160 ❯ STEP 4. Review the Knowledge You Need to Score High
What are flowers, really? Are they just another visually pleasing structure? No... they
are so much more. Flowers are the main tools for angiosperm reproduction. Do not waste
too much time learning every little part of a flower. Here are the most important parts to
remember:
Stamen:male structure composed of an anther,which produces pollen.
Carpel:female structure that consists of an ovary,astyle,and a stigma.The stigma func-
tions as the receiver of the pollen, and the style is the pathway leading to the ovary.
Petals:structures that serve to attract pollinators to help increase the plant’s reproductive success.
Below is a quick display that lists many of the major evolutionary trends observed during
the phylogenetic development of plants.Remember these evolutionary trends seen in plants!- Dominant gametophyte generation →dominant sporophyte generation
- Nonvascular →vascular
- Seedless →seeds
- Motile sperm →pollen
- Naked seeds →seeds in flowers
Kingdom Fungi
Nearly all fungi are multicellular and are built from filamentous structures called hyphae.
These hyphae form meshes of branching filaments known as a mycelium,which function
as mouthlike structures for the fungus, absorbing food. Many fungi contain septae,which
divide the hyphae filaments into different compartments. The septa have pores, which
allow organelles and other structures to flow from compartment to compartment. Fungi
that do not contain septae are called coenocytic fungi.Fungus walls are built using the
polysaccharidechitin.As was discussed in Chapter 9, Cell Division, the fungus life cycle is
predominately haploid. The only time they are diploid is as the 2nzygote.
The following is a list of fungus-related organisms that you should know:- Zygomycota.Thesecoenocyticandland-dwellingfungi have very few septa and reproduce
sexually. A classic example of a zygomycete is bread mold. - Basidiomycota.These club-shaped fungi are known for their haploid basidiospores and
love of decomposing wood. Famous members include mushrooms and rusts. - Ascomycota.Many members of this group of saprobic fungi live as part of the symbiotic
relationship called lichen.These fungi produce sexual ascospores,which are contained
in sacs. Famous ascomycetes you may have heard of are yeasts and mildews. These are
discussed again in Chapter 19, Laboratory Review. - Lichens. These are formed by a symbiotic association of photosynthetic organisms
grouped together with fungal hyphae (usually anascomycete). The algae member of this
group tends to be cyanobacteriaorchlorophytaand provides the food (sugar from pho-
tosynthesis). The fungus provides protection and drink (water). - Molds.These are asexual, quick-growingfungi known as deuteromycotaor the “imperfect
fungi.” If you check any college refrigerator, you can find many fine samples of this
organism. - Yeasts.These are unicellularfungi that can be asexual orsexual. One member of this
group,Candida,is known to cause yeast infections in humans.
KEY IDEA