1 plant reproduction. 2 photoperiodism the critical factor that influences flowering is the number...
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PHOTOPERIODISMPHOTOPERIODISM• The critical factor that
influences flowering is the number of hours of uninterrupted hours of darkness, not the number of daylight hours.
• The flowering response is called photoperiodism.
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PHOTOPERIODISMPHOTOPERIODISM• The beginning of
flower development for each flowering species of plant is in response to the number of hours of darkness.
• This is called the plant’s critical period.
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PHOTOPERIODISMPHOTOPERIODISM• Flowering plants are
placed into four different flowering groups:
1)Short-day plants2)Long-day plants3)Intermediate-day
plants4)Day-neutral plants
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PHOTOPERIODISMPHOTOPERIODISMShort-Day Plants•These plants flower when their number of hours of darkness are greater than their critical period.•These plants flower in the fall, winter, and spring.
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PHOTOPERIODISMPHOTOPERIODISMLong-Day Plants•These plants flower when their number of hours of darkness are less than their critical period.•These plants flower in the summer.
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PHOTOPERIODISMPHOTOPERIODISMIntermediate-Day Plants•These plants flower when their number of hours of darkness are not too great or too few.•These plants flower in tropical regions.
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PHOTOPERIODISMPHOTOPERIODISMDay-Neutral Plants•These plants flower regardless of the number of hours of darkness as long as there is enough photosynthesis to support growth.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Pollination occurs when the pollen grain of a species of plant lands on the female reproductive structure of the same species.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
The pollen grain then grows a pollen tube through the style of the plant into the ovary where fertilization occurs.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Once fertilization occurs, a seed develops.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Parts of Seeds•Endosperm – a tissue that provides nourishment for the embryo.•Seed Coat – Protective outer covering of the seed.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Germination-When the embryo in a seed starts to grow.
Germination begins when the seed absorbs water either as a liquid or as a gas and the seed swells, breaking the seed coat.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Plants can be identified as monocots or dicots by comparing seed, flower, and leaf structure.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Monocots•Petals in multiples of 3•Leaves have parallel veins and are long and narrow.• Seed has a single cotyledon
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Dicots•Petals in multiples of 4 or 5•Leaves have a netted, veined pattern.•Seed has two cotyledons
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Fruits form primarily from the ovary wall, and in some cases the ovary wall and some flower organs.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Types of fruits:1)Simple fleshy fruits2)Aggregate fruits3)Multiple fruits4)Dry fruits
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Simple fleshy fruits•These fruits contain one or more seeds•Examples are peaches, apples, and tomatoes.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Aggregate fruits•Formed from flowers with multiple female organs that fuse as the fruit ripens.•Examples are strawberries, raspberries and blackberries.
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SEED AND FRUIT SEED AND FRUIT DEVELOPMENTDEVELOPMENT
Multiple fruits•Form from many flowers that fuse as they ripen.•Examples are figs and pineapples.