them to fight for

water, nutrients and sunlightwater, nutrients and sunlight

2.2. Less genetic diversity givesLess genetic diversity gives

the offspring lesser chance ofthe offspring lesser chance of

survival if the environmentsurvival if the environment

changeschanges

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Sexual Reproduction in FloweringSexual Reproduction in FloweringPlantsPlants

The formation of a new organism from 2 parentsThe formation of a new organism from 2 parents

Involves the fusion of the joining of gametes to form aInvolves the fusion of the joining of gametes to form a

single cell called the zygote or fertilized eggsingle cell called the zygote or fertilized egg

The offspring are similar, but not identical to the parentThe offspring are similar, but not identical to the parent


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Methods of Sexual Reproduction inMethods of Sexual Reproduction in

Flowering PlantsFlowering Plants

Night-blooming CereusTransfer of the pollens to thestigma of another flower onanother plant of the same kind

Cross-Pollination

PeanutTransfer of pollens to thestigma of the same flower or adifferent flower in the sameplant

Self-Pollination

ExamplesDescriptionMethod

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Pros & Cons of SexualPros & Cons of SexualReproduction in Flowering PlantsReproduction in Flowering Plants

Pros:Pros:

1.1. Greater geneticGreater genetic

variation in offspringvariation in offspring

2.2. Greater chance ofGreater chance of

survival in changingsurvival in changing

environmentsenvironments

Cons:Cons:

1.1. Energy is expanded inEnergy is expanded in

finding a matefinding a mate

2.2. Reproduction is lessReproduction is less

likely because of thelikely because of the

need to have 2 matesneed to have 2 mates

from 2 different gendersfrom 2 different genders


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Reproductive Parts in a Plant

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Pollen Grain Under the Microscope


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Pollen Grain In Detail

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Functions of Plant ReproductiveFunctions of Plant ReproductivePartsParts

Reproductive Parts Functions

Sepals Provides protection for the delicate internalstructures and a small amount of food throughphotosynthesis for the remainder of the floralparts

Petals Designed for protection and their arrangement isoften an attractant to the various animals such asinsects that are necessary for the transfer ofgametes or pollination

Anthers It is the site of the production of pollen grainswhich is the male gamate

Carpels It is the most central structure within the flowerand actually is a leaf which has been modified toproduce ovules


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SelfSelf--PollinationPollination

The transfer of pollen from the anther of a flower toThe transfer of pollen from the anther of a flower to

the stigma of the same flower or sometimes to thatthe stigma of the same flower or sometimes to that

of a genetically identical flower.of a genetically identical flower.

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Process of SelfProcess of Self--PollinationPollination

11.Petals, also known as corolla, wilts.Petals, also known as corolla, wilts

22.The upper lip of the petal/corolla, known as the.The upper lip of the petal/corolla, known as the galaegalae, brings the pollen, brings the pollen--filledfilled

anthers towards the stigmaanthers towards the stigma

33.Once the two touch, pollination occurs.Once the two touch, pollination occurs


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CrossCross--PollinationPollination

The transfer of pollen from the anther of one flowerThe transfer of pollen from the anther of one flower

to the stigma of another with a different geneticto the stigma of another with a different genetic

composition, as by insects, or deliberately by acomposition, as by insects, or deliberately by a

botanist.botanist.

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Process of CrossProcess of Cross--PollinationPollination

Cross Pollination involves two flowers and their respectiveCross Pollination involves two flowers and their respectivemale and female parts ( stamen and the stigma) of the twomale and female parts ( stamen and the stigma) of the twoflowersflowers

From the flower, the pollinator (e.g. A bee) uses a methodFrom the flower, the pollinator (e.g. A bee) uses a methodcalledcalledsonicationsonicationororbuzz pollinationbuzz pollination to release the pollen.to release the pollen.

They do this by grabbing a flower and vibrating rapidlyThey do this by grabbing a flower and vibrating rapidlythrough their movement of flight, which soon causes thethrough their movement of flight, which soon causes thepollen to dislodge and then stick to the pollinator , who thenpollen to dislodge and then stick to the pollinator , who thendrops them in another plant which has female partsdrops them in another plant which has female parts

It is at this instance that crossIt is at this instance that cross--pollination occurspollination occurs

(Besides bees, pollination can also occur through wind ((Besides bees, pollination can also occur through wind (anemophily) or water (anemophily) or water (hydrophilyhydrophily) but the plants which uses) but the plants which usesthese methods have specialthese methods have special adaptionsadaptions..


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Dispersion of Fruits and Seeds

It refers to the species movement away from an existingpopulation or away from the parent organism

Plants disperse their seeds to ensure that thecompetition of nutrients, sunlight and water is asminimal as possible

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Ways in Which Fruits and Seeds AreDispersed

Wind

Animals (eaten then passed out OR hook onto theanimals outer coat)

Splitting

Moving Water


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Did you know? Insects, such as the bee aid the plant in the procDid you know? Insects, such as the bee aid the plant in the processess

of crossof cross--pollination? Out of all the insects , the bee in particular,pollination? Out of all the insects , the bee in particular,

works the hardest ,spending hours on end of moving from flower tworks the hardest ,spending hours on end of moving from flower too

flower. So the next time you see a bee, reflower. So the next time you see a bee, re--consider before trying toconsider before trying to

end its small yet significant life.end its small yet significant life.

Without our little insect friends, we may not evenWithout our little insect friends, we may not even

be able to reap the benefits of fruits ! So rememberbe able to reap the benefits of fruits ! So remember

we owe them that much!we owe them that much!

Fun Facts

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ConclusionsConclusions

In the world, there are many pros and cons to things,In the world, there are many pros and cons to things,

such as asexual and sexual reproduction in plants.such as asexual and sexual reproduction in plants.

There is noThere is noperfectperfectway to reproduce, but there areway to reproduce, but there are

various ways to. With this, we can all look out and seevarious ways to. With this, we can all look out and see

the beauty of the life, and appreciate what we have inthe beauty of the life, and appreciate what we have in

the world today, from the trees that grace the earth tothe world today, from the trees that grace the earth to

thethe litthlelitthle insects that help pollinate the plants to give usinsects that help pollinate the plants to give usfruits.fruits.


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CREDITSCREDITS

http://www.germeshttp://www.germes --online.com/catalog/2/134/86592/sell_raw_peanuts_in_shell.htmlonline.com/catalog/2/134/86592/sell_raw_peanuts_in_shell.html

http://www.germeshttp://www.germes --online.com/catalog/2/161/158660/sell_green_soybeans.htmlonline.com/catalog/2/161/158660/sell_green_soybeans.html

http://www.biology.iastate.edu/intop/1Australia/Australia%20papehttp://www.biology.iastate.edu/intop/1Australia/Australia%20pape rs/Discoveries%20aboutrs/Discoveries%20about%20Marsupial%20Rep%20Marsupial%20Rep

http://proxy.arts.uci.edu/~nideffer/Hawking/early_proto/orgel.hthttp://proxy.arts.uci.edu/~nideffer/Hawking/early_proto/orgel.ht mlml

https://reader009.{domain}/reader009/html5/0513/5af85587393c5/5af8558fb74d8.jpghttps://reader009.{domain}/reader009/html5/0513/5af85587393c5/5af8558fb74d8.jpg http://www.quizilla.com/user/MiniSorceressEvil26/friends/http://www.quizilla.com/user/MiniSorceressEvil26/friends/

http://http://wikipedia.orgwikipedia.org//

Sexual Reproduction in Flowering Plants-1

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