AP BIO HW #3 Plants and the Colonization of Land

Diagram the life cycle of a moss including gamete production, fertilization, and spore production.

1) separate male and female gametophytes with antheridia and archegonia. 2) sperm swims to archegonium and fertilizes egg 3) diploid zygote divides by mitosis and develops into an embryonic sporophyte. 4) sporophyte grows from archegonium and remains attached. 5) top of sporophyte is sporangium where meiosis occurs and haploid species develop spores scatter. 6) spores germinate by mitotic development 7) haploid pojonema continue to grow and differentiate eventually forming sexually mature gametophytes, completing the life cycle.

Diagram the life cycle of a fern including spore production, gamete production and fertilization.

1) sperm production- in sporangium from the sporophyte 2) gamete production- from the antheridium and archegonium on the gametophyte 3) fertilization-eggs(n) + sperm(n) becomes zygote(2n) and grows to become new sporophyte.

Distinguish among spore, sporophyte, sporophyll and sporangium.

A spore is a haploid cell that produces the gametophyte. A sporophyte is a multicellular diploid form resulting from the union of gametes, produces spores. Sporophyll is where sporangia is found, leaves that are specialized for reproduction. Sporangium is the capsule in which meiosis occurs and haploid spores develop.

Explain how bryophytes are still tied to water.

Bryophytes are still tied to water because they are nonvascular and thus don't have vascular tissue to transport water and nutrients. Because of this, they are usually found in moist locations. Those plants also need water to reproduce, for their sperm, like most green algae, are flagellated and must swim from the antheridium to the archegonium to fertilize their egg.

List characteristics that distinguish plants from organisms in the other kingdoms.

Characteristics that distinguish plants from organisms in other kingdoms include that they are eukaryotic, autotrophic (photosynthetic) organisms with true organs and tissues. Individual cells are surrounded by a cellulose cell wall, non-motile having alternation of generations life cycle, and store food as starch.

Provide evidence that suggests the division Bryophyta is a phylogenetic branch separate from vascular plants.

Evidence that suggests the division that Bryophyta is a phylogenetic branch separated from vascular plants is that the life cycle is different. The haploid gametophyte is the dominant generation in mosses and other bryophytes; the sporophytes are smaller and depend on the gametophyte for water and nutrients.

Distinguish between homosporous and heterosporous.

Homosporous produces a single type of spore. each spore developing into a plant with both sex organs. Heterosporous produces 2 types of spores 1) megaspores-female with archegonia. 2)microspores-male with antheridia.

Distinguish between the categories division and phylum.

Plant biologists use the term division for the major plant groups within the plant kingdom. This taxonomic category corresponds to phylum, the highest unit of classification within the animal kingdom. Divisions, like phyla are subdivided into classes, orders, families, and genera.

Provide evidence to defend the position that plants evolved from green algae.

Plants evolved from green algae, and evidence that would defend that position include that they both contain chlorophyll a and b. Both store excess carbohydrates as starch. Both have cellulose in their cell walls. Based on RNA sequencing, scientists have found that they are most closely related to charophytes, a green algae.

Describe adaptations of vascular plants, including modifications of the life cycle and modifications of the sporophyte, that have contributed to their success on land.

The adaptations of vascular plants, including modifications of the life cycle and modifications of the sporophyte that have contributed to their success on land are regional specialization of the plant body (roots, stems, laves), structural support- lignin embedded into cellulose, vascular system- xylem(water) and phloem(food), pollen-eliminated need for water, to transport gametes, seeds increased dominance of diploid sporophyte.

List and distinguish among three division of Bryophyta.

The divisions of Bryophyta are mosses, liverworts and hornworts. 1) Mosses- most familiar bryophytes. A mat of moss consists of many plants growing in a tight pack, helping to hold one another up. 2) Liverworts are even less conspicuous plants than mosses. The bodies of some are divided into lobes, giving an appearance that must have reminded someone of the lobed liver of an animal. 3) Hornworts resemble liverworts but are distinguished by their sporophytes, which are elongated capsules that grow like horns from the manlike gametophyte.

Describe four major periods of plant evolution that opened new adaptive zones on land.

The fossil record chronicles four major periods of plant evolution, which are also evident in the diversity of contemporary plants. Each period was an adaptive radiation that followed the evolution of structures that opened new adaptive zones on the land. 1) associated with the origin of plants from aquatic ancestors, green algae. 2) the diversification of vascular plants 3) began with the origin of the seed, a structure that advanced the colonization of land by further protecting plant embryos from desiccation and other hazards. 4) the emergence of flowering plants

Point out the major life cycle differences between mosses and ferns.

The major life cycle differences between mosses and ferns is that sporopollenin in ferns, not mosses.

Describe how coal is formed and during which geological period the most extensive coal beds were produced.

The most extensive coal beds were produced in the carboniferous period. Coal is formed as a result of organic rubble of the seedless plants accumulating as peat, and later it was covered by the sea and sediments. Heat and pressure transformed the peat into coal.

List and distinguish among the four extant divisions of seedless vascular plants.

Three extant (not extinct) divisions of seedless vascular plants are lycophyta, spenophya, and pTerophyta. 1) lycophyta are the club mosses and ground pines Rhizomes and true leaves. 2) sphenophyta are the horsetails that live in damp locations with flagellated sperm. 3) pterophyta are about 12,000 species of ferns. Dominant sporophyte, homosporous, free-living gametophyte and water is needed for fertilization.

Describe two adaptations that made the bryophytes' move onto land possible

Two adaptations that made the bryophytes move onto land possible are that they are covered by a waxy cuticle that helps the body retain water, and their gametes develop within gametangium.

Compare environmental conditions faced by algae in an aquatic environment and plants in a terrestrial environment.

environmental conditions faced by algae in an aquatic environment is that algae that live in water don't need vascular tissue or seeds. Plants that live on lands where its dry need seeds and vascular tissue to survive most effectively.