Biology exam 2

Homospory

Spores are all the same; gametophytes produce both archegonia and antheridia

Fertilization

Union of gametes

Pollination

Arrival of pollen grain at an appropriate landing point, close to a female gametophyte on a sporophyte of the same species

Tracheids- a type of tracheary element found in the xylem of nearly all vascular plants, characterized by tapering ends and walls that are pitted but not perforated/ vessel elements- a type of tracheary element with perforated end walls; found only in angiosperms

Compare and contrast the cells known as vessel elements with those known as tracheids

Mostly aquatic and microscopic; alternation of generations

Compare and contrast the chytrids with other multicellular fungi, focusing on their habitat and life cycle

Coenocytic- continuous and multinucleate/ septate- divided into compartments by chitinous walls. Pores at the center of the septa allow organelles to move in a controlled way between compartments

Compare and contrast the hyphal conditions known as coenocytic and septate. Hypothesize on the usefulness of having large openings between hyphal cells

Both have alternation of generations with multicellular haploid and diploid stages; both also reproduce with spores/ moss is gametophyte and fern is sporophyte

Compare and contrast the life cycle of the moss with that of the fern

Egg or sperm/ fuse to form a zygote

Define and give the function for gametes

Multicellular organs or specialized sex organs/ enclose plant gametes and prevent them from drying out

Define and give the function of gametangia

Cells contained within specialized reproductive organs of the sporophyte/ undergoes meiosis to produce haploid, unicellular spores

Define and give the function of sporangia

Haploid spores develop into gametophytes and diploid spores develop into sporophytes; develops into multicellular haploid organisms/ haploid dispersal units and germinate to form protonema which grows into a new gametophyte

Define and give the function of spores

Enclosed seed/ complex vascular tissue, flowers, double fertilization, enclosed ovules and seeds, fruit

Define angiosperm and list four defining characteristics of these plants

Fruiting strictures

Define basidiomata

Swollen cell at the tip of a specialized hypha

Define basidium

A cell or organism carrying two genetically distinguishable nuclei

Define dikaryon

Fusion of nuclei of two cells

Define karyogamy

Particular strain of species that is incapable of sexual reproduction with another member of same strain but capable of sexual reproduction with members of other strains of the same species

Define mating type

Fusion of cytoplasm of two cells

Define plasmogamy

Growth that contributes to an increase in diameter due to accumulation of xylem(wood)/ provides support for primary growth and facilitates light absorption and seed dispersal

Define secondary growth and explain its significance to the success of seed plants

Female and male functions might interfere with each other (stigma might be placed so as to make it difficult for pollinators to reach the anthers, thus reducing the export of pollen to other flowers)

Describe evolutionary changes to flowers that could function to discourage self-pollination

Cuticle- waxy covering that retards dessication/ stomata- provide breathing space through cuticle/ gametangia- multicellular structures of gametophyte; enclose and protect gametes and embryos/ spore walls- unicellular dispersal unit; produced by sporophyte via meiosis/ mycorrhizae- allows for more efficient uptake and assimilation of nutrients

Describe how land plants are distinguished from green algae

Large, complex leaf of a fern, horsetail, or seed plant with several to many veins

Describe megaphylls and name the plant groups that possess this type of leaf

A small leaf with a single vein, found in club mosses and their relatives

Describe microphylls and name the plant groups that possess this type of leaf

Engulfment of cyanobacterium by larger eukaryotic cell that gave rise to first photosynthetic eukaryotes with chloroplasts

Describe primary endosymbiosis

Coenocytic hyphae that use glucose from their plant partners as their primary energy source, converting it into other, fungus specific sugars that cannot return to the plant

Describe the form and function of an arbuscule of the glomeromycota

Intracellular parasites of animals; greatly reduced, among smallest eukaryotes known; polar tube used to infect hosts

Describe the fungal group known as microsporidia

Most primitive of the extant nonseed vascular plants; sporangia are held in apical strobili; either homosporous or heterosporous/ simple leaves arranged spirally on the stem

Describe the key biological characteristics of the club mosses. Explain how you could recognize such plants today

Largest surviving group of nonseed vascular plants(12,000); advanced vascular structures and can reach great heights; don't produce true wood; root systems are poorly developed; have sporangia/ have large, complex leaves with branching vascular strands

Describe the key biological characteristics of the ferns. Explain how you could recognize such plants today

True roots, sporophytes are large and independent, gametophytes are highly reduced but also independent; exhibits basal growth/ leaves are simple, forming whorls around the stem

Describe the key biological characteristics of the horsetails. Explain how you could recognize such plants today

Oldest surviving plant clade; lack stomata; sporophytes are shorter than mosses and hornworts/ leafy gametophytes

Describe the key characteristic of liverworts. Explain how you could recognize such plants today

Most abundant (15,000 species); have hydroids and leptoids; have apical cell division; have stomata/ thick mats found on damp, cool ground

Describe the key characteristics of mosses. Explain how you could recognize such plants today

Mutualistic relationship(relationship benefits both partners)/ fungi and plant roots/ fungus obtains products of photosynthesis and provides water and minerals to the plant.

Describe the mutualism known as mycorrhizae, name the partners, and state what each contributes to the relationship.

Symbiotic relationship(partners live in close, permanent contact with each other)/ fungus and photosynthetic microorganism(alga or cyanobacteria)/ they make their own food through photosynthesis; can thrive in harsh environments

Describe the mutualistic relationship known as lichen, name the partners, and state what each contributes to the relationship

Saprobes decompose matter/ carbon atoms are returned to the atmosphere in the form of carbon dioxide by fungal respiration.(recycling dead plants and animals) Carboniferous- decomposers largely absent, large quantities of peat remained on the swamp floor and over time were converted into coal/ permian- fungi flourished (demonstrating their hardiness and role in recycling the elements in dead plants and animals)

Describe the role of fungi in the global carbon cycle. Differentiate between the carboniferous and permian periods on the basis of the relative global activity of fungi

Gametangia- nuclei replicate without cell division, resulting in multiple haploid nuclei in both gametangia. 2 gametangia fuse to form a zygosporangium that contains many haploid nuclei of each mating type/ zygospore- only single surviving cell. Rhizopus

Describe the role of gametangia and zygospores in the life cycle of zygospore fungi. Name a common example of a fungus from this group.

Consists of sperm and supporting cells and the walls contain sporopollenin/ look like mickey mouse/ dispersed by wind or animals

Describe the source, structure, and function of the pollen grain

Has seed coat, nutritive tissue, and embryo/ protects embryo, disperses, nourishment, extended period of dormancy

Describe the source, structure, and function of the seed

Presence of a single, platelike chloroplast in each cell and sporophytes that are capable of indeterminate growth/ long, slender horn

Describe the two key characteristics of the hornworts. Explain how you could recognize such plants today

Saprobes, parasites, predators, mutualistic symbionts

Describe the various ecological roles that fungi can have

Because pollen does not need water. It can be carried away by wind or animals

Describe why heterospory is important to seed plants

Filamentous hyphae don't produce large ascomata but can still produce asci and ascospores/ antibiotics. Penicillin

Discuss the biology and importance of sac fungi molds. Provide examples

Unicellular; reproduce asexually by budding/ needed to make bread, beer, and wine. Soy sauce and sake

Discuss the biology and importance of the sac fungi yeast. Provide examples

Cuticle, stomata, gametangia, embryos, pigments, spore walls, mycorrhizae(mutually beneficial association with fungi)

Discuss the evolutionary adaptations found in the most successful land plants

Parasitic- growth depends on a living host (plants and insects)/ pathogenic- sickens or kill host through disease

Distinguish between a parasitic and a pathogenic relationship between a fungus and its host

Ectomycorrhizae- wrap their hyphae around a plant root/ arbuscular- hyphae penetrates the root cell walls and form treelike structures that provide the plant with nutrients

Distinguish between ectomycorrhizae and arbuscular mycorrhizae

Heterospory

Either the megaspore gives rise to the megagametophyte or the microspore develops into a microgametophyte

Liverworts, hornworts, and mosses

Examples of nonvascular plants

Club mosses, horsetails, and ferns

Examples of vascular plants

The other sperm nucleus combines with two other haploid nuclei of the female gametophyte to form a cell with a triploid nucleus/ provides nutrition for the developing embryo

Explain how endosperm forms and discuss its importance in the seed and to humans and other animals

Provides structural support/ plant cell walls/ allows for vertical growth for access to sunlight and dispersal of spores

Explain what lignin does, where it is found, and is importance to the success of plants on land

Glaucophytes- only plant group whose chloroplasts retain peptidoglycan Red algae- contains phycoerythrin Chlorophytes- largest clade of green algae Streptophytes(Coleochaephytes /stoneworts)- closest relatives to land plants

List and provide a key characteristic of five major clades of plants

Provide food rewards and bright colored petals

List some adaptations that flowers have to attract pollinators

Contain chlorophylls a and b/ store their reserve of photosynthetic products as starch in chloroplasts/ eggs retained by parental organism/ plasmodesmata connect cytoplasm of adjacent cells/ growth is apical and branching/ chloroplasts structure/ similar mechanics of cell division

List the features that green algae and land plants have in common

Cycads- vascular tissues, slow growing, dioecious, tissues highly toxic if ingested, often confused with ferns or palms, reproductive structures are Cone-like strobili/ ginkgos- vascular tissues, slow growing, unique fan shaped leaves with parallel venation, dioecious, deciduous, ciliated sperm, tolerates urban pollution, leaf extract taken by many to enhance memory and treat dementia/ gnetophytes- vascular tissues, mostly dioecious, consists of 3 genera/ conifers- vascular tissues, small needle-like evergreen leaves help reduce water loss and deal with short growing season, produce scented resin(antifreeze, insect and fungal deterent), monoecious, reproductive structures are cones

List the four existing groups of gymnosperms. What key characteristics define each group

Horsetails, whisk ferns, and ferns

List the major plant groups found in the monilophyte clade

Monocots- single embryonic cotyledon & eudicots- have two cotyledons

List the names of the two major groups of angiosperms and give the meaning of each name

Liverworts- cells of the sporophyte expand, allowing the stalk to elongate for spore dispersal; reproduce asexually by shedding small clumps of cells called gemmae/ hornworts- have stomata; have symbiotic relationships with cyanobacteria that are able to fix atmospheric nitrogen/ mosses- have hydroids and leptoids; have apical cell division

List the three groups of living nonvascular land plants and discuss the limitations to their success in a terrestrial environment

Xylem- transport water and minerals/ phloem- conducts products of photosynthesis (transport sugar)

Name and provide a function for the two types of vascular tissue in plants

Sperm doesn't swim to egg/have vascular tissue/ secondary growth- provides support for primary growth and facilitates light absorption and seed dispersal/ gametophytes greatly reduced- nutritionally dependent on sporophyte/ all are heterosporous- produces two types of spores/ seeds- aids in protection, dispersal, nourishment, and has extended period of dormancy

Name the 5 main characteristics of seed plants and discuss the significance of each to the success of seed plants on land

Microsporidia- uses harpoon-like polar filaments to inject spore contents into host cell/ chytrids- only fungal with flagellated stage of their life cycle/ zygospore- only 1 diploid cell in entire life/ glomeromycota- entirely asexual, coenocytic, terrestrial, and form arbuscular mycorrhizae/ ascomycota- ascus with 8 sexual spores (ascospores)/ basidiomycota- fruiting structure (basidiomata)

Name the six groups of fungi and provide a key characteristic for each

Thought to be similar to earliest land plants/ lack true leaves, stems, and roots/ short water transported via diffusion/ grow in dense mats in moist habitats/ gametophyte is the dominant generation

Nonvascular plants

Puffballs, bracket, rust, and smut

Provide examples of some common club fungi

One fertilizes the egg (zygote) and one merges with two polar nuclei (endosperm)

State the function of the two sperm carried by the pollen of angiosperms

The flagella is posterior as in animal sperm. Fungi, choanoflagellates, and animals

State the key characteristic of the clade opisthokonts. List the three lineages that exist within this clade

Yeast, truffles, and penicillin/ sexual reproduction involves 2 different mating types moving into a dikaryotic stage before forming a diploid cell population/ zygote undergoes meiosis and then produces an ascus with haploid ascospores; the ascospores germinate and grow into new mycelia/ asexual reproduction in ascomycota involves the production of conidia at the tips of hyphae. Ascus- production of sacs/ ascospores- sexually produced haploids

Summarize the key characteristics and sexual life cycle of the ascomycota. Define the terms ascus and ascoma

Have fruiting structures; septa hyphae/ haploid hyphae of different mating types meet and fuse, forming dikaryotic hyphae, each cell of which contains two nuclei; dikaryotic mycelium produces a basidioma

Summarize the key characteristics and sexual life cycle of the basidiomycota.

Vascular tissues facilitate transport of materials( xylem-conducts water& phloem- conducts sugar)/ lignin impregnated xylem cells( tracheids) provide rigid structural support/ sporophyte is dominant generation/ fertilization(requires water for sperm to swim to egg)

Vascular plants

Seed dispersal and protects seeds until they're mature

What are the two main functions of fruit

Absorptive heterotrophy, chitin in cell walls, most reproduce asexually and sexually, most are multicellular

What synapomorphies distinguish fungi from the animals and flagellated protists