Botany Lab Exam #2 Extended

drupe

- 1-3 seeded with the exocarp and mesocarp fleshy, but the endocarp modified into a hard lignified layer enclosing the seeds - also known as stone fruits - the stone or pit is the lignified endocarp

Rhizoids

- In mosses they are multicellular linear root-like structures that attach the gametophyte to the soil or substrate - unicellular in liverworts and hornworts - primarily used in anchoring the plant to the substrate and have very little absorptive capacity

Mosses (Bryophyte)

- Phylum Bryophyta - Largest group about 10,000 species - in the gaetophytes of some mosses, vascular and conducting tissue is present

`Liverworts (Bryophytes)

- Phylum Marchantiophyta - about 5,200 species - mostly terrestrial in moist areas - a few species are aquatic - most liverwort gametophytes develop directly from spores - a few species produce protonema-like threads from which the gametophyte develops - Two Major Types- 1. Complex thalloid liverworts 2. Leafy Liverworts and Simple Thalloid Liverworts

Psilotopsida

- Two orders 1. Ophioglossales 2. Psilotales

Heteromorphy

- When the gametophyte and sporophyte are different in appearance - both generations are heteromorphic - plants ans a few red an brown algae

Sporopollenin

- a complex polymer of carotenoids and cyclic alcohols that resists decay and drying - most highly chemical resistant biological polymer known - the wall of a spore is impregnated with or almost entirely composed of sporopollenin

Pyrenoid

- a distinct region of the chloroplast that is the center of starch biosynthesis - primitive characteristic - in algae and no other land plant

Amphicarpy

- a few plants produce fruit both above and below ground - in the hog peanut three distinct types of flowers and fruits are produced . The arial stems produce flowers that are either cleistogamous or chasmogamous and each produces a distinct type of legume. The subterranean flowers are cleistogamous and produce a papery fruit with a single large fleshy seed

Marattiopsida

- ancient and tropical group of ferns - a few hundred species still extant

Equisetopsida

- ancient group of ferns - include calamites and horsetails - have jointed stems that occur both above and below ground and scale-like non-photosynthetic leaves - first evolved during the Devonian period - during Devonian period, most horsetails were represented by calamites - these were huge abhorescent forms that could reach heights of about 18 meters tall and had a diameter of up to 45 centimeters - the only extant genus is Equisetumrepresented by 15 species - Equisetum may be the oldest surviving genus of plants on earth

Leptosporangium

- arises from a single superficial (surface) initial cell - After the first cell division of the initial, the outer of he two cells are usually exclusively contributes to formation of the sporangium which is stalked - the inner of the two cells contributes cells to the stalk of the sporangium or plays no role in sporangium formation - have only a single outer layer of cells but have a two-layered tapetum and each spore mother cell only produces 4 spores - produce few spores compared to eusporangia - restricted to the Polypodiopsida

Embryophytes

- bryophytes, ferns and fern allies, progymnosperms, gymnosperms, and angiosperms - all produce a multicellular embryo as a part of their life cycle

Dry Dehiscent Fruits

- capsule

Leptom

- carbohydrtae conducting tissue in mosses

Lycopodiaceae

- club moss family - includes 7 extant genera and about 400 species

Leptoids

- conducting cells in mosses - similar to conducting cells found in Aglaophyton major

Hydroids

- conducting cells in mosses - some have lignified walls

Bryophytes

- consist of three phyla the mosses, liverworts, and hornworts - small plants with leafy or flattened, thalloid type body - widespread in temperate and tropical regions - often the most abundant plant type in the flora north of the Arctic Circle in the tundra, and above the timberline in moutainous regions. Even found in northern Antarctica. - important as primary colonizers of rock and bare soil and areas of post volcanic activity - the gametophytes of most bryopytes lack conductive tissue - In those that do have conducting tissue in their gametophytes, the conductive tissue is not homologous to that of tracheophytes (ferns, gymnosperms, angiosperms) - vascular tissue is not homologous to that of tracheophytes because in bryophytes, it is the gametophyte stage that has the vascular tissue - In all other groups of the land plants the vascular tissue is produced only in the sporophyte stage - the sporophytes of bryopytes lack vascular tissue - exhibit heteromorphic alteration of generations where the gametophyte forms alternate with sporophyte forms and the two are heteromorphic like all other land plants - gametophyte the gametophyte is the dominant generation unlike all other land plants where the sporophyte phase is dominant and the gametophyte phase is reduced - in bryophytes, the sporophyte is small, permanently attached to, and nutritionally dependent upon the maternal gametophyte for survival - can reproduce asexually by fragmentation or through the production of gemmae which are multicellular bodies that give rise to new gametophytes - sexual reproduction involves antheridia and archegonia which are often produced on separate male and female gametophytes - once released from the antheridium, the sperm must swim through water to reach the egg in the archegonium. This means that water is required for fertilization and reproduction in bryophytes and ferns - sperm cells of bryophytes and ferns are flagellated and extend from the side of the cell instead of the end - after fertilization, the zygote remains in the archegonium and is nourished by sugars and amino acids provided by the female gametophyte - the zygote then undergoes mitosis to produce a multicellular embryo - the embryo grows into a mature sporophyte - nutrition and water transport to the sporophyte is via the apoplastic pathway - there is no symplastic connection between the two generations - nutrition transport directly to the sporophyte occurs via the placenta - all cells of the sporophyte are genetically identical to the fertilized egg - most bryophyte spores germinate to form a juvenile development stage known as protonema (proto=first nema=thread) - upon contact with a suitable substrate for growth and development, the protonema develops gametophytes and gametangia -Protonemata are found in mosses and some liverworts, but not in hornworts - thin plant body aids in CO2 uptake - the leaf and stemlike structures on the gametophyte are not homologous to those of higher plants becaue they are produced in the gametophyte phase instead of the sporophyte phase like true leaves roots and stems - some bryophytes have pores in their cuticle for gas exchange - others have stomata in the outer layer of cells that are similar to those of higher plants. The guard cells of the stomata only function for a short period of time to open and close the pore so stomatal function in long-term gas exchange is uncertain - bryophyte gaetophytes have numerous specialized trichomes and structural adaptations for water and nutrient absorption

Multiple Fruits

- consists of an entire inflorescence of separate flowers and ovaries - the ovaries grow together and fuse at maturity forming the fruit

The following terms apply to fruits in the mature condition

- dehiscdent - indehiscent - dry - fleshy

Simple Fruits

- derived from a single ovary - can be simple unicarpellate ovary or compound or multicarpelate ovary

Evolutionary Trends in Sprophytes

- disadvantage to life on land is a lack of water which led to the need for the developement of structures adapted for the uptake and conservation of water and may have led to reduced fertilization rates in early land plants - in land plants, there is an evolutionary trend toward the production of a larger and more complex sporophyte in relation to the gametophyte - one advantage of matrophy and the plant placenta is that they allow for the development of a multicellular and complex sporophyte phase which itself can produce large numbers of spores (more spores from a single fertilization event- remember that the sporophyte develops from a zygote) which may help compensate for lower rates of fertilization that occurred on land - the larger the sporophyte, the more spores that can be produced

Sporocarps

- drought resistant bean-shaped structures used for reproduction - can remain viable outside of water for over 100 years - when hydrated, they produce chains of sori each bearing microsporangia and megasporangia

Indehiscent and fleshy

- drupe - berry - pome - hip

Lycophytes

- eusporangiate, microphyll bearing vascular plants including tree lycophytes many of which are now extinct

Archegonia

- female reproductive structures (the gametophytes of some gymnosperms and those of all angiosperms lack an archegonium)

Placenta

- formed by numerous transfer cells

Dry

- fruit is dry at maturity - has a lower water content - usually dehiscent - non-living

Fleshy

- fruit is soft and fleshy at maturity - has a high water content - indehiscent - animal dispersed - living - the most advanced types of fruits - generally dispersed by vertebrate dispersal agents - when the seeds are fully developed and (the embryos are mature) the tissues of the fruit undergo a series of changes which are governed by the hormone ethylene including: 1. changes in color (from green or yellow to bright yellow, orange, red, or blue 2. A rise in sugar content 3. a softening because of the breakdown of pectic substances

Indehiscent

- fruit wall remaining continual (maintaining its integrity) or closed at maturity - must be opened mechancally or by rotting to expose those seeds

Dehiscent

- fruit wall ruptures to release the seeds at maturity - also known as shattering

One or More Seeds

- fruits function primarily in dispersal and protection during development of the enclosed seeds - the seeds of some plants produce 2 or more different types of fruit have a fleshy appendage or covering known as an aril or sarcotesta (these are not exactly synonymous)

Aggregate fruits

- gynoecium of numerous unfused or separate carpels

Apogamy

- in ferns - is the production of a sporophyte from a gametophyte without egg formation or fertilization - sporophytes are simply produced from vegetative cells of the gametophyte

Apospory

- in ferns - the production of a gametophyte from a sporophyte without meiosis or spore formation - Aposporic gametophytes produce sporophytes directly from unfertilized eggs - these processes result in an agamosporous life cycle and apomictic alteration of generations which allows plants like sterile polyploids to be able to reproduce via spores in addition to typical vegetative asexual reproduction

Agamospermy

- in ferns results in the production of sporophytes from gametophytes without egg formation or fertilization - sporophytes are produced from vegetative cells not gametes - can occur via apogamy or apopory in ferns - in some cases unreduced spores are produced (often larger than normal and spherical in shape) it occurs because of mitotic failure on the last mitotic division from the 2n archesporial cell in the archegonium which produces 2n spore mother cells. Instead, the spore mother cells that are formed after the mitotic failure are 4n. These 4n cells undergo mitotic division producing 2n spores, and these 2n spores then give rise to 2n gametophytes, instead of normal 1n gametophytes - the 2n spore mother cells can also fail to undergo mitosis and instead undergo a single mitotic division which produces unreduced 2n mitospores which can also develop into 2n gametophytes

Ferns and Fern Allies

- in ferns, the sporophyte phase of the life cycle is dominant and has vascular tissues of xylem and phloem - ferns along with gymnosperms and angiosperms have vascular tissues in the sporophyte phase of their lifecycle and because of this are often referred to as tracheophytes - in ferns and fern allies the spores develop in sporangia - the gametophytes of diploid species of homosporous ferns are functionally unisexual (heterothallic) - the sporophytes of most ferns are heterozygous which demonstrated that they did not arise from self-fertilization (sperm and egg from a single gametophyte) This means sperm and egg from two separate gametophytes are required for fertility. - usually on any given gametophyte the antheridia and archegonia mature at different times - can reproduce via agamospermy

Fruit Categories and Types

- indehiscent and fleshy - dry dehiscent - indehiscent dry fruits - Compund or complex fruits

Antheridia

- male reproductive structures (absent in gametophytes of seed plants

Accessory Tissue / Non-Ovarian Tissue

- may or may not be present depending on fruit type - fruits with this tissue are knwon as accessory fruits - sometimes fruits with non-ovarian tissues are known as false fruits

Euphyllophytes

- megaphyll-bearing plants with or without mulit-flagellate sperm cells - include phylum monilophyta, tha calamites or giant horsetails (now extinct), and all seed plants

Sporic Meiosis

- meiosis results in spores instead of gametes (meiospores) - meiospores are haploid or higher ploidy level cells that can divide mitotically to produce a multicellular organism (gametophyte) - this gametophyte produces gametes - The spore producing organism or stage of the cycle is known as the sporophyte (spore producing) - the gametophyte is always haploid if the sporophyte is diploid or has one-half the number of chromosomes as the sporophyte, if the sporophyte is polyploid - in sporic meiosis multicellular gametophyte organisms alternate with multicellular diploid or polyploid forms of the same organism - one form is always completely dependent and parasitic on the other - sporic meiosis occurs in all plants and in some green, red, and brown algae - in plants and a few red and brown algae the gametophyte and the sporophyte are different in appearance (Heteromorphy) - In sporic meiosis of flowering plants the gametophyte is small highly specialized and consists of only a few cells - the microgametophyte consists of only 3 cells - megagametophyte has 7 cells (some species of angiosperms have more) - the gametophytes of seed plants are completely parasitic on the sporophyte for survival - the sporophyte consists of millions of cells and is not dependent upon the gametophyte for survival

Microphylls

- more ancient than megaphylls - probably originated as enations - only a few groups probably posses them like the Lycopodiales.

Hesperidium

- multisegmented berry with a tough leathery rind that is impregnated with oil glands, and with the endocarp tissue modified into numerous juice sacs

Berry

- numerous types - in general have a fleshy pericarp and multiseeded fruit 3 types 1. pepo 2. hesperidium 3. calabash

Homospory

- occurs in the psilophytes (whick ferns), sphenophytes (horsetails), the lycophytes (in part club mosses), and nearly all pteridophytes (true ferns) - have the potential upon germination to produce bisexual gametophytes which will produce both antheridia and archegonia on the same gametophyte or plant body - the gametophytes are independent of the sporophyte for survival some are autotrophic and photosynthetic (sphenophytes and pteridophytes) and others are saprophytic and heterotrophic or dependent upon endomycorrhizal fungal symbionts for nutrient and water uptake

Compound or Multicarpellate ovary

- ovary consists of 2 or more carpels where the individual carpels are fused

Simple Unicarpellate

- ovary consists of one carpel

Lycopodiophyta

- phylum that includes the club mosses, quillworts, and resurrection plants which constitute 3 families, 10 to 15 extant genera, and about 1,000 species - the lycophytes probably first evolved during the Devonian period of the paleozoic era - some ancient lycophytes were arborescent (tree-like) - arboescent lycophytes were some of the dominant plants during the Carboniferous period - Major Families 1. Lycopodiaceae 2. Selaginellaceae 3. Isoetaceae - members of selaginellaceae and isotaceae are heterosporous

Homosporous

- plants that produce only one type of spore - early vascular plants produced only one type of spore from meiosis

Megaspore

- produced in megasporangia - give rise to female gametophyte or megagametophyte

Microspore

- produced in microsporangia - give rise to male gametophytes or microgametophyte

Aglaophyton major

- protracheophyte - may have been an intermediate between the bryophytes and tracheophytes

Ophioglossales

- rattlesnake or grape ferns, adder's tongue ferns

Extant Phyla of ferns and fern allies

- recent phylogenetic evidence places ferns and fern allies into two groups 1. Monilophyta 2. Lycopodiophyta

Seed Plants

- reproduction in seed plants is overall very similar with a few notable exceptions 1. the megagametophytes of some gymnosperms have archegonia, whereas the megagametophytes of angiosperms along with some gnetophyte gymnosperms lack archegonia 2. the microsporophylls and megasporophylls of angiosperms are modified/specialized to form stamens and carpels respectively 3. the ovules of gymnosperms are not enclosed by the megasporophyll whereas the ovules of angiosperms are enclosed within the modified megasporophyll 4. the nutritive tissue of the seeds of gymnosperms is comprised of a portion of the megagametophyte whereas the principal nutritive tissue in angiosperm seeds is a specialized tissue known as the endoderm that is produced by the fertilization of the binucleate central cell with a sperm cell and subsequent mitosis (perisperm may also be present as a nutritive tissue in the seeds of some angiosperm) 5. the microgametophytes and megagametophytes of agiosperms are even more reduced and specialized than those of gymnosperms

Selaginellacea

- resurrection plant family or selaginella plant family - one extant genus selaginella with about 700 species

Pome

- seeds are enclosed within the cartilaginous or papery ovary whereas the majority f the fleshy portion of the fruit is derived from non-ovarian tissue (in this case such as the hypanthum or floral tube) - derived from inferior or partially inferior ovaries

Calabash

- similar to the pepo but derived from a superior ovary

Enations

- small outgrowths of the stem

Monocarpic

- some plants flower and fruit only once in their lifetime and then die - this is a type of reproductive strategy

Heterocarpy

- some plants produce two or more different types of fruits - ex produces dehiscent and indehiscent fruits or producing fruits that are dispersed by different dispersaal agents

Gametic Meiosis

- some zygotes began to divide mitotically instead of meiotically. This advancement happened independently in numerous types of organisms. - the mitotic division process would now allow for the formation of multicellular organisms that are comprised of diploid cells - later these diploid cells would have a delayed meiosis resulting in gametes - remember these gametes are haploid. When the gametes fuse (syngamy) this immediately restores the diploid state - In gametic meiosis the gametes are the only haploid portion of the life cycle - animals, water molds, and some green and brown algae undergo gametic meiosis

Lignophytes

- sometimes phylum progemnospermophyta (the progymnosperms and seed plants gymnosperms and angiosperms are collectively referred to as lignophytes because they all possess taxa that produce secondary phyla or wood)

Transfer Cells

- specialized parenchyma cells with invaginated and highly branched cell wall ingrowths - these ingrowths increase the surface area of the plasmalemma allowing for more enzymes and proteins that are involved with the transport of substances - the proteins and enzymes are required because the transport of many substances is accomplished through energy dependent active transport - similar transfer cells occur in the gametophyte/sporophyte interface of higher plants

Sporangia

- spore-bearing sacs aggregated into clusters known as sori - sori usually occur on the undersurface of fronds (palm leaves)

Vegetative Reproduction of Sporophytes and Gametophytes

- sporophytes and gametophytes of many species can reproduce vegetatively - sporophytes can reproduce vegetatively through rhizome production (new rhizome segments can produce new plants) stem segments and fragments, or bulbets and tubers - vegetative reproduction in sporophytes is especially important for sterile hybrid ferns that cannot reproduce sexually - gametophytes of some species of ferns can also reproduce vegetatively - many gametophytes if old or under poor conditions will produce multicellular gemmae from their margins - these gemmae will develop into new gaetophytes after they are detached from the parents gametophyte - in some fern species the gametophytes can form extensive vegetative colonies and in some species only the gametophyte phase of the life-cycle is known

Zygotic Meiosis

- the 1st Eukaryotes were probably haploid and asexual with respect to reproduction - the evolution of sexual reproduction made polyploidy and diploidy possible - initially two haploid cells combined to form a diploid zygote - zygote is divided into haploid cells by meiosisterm-9 - some algaes and fungi are haploid with the zygotic the only diploid portion of the life cycle

Venter

- the enlarged basal portion of the archegonium which contains the egg enlarges and becomes the calyptra

Aril or Sarcotesta

- the fleshy appendage or covering on the seeds of some plants - not exactly the same thing - often brightly colored and used to attract dispersal agents

Calyptra

- the hood or cap that partially covers the capsule in some species of mosses it is derived from the extended archegonial wall

Eusporangium

- the parent cells/initials are located at the surface of the tissue from which the sporangium is produced - the wall of the sporangium consists of several cell layers that are derived from the outer layer of the first two wall layers produced from the initials during early development - the inner layer gives rise to sporogenous cells that ultimately produce the spore mother cells - the innermost wall layer of the sporangium is referred to as the tapetum which probably provides nourishment to the developing spores - eusporangia produce large numbers of spores and are characteristic of all vascular plants with the exception of leptosporangiate ferns

Heterospory

- the production of two different types of spores in two different types of sporangia - some lycophytes, pteridophytes (true ferns), and all seed plants are heterosporous - has developed independently in many groups of unrelated plants - the earliest known record of heterospory is about 370 million years ago during the Devonian period - produce two types of spores in two different types of sporangia ( microspores in microsporangia and megaspores in megasporangia) - these two types of spores are separated by function and sometimes size - both are unisexual and much smaller and specialized than those of homosporous plants - dependent upon the sporophyte phase for survival and development

Evolutionary Trends in Gametophytes

- there is a general trend towards reduction in the size and complexity of the gametophyte in advanced groups of plants where the smallest and least complex gametophytes are found in the highly advanced angiosperms (Phylum Anthophyta) - there is also an increase in specialization of the gametophyte in land plants where the most specialized and reduced gametophytes occur in the seed plants where the most specialized and reduced seed plants occur in phylum anthophyta - the gametophytes of seed plants are contained within and parasitic upon the sporophyte phase - their only role is to produce gametes (and in the case of the female gametophyte also the nutritive tissue for the seed)

Extinct fern-type vascular plants

- three phyla of early vascular were the Rhyniophyta, Zosterophyllophyta, and Trimerophtophyta - these were vascular plants that were simple in structure - they produced spores only (were not seed plants) - the progymnospermophyta were ferns that underwent secondary growth - many ferns only undergo primary growth

Fruits

- traditional view- ripened or mature ovary - Modern view- fruit wall, accessory tissues (if present), and any seeds in the case - In the case of parthenocarpy, fruit only -Three Major Categories 1. Simple Fruits 2. Aggregate fruits 3. Multiple fruits

Polypodiopsida

- true ferns - leptosporangiate and mostly homosporous ferns - most fern species about (10,500+) - ferns first came to prominence during the Carboniferous period - third largest group of vascular plants in number of species behind bryophytes and anthophyta - occur in virtually all environments around the world - there are over 12,000 species of vascular plants in total - three quarters of the species are found in the tropics about one third of them are epiphytic - about 380 species in North America - epiphytic, terrestrial, or aquatic in life habit - most are herbaceous, but some are vining or arborescent in habit - all species of ferns regardless of form only undergo primary growth - some of the largest tree ferns reach heights of 24 meters with trunks up to 30 centimeters in diameter (most of this thickness is comprised of a fibrous mantle of roots - The orders Marsileales and Salviniales are heterosporous sporocarp producing ferns with 3 main families 1. Marsieaceae- water clover family 2. Salviniasceae- water sprangle family or floating fern family 3. Azollaceae- mosquito fern family - all species in these families are heterosporous and produce sporocarps

Tracheophytes

- true vascular plants - sporophyte is dominant - gametophyte is very reduced and free-living (ferns and fern allies), or further reduced and cmpletely parasitic on the sporophyte (seed plants) - subdivided into the lycophytes, Euphyllophytes, and Lignophytes

Monilophyta

- two types of sporangia are present on monilophyte ferns - the difference is in the structure and method of development of the sporangium and the number of spores produced - classified as either eusporangiate or leptosporangiate depending on the type of sporangia produced - 4 principal classes 1. Psilotopsida 2. Marattiopsida 3. Equisetopsida 4. Polypodiopsida

Megaphylls

- typical leaves and their modifications - more derived evolutionarily than microphylls - found in most ferns and all seed plants (Euphyllophytes (Monilophyta and all seed plants))

Hadrom

- water conducting tissues in mosses

Isomorphy

- when the gaametophyte and sporophyte are similar in form - the case with most algae that undergo sporic meiosis

Exosporic Development

- when the gametophytes develop outside the spore wall in homosporous plants

Endosporic Development

- when the gametophytes develop within the spore wall in heterosporic plants

Matrophy

- when the zygote remains in the archegonium after fertilization and is nourished by the maternal gametophyte

Psilotales

- whisk ferns - represented by two extant genera 1. Psilotum- whisk fern lacks roots and leaves majority of its body is comprised of above and below ground stems the rhizomes take place of the root system mycorrhizal fungi probably assist in water and nutrient uptake possibly one of the most ancient tracheophyte plants known occasionally terrestrial 2. Tmesipteris - species of both genera are epiphytes (Psilotum is occasionally terrestrial)

Hornworts

-Phylum Anthocerophyta - about 300 species - Anthocerus is the most common genus - hornworts and liverworts are dichotomously branched and thalloid often appear leafy - the chloroplasts of hornworts, along with those of algae, possess a pyrenoid, which is a distinct region of the chloroplast that is the center of starch biosynthesis - the chloroplasts of other bryophytes and tracheophytes lack a pyrenoid

Isoetaceae

-quillwort family - one extant genus Isoetes with about 150 species - Isoetes is possibly the closest living relative to the tree lycophytes of the Carboniferous period

Capsule

-the sporangium of a bryophyte

Three Phyla of Bryophytes

1. Liverworts (Phylum Marchantiophyta) 2. Hornworts (Phylum Anthocerotophyta) 3. Mosses (Phylum Bryophyta)

Characteristics unique to land plants

1. The presence of multicellular male and female gametangia 2. retention of the zygote and subsequent developing embryo (young sporophyte) within the archegonium or embryo sac (female gametophyte) 3. presence of a multicellular diploid or polyploid sporophyte 4. multicellular sporangia consisting of a sterile jacket layer and internal spore-producing tissue (sporogenous) 5. spores with walls containing sporopollenin 6. tissues produced by an apical meristem 7. multicellular embryo in life cycle *characteristics 1-6 are adaptations to life on land where water is limited

Parts of the fruit

1. The three layers of the fruit wall or pericarp - exocarp or epicarp- outer layer - mesocarp- middle layer - endocarp- inner layer 2. Accessory Tissue or Non-Ovarian Tissue 3. One or more seeds

Leaves can be divided into two main categories

1. megaphylls 2. microphylls

Prothalli

Another name for gametophyte

Sterile Jacket Layer

Both Antheridia and Archegonia have an external, protective layer of cells known as the sterile jacket layer

Hip

an aggregation of achenes surrounded by a fleshy cuplike receptacle or hypanthium

Charophytes

group of green algae believed to be the most closely related taxonomic group to the land plants

Epiphytic

grow on branches of tall plants, tropical rain forest

Pepo

has a hard tough rind and is derived from an inferior ovary