Kingdom Plantae The Story of the Plants

Consider an aquatic green algae: In water: Materials are transported into and out of the organism through simple osmosis and diffusion Cells won’t dry out Reproductive products (egg/sperm/spores) are just released and get dispersed by the currents Buoyancy holds algae upright in the water

Making the move to dry land… Plants needed to overcome some problems in order to be able to survive on land They needed to address: How to move materials into, out of, and throughout body How to prevent drying out How to support their structure How to disperse reproductive products without water

Mosses Rely on surrounding moisture Nonvascular – have no effective way of transporting water and nutrients so size is limited. Are restricted to moist environments like swamps/bogs.

Moss

Tannic acid from decaying peat moss makes bogs acidic.

Ferns Vascular – have a way of transporting water and materials throughout themselves. Xylem – tissues that transport water and dissolved materials up from the roots Phloem – tissues that transport sugars down from leaves Reproduce with spores, not seeds

Ferns

Reproduce by spores Spores are produced in sori on the underside of the leaf.

Gymnosperms (Conifers) Reproduce from seeds and are not dependent on water – next level of complexity Seeds are considered to be “naked”, meaning unprotected. Also have a waxy cuticle to prevent moisture loss from leaves

Gymnosperms

Angiosperms Considered to be the most advanced plants. Also reproduce by seeds, but seeds are protected inside a flower or fruit. This provides an energy source for the developing embryo Range of colors, nectars, scents attract insects which aid in cross-pollination.

Angiosperms

Honey bee with pollen sacs full as it sips nectar Honey bee with pollen sacs full as it sips nectar. Hummingbird sipping nectar from a flower.