Seeds and Fruits Types & Dispersal copyright cmassengale Seeds and Fruit • Fruits are formed by seed plants to aid in dispersing seeds • A seed contains the developing plant embryo in a protective coat (testa) • Seeds form from ovules fertilized in the ovary • Ovaries with seeds ripen into dry or fleshy fruits copyright cmassengale • • • • Parts of a Seed External seed coat or testa Developing plant embryo Stored food called endosperm Seeds may be in one part (monocot) or two parts (dicots) DICOT MONOCOT copyright cmassengale Parts of a Seed copyright cmassengale Gymnosperm Seed • A single fertilization produces the diploid (2n) embryo • The food source is the haploid megagametophyte copyright cmassengale Flowering plant seed In angiosperms (flowering plants) there is DOUBLE _ Which produces a diploid (2n) and, A triploid (3n) Endosperm is the food source copyright cmassengale Dicot vs monocot seed Dicot has two cotyledons (like bean) Endosperm (food) is kept in the _ Monocot has one which absorbs the endosperm tissue during germination (corn) copyright cmassengale Fruit In flowering plants – Fruit is a mature, ripened o _ that contains the seeds Pericarp – the ovary wall Fruit types A Simple B Aggregate C Multiple copyright cmassengale ovary A Simple fruit A Simple fruit – develops from a ovary of a single flower Simple fruits can be either fleshy or dry when mature Simple fleshy fruit _ copyright cmassengale Simple fleshy fruit Berry – entire fruit wall is soft and fleshy at maturity Inside is slimy For example, grapes, tomato, etc _ is a berry with tough, leathery rind (peel) Examples: oranges, lemons, other citrus copyright cmassengale Simple fleshy fruit: pepo – also a fleshy fruit with a tougher outer rind All member of the squash family: pumpkin, melons, cucumbers copyright cmassengale Simple fleshy fruit: pome Pomes: most of the fleshy part of pomes develops from the enlarged base of the perianth (corolla and calyx) that has fused with the ovary wall Pomes include _ copyright cmassengale Simple dry fruit: capsule Simple dry fruits are dry (not fleshy) at maturity Simple dry fruits that open at maturity include: capsules and legumes Capsule – fruit is dry at maturity and splits open along several seams Example: Cotton copyright cmassengale Simple dry fruit: Legumes Legumes are dry at maturity and split open along _ seams Examples: pea pods, bean pods, peanut copyright cmassengale Simple dry fruits Simple dry fruits that NOT open at maturity include Caryopsis: seed coat is fused to the ovary wall (cereal grains like ) Nuts: single-ovary wall and seed coat remain separate, ovary wall is very hard (acorns) copyright cmassengale B _ fruit develops from one flower with many separate pistils/carpels, all ripening simultaneously Examples: strawberry, raspberries, blackberries copyright cmassengale C Multiple fruit Multiple fruit develops from ovaries of several flowers borne/fused together on the same stalk For example: copyright cmassengale What is the purpose of the fruit? The main function of the fruit is to disperse the seeds Dispersal is important because It spreads the progeny in order to colonize new environments Reduces for resources with parents Reduces the chances of predators destroying all of the plant’s yearly seed production Four types of seed dispersal: A Self dispersal B dispersal C Water dispersal D _ dispersal copyright cmassengale A Self dispersal Plants disperse their seeds by forceful ejection – explosive fruits! Witch hazel, squirting cucumber (jet propulsion) copyright cmassengale Self dispersal The peanut plant sows (buries) its own seeds! Geocarpic: carpel grows inside the earth (soil) copyright cmassengale B Wind dispersal Fruit and seeds may have special devices for wind dispersal Plumes catch wind currents: Dandelion Trees take advantage of their great heights for wind dispersal Fruits with wings are used to slow the descent to land: maple, ash fruit copyright cmassengale C _ Dispersal Fruits and/or seeds use flotation devices to travel by water (in rivers, oceans, etc.) Fruit may have air spaces and corky floats: for example copyright cmassengale D Animal dispersal Plants have _ with animals to accomplish seed dispersal Many plants depend on animals for seed dispersal; they may offer a nutritional reward Animals learn to recognize ripened fruit colors Fleshy fruits eaten and dispersed with feces copyright cmassengale Animal dispersal Some dry fruit attach and cling to animals (they hitchhike on the animals) Some have Velcro-like hooks that cling to animal fur (burdock, cockleburs) Others have sticky substances that stick to host (mistletoe) copyright cmassengale Further Study on Seed Dispersal What carries the dandelion seeds for miles? What feature of trees gives them a particular advantage when dispersing seeds by air? How does the squirting cucumber disperse its seeds? Although plants use wind and water, what most plants use as carriers for their seeds? Blackberries on a tree not ripen simultaneously, why? What plant elephants help to disperse? How they it? What percentage of these seeds germinate in elephant dung? Why? copyright cmassengale [...]...Simple fleshy fruit: drupe 3 _ type – outer part of fruit wall is soft and fleshy, inner part is hard and stony For example: copyright cmassengale Simple fleshy fruit: pepo 4 – also a fleshy fruit with a tougher outer rind All member of the squash family: pumpkin, melons, cucumbers copyright cmassengale Simple fleshy fruit: pome 5 Pomes: most of the fleshy... the ovary wall Pomes include _ copyright cmassengale Simple dry fruit: capsule Simple dry fruits are dry (not fleshy) at maturity Simple dry fruits that open at maturity include: capsules and legumes Capsule – fruit is dry at maturity and splits open along several seams Example: Cotton copyright cmassengale Simple dry fruit: Legumes Legumes are dry at maturity and split open along _ seams... simultaneously Examples: strawberry, raspberries, blackberries copyright cmassengale C Multiple fruit Multiple fruit develops from ovaries of several flowers borne/fused together on the same stalk For example: copyright cmassengale What is the purpose of the fruit? The main function of the fruit is to disperse the seeds Dispersal is important because 1 It spreads the progeny in order to colonize new... dispersal copyright cmassengale A Self dispersal Plants disperse their seeds by forceful ejection – explosive fruits! Witch hazel, squirting cucumber (jet propulsion) copyright cmassengale Self dispersal The peanut plant sows (buries) its own seeds! Geocarpic: carpel grows inside the earth (soil) copyright cmassengale B Wind dispersal Fruit and seeds may have special devices for wind dispersal Plumes catch... Plumes catch wind currents: Dandelion Trees take advantage of their great heights for wind dispersal Fruits with wings are used to slow the descent to land: maple, ash fruit copyright cmassengale C _ Dispersal Fruits and/or seeds use flotation devices to travel by water (in rivers, oceans, etc.) Fruit may have air spaces and corky floats: for example copyright cmassengale D Animal dispersal... ripened fruit colors Fleshy fruits eaten and dispersed with feces copyright cmassengale Animal dispersal Some dry fruit attach and cling to animals (they hitchhike on the animals) Some have Velcro-like hooks that cling to animal fur (burdock, cockleburs) Others have sticky substances that stick to host (mistletoe) copyright cmassengale Further Study on Seed Dispersal What carries the dandelion seeds. .. trees gives them a particular advantage when dispersing seeds by air? How does the squirting cucumber disperse its seeds? Although plants use wind and water, what do most plants use as carriers for their seeds? Blackberries on a tree do not ripen simultaneously, why? What plant do elephants help to disperse? How do they do it? What percentage of these seeds germinate in elephant dung? Why? copyright cmassengale... Examples: pea pods, bean pods, peanut copyright cmassengale Simple dry fruits Simple dry fruits that do NOT open at maturity include Caryopsis: seed coat is fused to the ovary wall (cereal grains like ) Nuts: single-ovary wall and seed coat remain separate, ovary wall is very hard (acorns) copyright cmassengale B _ fruit develops from one flower with many separate pistils/carpels, .. .Seeds and Fruit • Fruits are formed by seed plants to aid in dispersing seeds • A seed contains the developing plant embryo in a protective coat (testa) • Seeds form from ovules... fruit A Simple fruit – develops from a ovary of a single flower Simple fruits can be either fleshy or dry when mature Simple fleshy fruit _ copyright cmassengale Simple fleshy fruit. .. germination (corn) copyright cmassengale Fruit In flowering plants – Fruit is a mature, ripened o _ that contains the seeds Pericarp – the ovary wall Fruit types A Simple B Aggregate C Multiple