bio 26- seed plants

seed plant qualities

vascular, live on land, have seeds

seed plant sporophyte

dominant, gametophyge is microscopic- not free living

pollen

male gametophyte, produces sperm, released from sporophyte, dispersed by wind, don’t need water fertilization

seeds protect

sporophyte embryo, delay germination until conditions are good

seed plant types

gymnosperms, angiosperms

gymnosperms

“naked seeds”, no ovary around seed, no fruit/flowers, modified leaves (sporophylls) surround seeds, form strobilus

strobilus

arrangement of sporophylls around a stalk (pinecone) (can look like fruit)

monoecious

male +female reproductive organs on same plant (pinecone)

dioecious

male + female reproductive organs on separate plant

major groups of gymnosperms

phylum confierophyta, phylum cycadophyta, phylum ginkgophyta, phylum gnetophyta

phylum confierophyta (conifers)

monoeciousm mostly evergreen, some are deciduous, larche

phylum cycaphyta (cycadi)

large palm like leaves, large cones, all are dioecious

phylum ginkgophyta (ginkgoes)

dioecious, deciduous, tolerant of pollution (planted in intercity location)

phylum gnetophyta (gneophytes)

diverse members

conifer life cycle

sporophyte (tree) has female (pinecones) and male (cones) strobilli, produce female/male gametophytes, pollen dispersed by wind, reaches female cone, develop pollen tube, delivers sperm to egg, zygote makes embryo (sporophyte) within seed, seeds disperse grow into tree

angiosperms

vascular land plant, has flowers, flowers host gametophytes, attract pollinators, made them dominant, fruit

flower anatomy

sepals/calyx, stamen/androecium, gynoceium/carpel/pistil

sepals/calyx

hold up petals of flower (petals together are corolla)

stamen/androecium

male structure, has a filament that supports anther; another produces pollen

gynoceium/carpel/pisitl

stigma at top to trap pollen, travels to style, then to ovules in the ovary which eggs are and fertilization occurs

perfect flower

has both gynoecium + androecium

monoecious plant

single plant; two unisexual flowers

dioecious plant

distinct male +female plant with unisexual flowers

fruit

fleshy or dry, aids in dispersal (animals eat fruit and poop seeds)

angiosperm life cycle

similar to gymnosperms, double fertilization

angiosperm double fertilization

2 sperm enter, one fertilizes egg, other fertilizes polar nuclei, they combine to make a 3n endosperm

endosperm

fuel for the growing sporophyte in angiosperm

types of angiosperm

basal angiosperms, eudicots/picots, monocots

basal angiosperms

water lily, magnolia, pepper, laurels; small group

eudicots/picots

most trees, cabbage family, beans, peaches

monocots

grasses, palms, rice bananas

monocot qualities

one cotyledon, parallel leaf veins, vascular bundles

eudicots

two cotyledons, netlike leaf viens, vascular bundles around the outside

angiosperms experience coevolution with herbivores

defenses against herbivory, encourages pollination

defense against herbivores

physical protection, chemical compounds, camouflage/mimicry