Plant Flowers
What are the role of flowers for plants?
Role of flowers Sexual recombination - perpetuation of the species
Role of flowers Sexual recombination - perpetuation of the species Attract pollinators
Role of flowers Sexual recombination - perpetuation of the species Attract pollinators Provide nectar for pollinators
Role of flowers Sexual recombination - perpetuation of the species Attract pollinators Provide nectar for pollinators Formation of fruit
Parts of the Flower - Receptacle Attachment point for flower
Parts of the Flower - Receptacle Attachment point for flower Serves as base for flower
Parts of the Flower - Receptacle Attachment point for flower Serves as base for flower Some fruits are mostly receptacle tissue i.e. apple, pear
Nectarines Found at base inside of flower
Nectaries Found at base inside of flower Sugar solution - nectar
Nectaries Found at base inside of flower Sugar solution - nectar Attractant for pollinators
Nectaries Found at base inside of flower Sugar solution - nectar Attractant for pollinators Pollinators move pollen between flowers in recovery of nectar
Parts of the flower - sepals Protect developing flower bud
Parts of the flower - sepals Protect developing flower bud When flower opens, peel away from bud
Parts of the flower - sepals Protect developing flower bud When flower opens, peel away from bud Modified leaves - mostly green, can be colored in some flowers
Parts of the flower - sepals Protect developing flower bud When flower opens, peel away from bud Modified leaves - mostly green, can be colored in some flowers Collectively known as calyx
Parts of the flower - petals Collectively also called corolla
Parts of the flower - petals Collectively also called corolla Can be fused together - fused corolla
Parts of the flower - petals Collectively also called corolla Can be fused together - fused corolla Often very colorful
Parts of the flower - petals Collectively also called corolla Can be fused together - fused corolla Often very colorful Various shapes, numbers, and arrangements
Parts of the flower - petals Collectively also called corolla Can be fused together - fused corolla Often very colorful Various shapes, numbers, and arrangements Attractant for pollinators, guides pollinators to nectar sources
Parts of the flower - stamen Male portion of flower
Parts of the flower - stamen Male portion of flower Filament - support stalk for anthers
Parts of the flower - stamen Male portion of flower Filament - support stalk for anthers Anthers - generate, support, and disperse pollen grains
Parts of the flower - stamen Male portion of flower Filament - support stalk for anthers Anthers - generate, support, and disperse pollen grains Pollen grains - chromosome number half of other plant cells
Parts of the flower - pistil Female portion of flower
Parts of the flower - pistil Female portion of flower Stigma - attachment point for pollen grains
Parts of the flower - pistil Female portion of flower Stigma - attachment point for pollen grains Style - support for stigma, pollen tube from pollen grains travels down center
Parts of the flower - pistil Female portion of flower Stigma - attachment point for pollen grains Style - support for stigma, pollen tube from pollen grains travels down center Ovary - location where ovules (egg cells) are located, will become fruit tissue
Grass flowers Has pistil and stamens
Grass flowers Has pistil and stamens Does not have petals or sepals
Grass flowers Has pistil and stamens Does not have petals or sepals
Complete flowers Has all 4 parts - sepals, petals, stamens, pistil
Incomplete flowers Missing one or more parts
Incomplete flowers Missing one or more parts Perfect - has sexual parts - stamens and pistil, missing sepals and/or petals
Incomplete flowers Missing one or more parts Imperfect - missing either pistil or stamens Staminate flowers - stamens only Pistillate flowers - pistil only
Plants with imperfect flowers Monoecious Flowers with pistil only, flowers with stamens only, located on same plant Ex. Corn, cucurbits
Plants with imperfect flowers Dioecious Plants have either flowers with pistil only or stamens only. Male and female plants Ex. Holly, asparagus, hops
What is pollination and how does pollination occur?
Pollination is the movement of pollen from anthers to stigma
Pollination Self-pollination - pollination occurs within the same flower or among flowers of the same plant
Pollination Self-pollination - pollination occurs within the same flower or among flowers of the same plant Some flowers are self- pollinated before they open
Pollination Cross-pollination - pollination occurs between flowers of different plants
Pollination Cross-pollination - pollination occurs between flowers of different plants Plants have developed strategies to prevent self-pollination and ensure cross-pollination
Pollination vectors Wind - light weight pollen grains, causes human allergies
Pollination vectors Wind - light weight pollen grains, causes human allergies Insects - attaches insect body, moved in insects attempt to get nectar
Pollination vectors Wind - light weight pollen grains, causes human allergies Insects - attaches insect body, moved in insects attempt to get nectar Birds - when retrieving nectar
Pollination vectors Wind - light weight pollen grains, causes human allergies Insects - attaches insect body, moved in insects attempt to get nectar Birds - when retrieving nectar Humans - controlled crosses
What is plant fertilization and how does it occur?
Fertilization is the union of nuclei from the pollen grains and the egg cells that results in the formation of a zygote
Process of fertilization Pollen attaches to stigma
Process of fertilization Pollen attaches to stigma Pollen tube grows through style, ovary, and attaches to ovule (egg cells)
Process of fertilization Pollen attaches to stigma Pollen tube grows through style, ovary, and attaches to ovule (egg cells) Pollen nuclei travel through pollen tube to ovule
Process of fertilization Pollen attaches to stigma Pollen tube grows through style, ovary, and attaches to ovule (egg cells) Pollen nuclei travel through pollen tube to ovule Pollen nuclei unite with egg nuclei
Process of fertilization Pollen attaches to stigma Pollen tube grows through style, ovary, and attaches to ovule (egg cells) Pollen nuclei travel through pollen tube to ovule Pollen nuclei unite with egg nuclei Zygote begins to develop
Pick 3 plants and answer the following questions? Are your plants flowering? If so, do they have complete flowers? If not, what type of flowers do they have? How many sepals, petals, stamens, and pistils does each flower have? Can you tell how they are is pollinated?