Post on 25-Dec-2015
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The life cycle of a plantThe life cycle of a plantRoots grow from a seed.
Leaves start to grow.
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The life cycle of a plantThe life cycle of a plantRoots grow from a seed.
Leaves start to grow.
More leaves grow. Flower buds appear.
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The life cycle of a plantThe life cycle of a plant
Roots grow from a seed.
Leaves start to grow.
More leaves grow. Flower buds appear.
The flowers open.
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The life cycle of a plantThe life cycle of a plantThe petals die. The flowers make a fruit with seeds inside.
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The life cycle of a plantThe life cycle of a plantThe petals die. The flowers make a fruit with seeds inside.
The fruit dries and falls.
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FruitFruitIn flowering plants In flowering plants FruitFruit is a mature, ripened ovary that is a mature, ripened ovary that
contains the seedscontains the seeds Pericarp Pericarp – the ovary wall– the ovary wall
ovary
Fruit typesFruit types A. SimpleA. Simple B. AggregateB. Aggregate C. MultipleC. Multiple
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Developmental origin of Developmental origin of fruitsfruits
Simple fruit. A simple fruit develops from a single carpel (or several fused carpels) of one flower (examples: pea, lemon, peanut).
(a) Aggregate fruit. An aggregate fruit develops from many separate carpels of one flower (examples: raspberry, blackberry, strawberry).
(b) Multiple fruit. A multiple fruit develops from many carpels of many flowers (examples: pineapple, fig).
(c)
Pineapple fruitRaspberry fruitPea fruit
Stamen
Carpel(fruitlet) Stigma
Ovary
Raspberry flower
Eachsegmentdevelopsfrom thecarpel ofone flower
Pineapple inflorescence
Stamen
CarpelsFlower
OvaryStigma
Stamen
Ovule
Pea flower
Seed
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SIMPLE FRUITSIMPLE FRUIT The mayority of flowering plant have fruit The mayority of flowering plant have fruit
composed of a single ovary. These referred to composed of a single ovary. These referred to as simple fruits.as simple fruits.
When the entire When the entire pericarppericarp (the ovary wall) of (the ovary wall) of simple fruits is fleshy, the fruit is refer to berry.simple fruits is fleshy, the fruit is refer to berry.
Simple fleshy fruits having a stony endocarp Simple fleshy fruits having a stony endocarp (such as peach, plum, olive) are known as (such as peach, plum, olive) are known as drupesdrupes (or (or stone fruitsstone fruits).).
Simple fleshy fruits in which the inner portion of Simple fleshy fruits in which the inner portion of the pericarp forms a dry paperlike “core” are the pericarp forms a dry paperlike “core” are known as pomes (apple, pear, for example).known as pomes (apple, pear, for example).
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Simple fruitSimple fruit•Simple fruit – develops from a single ovary of a single flower.•Simple fruits can be either fleshy or dry when mature
Simple fleshy fruit1. Berry2. Hesperidium3. Drupe4. Pepo5. Pome
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Aggregate FruitAggregate Fruit Aggregate FruitAggregate Fruit develops from one flower develops from one flower
with many separate pistils/carpels, all with many separate pistils/carpels, all ripening simultaneouslyripening simultaneously
Examples: strawberry, raspberries, Examples: strawberry, raspberries, blackberriesblackberries
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C. Multiple fruitC. Multiple fruit Multiple fruitMultiple fruit develops from ovaries of develops from ovaries of
several flowers borne/fused together on several flowers borne/fused together on the same stalkthe same stalk
For example: pineappleFor example: pineapple
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How Fruits FormHow Fruits Form Fruits are mature ovaries.Fruits are mature ovaries.
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Simple fleshy fruitSimple fleshy fruit
1. Berry1. Berry 2. Hesperidium2. Hesperidium 3. Drupe3. Drupe 4. Pepo4. Pepo 5. Pome5. Pome
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Simple fleshy fruitSimple fleshy fruit 1. Berry1. Berry – entire fruit wall is – entire fruit wall is
soft and fleshy at maturity. soft and fleshy at maturity. Inside is slimy.Inside is slimy.
For example, grapes, tomato, For example, grapes, tomato, etc.etc.
2. Hesperidium 2. Hesperidium is a berry is a berry with tough, leathery rind (peel) with tough, leathery rind (peel)
Examples: oranges, lemons, Examples: oranges, lemons, other citrus.other citrus.
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Simple fleshy fruit: Simple fleshy fruit: drupedrupe
3. Drupe type3. Drupe type – outer part of fruit wall is – outer part of fruit wall is soft and fleshy, inner part is hard and soft and fleshy, inner part is hard and stonystony
For example: cherry, plum, peach, and For example: cherry, plum, peach, and apricotapricot
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Simple fleshy fruit: Simple fleshy fruit: pepopepo
4. Pepo 4. Pepo – also a fleshy fruit with a tougher – also a fleshy fruit with a tougher outer rindouter rind
All member of the squash family: pumpkin, All member of the squash family: pumpkin, melons, cucumbersmelons, cucumbers
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Simple fleshy fruit: Simple fleshy fruit: pomepome
5. Pomes5. Pomes: most of the fleshy part of pomes : most of the fleshy part of pomes develops from the enlarged base of the develops from the enlarged base of the perianth (corolla and calyx) that has fused perianth (corolla and calyx) that has fused with the ovary wallwith the ovary wall
Pomes include apple, and pearPomes include apple, and pear
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Simple dry fruit: Simple dry fruit: capsulecapsule
Simple dry fruits Simple dry fruits are dry (not fleshy) at are dry (not fleshy) at maturity. Simple dry fruits that open at maturity. Simple dry fruits that open at maturity include:maturity include: capsules and legumescapsules and legumes
CapsuleCapsule – fruit is dry at maturity and splits – fruit is dry at maturity and splits open along several seamsopen along several seams
Example: CottonExample: Cotton
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Simple dry fruit: Simple dry fruit: LegumesLegumes
Legumes Legumes are dry at maturity and split open are dry at maturity and split open along two seamsalong two seams
Examples: pea pods, bean pods, peanutExamples: pea pods, bean pods, peanut
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Simple dry fruitsSimple dry fruits Simple dry fruits that do NOT open at Simple dry fruits that do NOT open at
maturity includematurity include CaryopsisCaryopsis: seed coat is fused : seed coat is fused
to the ovary wall (cereal grains to the ovary wall (cereal grains like wheat, corn, barley, rice)like wheat, corn, barley, rice)
NutsNuts: single-ovary wall and : single-ovary wall and seed coat remain separate, seed coat remain separate, ovary wall is very hardovary wall is very hard(chestnut, walnut, acorns)(chestnut, walnut, acorns)
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Dry Fruit Types
Name Characteristics Examples
Follicle Dehiscent; from single carpel that splits down one side at maturity.
Columbine, milkweed
Legume Dehiscent; like follicles, but split down both sides. Pea family (Fabaceae)
Silique Dehiscent; from two fused carpels; at maturity the sides split off, leaving seeds attached to persistent central portion.
Mustard family (Brassicaceae)
Capsule Dehiscent; from compound ovary with either superior or inferior ovary
Poppy family (Papaveraceae)
Achene Indehiscent; small single-seeded fruit, seed lies free in the cavity except for attachment by funiculus (stalk of the ovule).
Buttercup family (Ranunculaceae), buckwheat family (Polygonaceae)
Samara Indehiscent; winged achenes. Elm, ash
Caryopsis Indehiscent; achene-like fruit of grasses; seed coat firmly united to fruit wall.
Grass family (Poaceae)
Cypsela Indehiscent; achene-like, complex; derived from inferior ovary.
Sunflower family (Asteraceae)
Nut Indehiscent; achene-like, with stony fruit wall and derived from compound ovary.
Acorn, hazelnut, pecan
Schizocarp Indehiscent; splits at maturity into two or more one-seeded portions.
Parsely family (Apiaceae), maples (Aceraceae), some others.
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SEEDSEED A A seedseed is a small embryonic plant enclosed in a is a small embryonic plant enclosed in a
covering called the seed coat, usually with some covering called the seed coat, usually with some stored food. stored food.
It is the product of the ripened ovule of It is the product of the ripened ovule of gymnospermgymnosperm and and angiosperm plantsangiosperm plants which which occurs after fertilization. occurs after fertilization.
The formation of the seed completes the process The formation of the seed completes the process of reproduction in seed plants (started with the of reproduction in seed plants (started with the development of flower and pollination), with the development of flower and pollination), with the embryo developed from theembryo developed from the zygote zygote and the seed and the seed coat from the integuments of the ovule.coat from the integuments of the ovule.
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SeedSeed completes the prosess of reproduction completes the prosess of reproduction initiated in the flower, and it always consists of initiated in the flower, and it always consists of an embryo surrounded by seed coats.an embryo surrounded by seed coats.
Double fertilizationDouble fertilization involves involves
a. fusion of egg and sperm nuclei to form a. fusion of egg and sperm nuclei to form
a zigote nucleus, anda zigote nucleus, and
b. fusion of polar nuclei with second b. fusion of polar nuclei with second
sperm nucleus to form a primary sperm nucleus to form a primary
endosperm nucleusendosperm nucleus
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Seed includes three basic Seed includes three basic parts:parts:
(1) an embryo, (1) an embryo, (2) a supply of nutrients for the embryo, (2) a supply of nutrients for the embryo, (3) a seed coat.(3) a seed coat.
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How are seeds made?How are seeds made?
The stamen inside the flower makes pollen.
stamen
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How are seeds made?How are seeds made?
The stamen inside the flower makes pollen. Plants need pollen from a different flower to make seeds. stamen
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How are seeds made?How are seeds made?
The stamen inside the flower makes pollen. Plants need pollen from a different flower to make seeds. When the flower is pollinated the seeds start to grow.
stamen
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How are seeds made?How are seeds made?
Some flowers need insects to pollinate them.
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How are seeds made?How are seeds made?
Some flowers need insects to pollinate them. The pollen sticks to bees or insects.
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How are seeds made?How are seeds made?
Some flowers need insects to pollinate them. The pollen sticks to bees or insects. The pollen is taken to other flowers.
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How are seeds made?How are seeds made?
Some flowers need insects to pollinate them. The pollen sticks to bees or insects. The pollen is taken to other flowers.
Plants like grass and trees do not have bright petals.
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How are seeds made?How are seeds made?
Some flowers need insects to pollinate them. The pollen sticks to bees or insects. The pollen is taken to other flowers.
Plants like grass and trees do not have bright petals. Their pollen is blown by the wind.
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Parthenocarpy
Parthenocarpy: production of fruit without fertilization i.e. pineapple, navel orange, seedless grape.
Auxins, a plant hormone, or synthetically derived growth substances can be applied to encourage parthenocarpy. From the first page, we saw how genetic manipulation can be used to also produce such fruit.
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EpigeousIn epigeous (or epigeal) germination, the hypocotyl elongates and forms a hook, pulling rather than pushing the cotyledons and apical meristem through the soil. Once it reaches the surface, it straightens and pulls the cotyledons and shoot tip of the growing seedlings into the air. Beans and papaya are examples of plant that germinate this way
HypogeousAnother way of germination is hypogeous (or hypogeal) where the epicotyl elongates and forms the hook. In this type of germination, the cotyledons stay underground where they eventually decompose. Peas, for example, germinate this way
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DormancyDormancy Many live seeds have dormancy, meaning they will not Many live seeds have dormancy, meaning they will not
germinate even if they have water and it is warm enough germinate even if they have water and it is warm enough for the seedling to grow. for the seedling to grow.
Dormancy is broken or ended by a number of different Dormancy is broken or ended by a number of different conditions. Environmental factors like light, temperature, conditions. Environmental factors like light, temperature, fire, ingestion by animals and others are conditions that fire, ingestion by animals and others are conditions that can end seed dormancy. can end seed dormancy.
Internally seeds can be dormant because of plant Internally seeds can be dormant because of plant hormones such as absciscic acid, which affects seed hormones such as absciscic acid, which affects seed dormancy and prevents germination, while the dormancy and prevents germination, while the production and application of the hormone gibberellin production and application of the hormone gibberellin can break dormancy and induces seed germinationcan break dormancy and induces seed germination
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Seed DispersalSeed Dispersal WindWind
The plant itself - TumbleweedThe plant itself - Tumbleweed
WaterWater AnimalsAnimals
StorageStorage Ingestion, external transport (hooks - barbs)Ingestion, external transport (hooks - barbs)
Explosions (dehiscence)Explosions (dehiscence)
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Seed Dispersal
• The wind blows the plant and the seeds fall out.
• The fruit breaks open. The seeds fall.
• Some seeds have parachutes. The wind blows the seeds away.
• Some seeds have wings. They fly through the air for a long way.
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Seed Dispersal Animals help disperse
some seeds.
Fleshy fruits eaten and dispersed with feces
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Seed DispersalSeed Dispersal Importance of:Importance of:
ColonizationColonization Survival of speciesSurvival of species Wildlife preservationWildlife preservation Community structure (assemblages of Community structure (assemblages of
plants and animals)plants and animals) Global climateGlobal climate Environmental qualityEnvironmental quality