![Page 1: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/1.jpg)
Angiosperm Reproduction
http://www.physicalgeography.net/fundamentals/images/angiosperm2.jpg
![Page 2: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/2.jpg)
Seed Double Fertilization
The union of two sperm cells with different nuclei of the embryo sac. Makes the embryo and the endosperm
Endosperm Food storing tissue
of the seed.
http://www.learner.org/channel/courses/essential/life/images/show4.open_seed.jpg
![Page 3: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/3.jpg)
Seed http://students.usm.maine.edu/deidre.rice/seed.JPG
![Page 4: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/4.jpg)
Seeds and Eggs Seeds are plant products
which encloses the embryo with a hard coat and food supplies.
Eggs are animal products which enclose an animal embryo with a hard or leathery shell and food supply.
Eggs are similar to seeds because they protect the embryo while allowing gas exchange
![Page 5: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/5.jpg)
From Ovule to Seed After Double Fertilization, each ovule develops into
a seed.
These seeds carry enough food and supplies until germination period.
Seeds sinks down because the Endosperm is filled with the heavy supplies.
Cotyledons swell to show that the Endosperm is filled with nourishment.
![Page 6: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/6.jpg)
Endosperm An example of liquid Endosperm are the
coconut milk.
An example of solid Endosperm is the coconut meat itself. Also the white puff inside the popcorn is also the endosperm.
Seeds carry endosperms until they are mature enough
![Page 7: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/7.jpg)
Endosperm Development http://www.niles-hs.k12.il.us/amilef/APReviewOut/SwatiCh38/SwatiChapter38_files/image008.jpg
![Page 8: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/8.jpg)
Development of Plant Embryo http://www.nicertutor.com/doc/class/bio1152/Locked/media/ch38/38_07EudicotEmbryogenesis.jpg
![Page 9: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/9.jpg)
Structure of a Mature Seed Dehydrated and enclosed with a seed
coat.
Hypocotyl Where cotyledons are attached
Epicotyl Consists of the shoot tip and a pair of mini
leaves.
![Page 10: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/10.jpg)
Seed Structure http://www.starkliteraria.com/dicotseed.gif
![Page 11: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/11.jpg)
Fruits Fruits protects the seed by aiding in dispersal by
wind or animals.
Fruits are products of matured flowers.
If the flower is not pollinated, then it just withers and falls of the tree.
Fruits usually dries up as the seed inside matures. Its because of the enzymes digesting the cell walls of the fruits, in other words, the mature the fruit is, the sweeter it is because of many starch are converted to sugar.
![Page 12: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/12.jpg)
Kinds Of Fruit
Simple Fruit
http://65.214.37.88/ts?t=1274929236378461867
Aggregate Fruits
http://www.tarleton.edu/~range/Sanderson/02066%20aggregate%20fruit%20blackbery.jpg
![Page 13: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/13.jpg)
Seed Germination When seeds mature, they dehydrate and
went into a coma state called dormancy.
Being dormant means that the cell has low metabolic state.
Until the environment provides a suitable condition, the seed will remain dormant.
Dormancy is an evolutionary step because it promotes seed life by making it go to sleep and wakes up when the time is right.
![Page 14: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/14.jpg)
Seed to Seedling Imbibition is that state when the seed wakes up
from dormancy and starts the intake of water.
It causes the seed to expand and ruptures, releasing the shoot, the cotyledons and the stalk.
It is the first sign of life after the dormant state.
![Page 15: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/15.jpg)
Seed to Seedling http://students.usm.maine.edu/deidre.rice/_ILLUS_ILT_T630888A.GIF
![Page 16: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/16.jpg)
Asexual Reproduction: plant cloning
• Asexual reproductions results in exact clones of the parent, where sexual reproduction generates the genetic variation that contributes to evolutionary adaption.
• Some plants still use meiosis during the process of asexual reproduction, and some just perform mitosis.
• Also known as vegetative reproduction.
![Page 17: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/17.jpg)
Mechanisms of Asexual Reproduction
• Plants have meristematic tissues of dividing, indifferentiated cells.
• These cells can sustain or renew growth indefinitely.
• Parenchyma cells throughout the plant can divide and differentiate into more specialized types of cells (regeneration of lost parts)
• Fragmentation is the separation of a parent plant into parts that develop into whole plants.
• Apomixis is the asexual reproduction of a seed. (different from fragmentation.)
• A diploid cell in the ovule gives rise to the embryo, the ovule matures into seeds, and are either dispersed or grow on the spot.
![Page 18: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/18.jpg)
Hereditary testing of apomixis http://www.uaf.edu/grnhouse/images/gary.jpg
![Page 19: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/19.jpg)
Vegetative Propagation and Agriculture
• Asexual reproduction has been harnessed by farmers to enhance harvests.
• Many gardeners use cuttings, or fragments of plants, to produce clones. These fragments usually come from the shoot or stem of the plant.
• A callus forms at the open end of the fragment, followed by the growth of roots. If the fragment includes a node, then it skips the callus stage.
![Page 20: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/20.jpg)
Grafting
• Grafting makes it possible to combine the best qualities of different species or varieties into a single plant.
• A twig or bud from one plant is grafted onto a plant of a closely related species or a different variety of the same species.
• Usually done in young plants.
• Plant receiving part is the stock, twig grafted onto the stock is the scion.
![Page 21: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/21.jpg)
http://agspsrv34.agric.wa.gov.au/agency/images/4332046.jpg
This plant was grown from a tissue culture.
![Page 22: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/22.jpg)
Artificial Selection • Natural Hybridization of plants is common in nature and is exploited by farmers to produce better plant products.
• Ex: maize
teosinte.wisc.edu/.../Maize-teosinte.jpg
![Page 23: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/23.jpg)
Reducing World Hunger and Malnutrition/The Debate over plant
Biotechnology
• Genetically modified plants have the power to decrease world hunger by growing in more diverse landscapes and being altered to have more nutritional value.
• Ex: “Golden rice” versus ordinary rice. • Golden color and increased nutritional value of golden rice is a result of the production of beta-carotene. This was made possible by genetic engineering.
• Risks of GM plants: transporting allergens, effects on nontarget organisms, and the escaping of virus/herbicide resistant genes to neighboring weed. • So far, the good seems to outweigh the bad.
![Page 24: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/24.jpg)
Haploid and Diploid Generations take turns producing each other diploid, or sporpohyte, produces haploid spores by
mitosis
The spores divide giving rise to gametophytes
Fertilization produces diploid zygotes which divide forming new sporophytes
![Page 25: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/25.jpg)
The sporophyte generation is the dominant generation because they are the largest living plants They develop into flowers
The gametophytes shrink over time They rely on the sporophytes for nutritional purposes
![Page 26: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/26.jpg)
Flowers Male and Female gametophytes develop the anthers
and ovules
In pollination the sperm is brought to the ovule which contains the female gametophyte
The actual fertilization occurs within the ovule of the ovary which develops seeds This allows the ovary to become a fruit
![Page 27: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/27.jpg)
Flower Structure
Four main organs: sepals, petals, stamens, and carpels
Stamens and carpels are reproductive
Sepals and petals are sterile
If two or more carpels are present they conjoin resulting in a many chambered ovary
Anther: stalk like structure; ovary located at base
Stigma: collects pollen
Sepals enclose the floral bud serving as protection before opening
http://images.google.com/imgres?imgurl=http://andromeda.cavehill.uwi.edu/
![Page 28: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/28.jpg)
Gametophyte Development and Pollination
Sporangia- structure on the anther and ovules where spores are produced
Pollen grains are made up of mature male gemetophytes that are enclosed by a spore wall
Found in the microsporangia, or pollen sacs
The female gametophyte is found within the ovule
![Page 29: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/29.jpg)
Pollination is the transfer of pollen from anther to stigma Results if a pollen tube structure Purpose is to grow and digest down ovary and to
release sperm within embryo sac
This fertilizes the egg Embryo -> seed -> fruit containing seed
The fruit disperses seeds which germinate and develop into seedlings
![Page 30: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/30.jpg)
Development Microsporocytes form four haploid microspores
These develop into haploid male gametophytes The microspore does through mitosis and cytokinesis
This results in a generative cell and tube cell which make up the pollen grain
![Page 31: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/31.jpg)
Megasporocytes grows resulting in four haploid megaspores
In some species the megaspore grows and divides by mitosis but not cytokinesis May form a multicellular female gametophyte
Contains 3 cells: 1 egg and 2 synegrids
Synegrids attract and guide pollen tubes to the embryo sac
there are also two nuclei at the other end of the cell that are not separate and share cytoplasm embryo sacs
These result in two integuments that form a seed
![Page 32: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/32.jpg)
Mechanisms that Prevent Self-Fertilization
Sexual reproduction ensures that there will be genetic diversity among offspring
“Selfing” refers to self-fertilization in plants Ensures that seed will develop
![Page 33: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/33.jpg)
Ensuring that the egg and sperm cells come from different parents is a mechanism that inhibits self fertilization
Dioecious plants cannot self fertilize because they have either staminate or carpellate flowers
![Page 34: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/34.jpg)
Flowers with functional stamen and carpels have organs that mature at different rates An animal pollinator would not transfer pollen from
the anther to a stigma of the same flower
![Page 35: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/35.jpg)
Self Incompatibility The ability of a plant to reject its own pollen
Also, in some cases, the pollen of similar plants
If pollen were to land on the stigma of a flower on the same plant a biochemical would prevent the pollen from developing and fertilizing an egg
![Page 36: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/36.jpg)
The S gene Two types of self-incompatibility
Gametophytic Sporphytic
![Page 37: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/37.jpg)
Gemetophytic S- allele blocks fertilization
S1 pollen grain from S1S2 parent will not fertilize the egg of an S1S2 flower
It will however fertilize the egg of and S2S3 flower
The RNA hydrolyzing enzymes will destroy the RNA if it enters the pollen tube
![Page 38: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/38.jpg)
Sporophytic S-allele gene produced in tissues of parental
sporophyte blocks fertilization
S1 and S2 pollen grains from S1S2 parents cannot fertilize eggs of S1S2 flowers or S2S3 flowers
Involves a signal transduction pathway in the epidermal cells Prevent germination of pollen grain
![Page 39: Angiosperm Reproduction - Wikispacesdavisonscience.wikispaces.com/file/view/Ch+38+Angiosperm... · Angiosperm Reproduction . ... more specialized types of cells (regeneration of lost](https://reader030.vdocument.in/reader030/viewer/2022021510/5aae771b7f8b9a3a038c35f6/html5/thumbnails/39.jpg)
Special Circumstances Plant breeders will hybridize different crop varieties
to combine the best traits and to get sufficient results
This can result in inbreeding
May cause plants that are able to self fertilize to lose that characteristic.