Chapter 29 of Cambell's Biology textbook , ninth edition
The chapter is on the first half of plant diversity and how plants colonized the land.
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| 675291751 | Closest relatives to Land Plants | Charophytes- photosynthetic protist- a type of algae Ex: Chara & Coleochaete orbicularis | 0 | |
| 675291752 | 4 synapomorphies of land plants & charophytes | 1.) Rings of cellulose-synthesizing proteins 2.) Peroxisome enzymes 3.) Structures of flagellated sperm 4.) Formation of a phragmoplast | 1 | |
| 675291753 | Rings of cellulose-synthesizing proteins | Both my rings of proteins in the plasma membrane that synthesize cellulose microfibrils of the cell wall (non charophyte algae have linear proteins) | 2 | |
| 675291754 | Peroxisome enzymes | Peroxisomes of both types of organisms contain enzymes to help minimize the loss of organic products results from photorespiration | 3 | |
| 675291755 | Structure of flagellated sperm | both have sperm with similar structures | 4 | |
| 675291756 | Formation of a phragmoplast | Phragmoplast- a group of microtubules that forms between daughter nuceli of a dividing cell. A cell plate then develops in the middle of the phragmoplast--> cell plate gives rise to new wall that seperates daughter cells | 5 | |
| 675346044 | Sporopollenin | found in charophytes - prevents exposed zygotes from drying out ; may have helped evolutionary transition to land | 6 | |
| 675346045 | 5 Synapomorphies found ONLY in land plants | 1.) Alternation of Generations ; 2.) Muticellular, Dependent Embryos ; 3.) Walled spores produced in sporangia; 4.) Multicellular Gametangia; 5.) Apical meristems - all are derived traits of land plants | 7 | |
| 675346046 | 1.) Alternation of Generations | life cycle of land plants alternates between gametophytes and sporophytes. Each generation gives rise to the other. - half the cycle is haploid (n) and half is diploid (2n) | 8 | |
| 675346047 | 5 steps of Alternation of Generation Life Cycle | 1.) The gametophyte produces haploid gametes (n) by mitosis 2.) 2 gametes unite(fertilization) to form a diploid (2n) zygote 3.) Zygote develops into multicellular diploid (2n) sporophyte 4.) Sporophyte produces haploid (n) spores by meiosis 5.) Spores develop into haploid gametophytes by mitosis- cycle begins again | 9 | |
| 675346048 | Gametophyte | - multicellular haploid that is produces, by mitosis, haploid gametes- egss & sperm- that fuse during fertilization, forming diploid zygotes | 10 | |
| 675346049 | Sporophyte | - multicellular diploid that is produced by mitotic division of the zygote Ex: in a fern, this is the large plant that we recognize | 11 | |
| 675346050 | 2.) Multicellular, Dependent Embryos | -these embryos develop from zygotes retained in the female gametophyte. The parent tissue provides the embryo with nutrients such as sugars and a.a.'s - embryo has specialized placental transfer cells - this is analogous to the embryo-mother interface of placental mammals = hence land plants are called embryophytes | 12 | |
| 675346051 | Placental transfer cells | -sometimes present in adjacent maternal tissue as well - enhance the transfer of nutrients from parent to embryo through ingrowths of the wall surface | 13 | |
| 675346052 | 3.) Walled Spores Produced in Sporangia | - On the sporophyte, the sporangia produce the spores - Within the sporangia, diploid cells produce sporocytes, or spore mother cells--> these will form haploid spores via meiosis - sporangium- protects developing spores until they are released into the air -spores also have sporopollenin that make spore walls tough and resistant to drying out | 14 | |
| 675346053 | 4.) Multicellular Gametangia | -gametes are produced inside here. - there are male and female gametangia | 15 | |
| 675346054 | Archegonia | female gametangia - produces an egg retain the bulbous part of the organ -each egg is fertilized inside the the archegonium where the zygote becomes an embryo | 16 | |
| 675346055 | Antheridia | male gametangia - produces sperm and releases them into the environment -sperm have flagella that swim to the egg in droplets of water | 17 | |
| 675346056 | 5.) Apical meristems | -Roots and shoots of terrestrial plants elongate to increase exposure to resources (i.e. sunlight, water, minerals etc.) - apical meristems are regions of cell division at the tips of roots and shoots - growth in length of a plant's life is sustained by apical meristems | 18 | |
| 675346057 | Cuticle | waxy covering on leaves to prevent dessication and water loss & protect against some microbial attack | 19 | |
| 675346058 | Origin of Land Plants | 475 million years ago | 20 | |
| 675346059 | Origin of Vascular plants | 425 million years ago | 21 | |
| 675346060 | Origin of extant seed plants | 305 millions years ago | 22 | |
| 675346061 | Vascular tissue in plants | cell joined into tubes that transport water and nutrients thru out the plant body - plants that have this = vascular plants | 23 | |
| 675346062 | Non-vascular plants | lack vascular tissue commonly called bryophytes | 24 | |
| 675346063 | 3 types of Bryophytes | liverworts, mosses, and hornworts - in bryophytes, haploid gametophytes are the dominant stage in the life cycle | 25 | |
| 675346064 | Two types of Seedless Vascular plants | Lycophytes (club mosses and their relatives) and pterophytes (ferns and their relatives) | 26 | |
| 675346065 | Grade | collection of organisms that share a key biological feature - do not necessarily share the same ancestry Ex: Seedless vascular plants- are not part of clade, are actually paraphyletic | 27 | |
| 675346066 | Seed | embryo packaged with a supply of nutrients inside a protective coat | 28 | |
| 675346067 | Two types of seed plants | gymnosperms and angiosperms | 29 | |
| 675346068 | Gymnosperms | have "naked" seeds - seeds are not enclosed in chambers | 30 | |
| 675346069 | Angiosperms | -huge clade of flowering plants - seeds develop inside chambers called ovaries, which mature into fruits -90% of living plants are angiosperms | 31 | |
| 675346070 | 3 Phylum of Bryophytes (non-vascular plants) | 1.) Hepatophyta - liverworts ; ex: Marchantia 2.) Bryophyta- mosses ; ex: "peat moss"- a.k.a Sphagnum 3.) Anthocerophyta- hornworts- their sporophytes lack a seta and only have a sporangium | 32 | |
| 675404987 | Bryophyte gametophytes | - the haploid gametophytes dominate their life cycle - germinating spores grow into gametophytes | 33 | |
| 675404988 | Protonema | - developed from germinating moss spores - one-cell thick filaments that has a large surface area for absorbing mineral & water absorbtion - in favorable conditions this protonema will produce a "bud" that has apical meristem that will generate a gametophore | 34 | |
| 675404989 | Gametophore | gamete-producing structure on the "bud" - gametophore together with a protonema make up a gametophyte | 35 | |
| 675404990 | Why are bryophytes typically smaller than other plantss? | their body parts are too thing to support a tall plant and they lack vascular tissue so do not have the ability to transport nutrients and water over long distances | 36 | |
| 675404991 | Rhizoids | anchors the gametophytes - are long and tubular in liverworts & hornworts -filament of cells in mosses - similar to roots but do absorb water or minerals | 37 | |
| 675404992 | Bryophyte Sporophytes | - are the smallest of all extant plant groups - consists of a foot, a seta, and sporangium (a.k.a capsule) - most seta becomes elongate to enhance seed dispersal by elevating the sporangium - pores in them called stomata- water evaporates from this (only present in mosses and hornworts) | 38 | |
| 675404993 | Life cycle of a moss | - majority is haploid 1.) Haploid (n) spores develop into threadlike protonemata 2.) Protonemata produces "buds" that divide by mitosis and grow into gametophores --> which forms the male or female gametophytes (n) 3.) Gametophytes form archegonium and antheridia 4.) Sperm from antheridia swim through a film of moisture to reach the egg at the achegonium (fertilization) | 39 | |
| 675404994 | Life cycle of a moss continued | 5.) Zygote (2n) forms inside archegonium and develops into a sporophyte embryo 6.) Sporophyte grows a long stalk (seta) that emerges from the archegonium 7.) The sporophyte remains attached by its foot and nutritionally dependent on the gametophyte 8.) Meiosis occurs and haploid (n) spores develop in the capsule (or sporangium) until it matures and then the spores are released and cycle repeats | 40 | |
| 675416491 | Seedless Vascular Plants | - had well developed vascular systems by the Devonian era - has flagellated sperm that must swim through water to reach the egg, like bryophytes | 41 | |
| 675416492 | Traits of ancestral vascular plants | - branched sporophytes that were not dependent on gametophytes for nutrition - made it possible to have more complex bodies with multiple sporangia - lacked roots ex: Aglaophyton major- an ancient relative or modern vascular plants | 42 | |
| 675416493 | Traits in living vascular plants | 1.) life cycles with dominant sporophytes 2.) transport in vascular tissue 3.) well-developed roots and leaves, including spore-bearing leaves called sporophylls | 43 | |
| 675416494 | Life Cycle of a Fern | 1.) Sporangia release spores (n). Ferns produce a single type of spore that develops into a bisexual photosynthetic gameteophyte 2.) each gametophyte develops both a sperm-producing antheridium and and egg-producing archegoniums 3.) Flagellated- sperm swim to eggs in archegonia (fertilization) | 44 | |
| 675416495 | Life Cycle of a Fern part 2 | 4.) A zygote (2n) develops into a new sporophyte. The young plant grows out from an archegonium of its parent, the gametophyte 5.) on underside of mature sporophytes' reproductive leaves are spots called sori- cluster of sporangia 6.) sporangia undergoes meiosis and will release its haploid spores(n)- cycle begins again. | 45 | |
| 675416496 | Two types of vascular tissue | xylem & phloem | 46 | |
| 675416497 | Xylem | -moves water and minerals through the vascular tissue - in most plants this includes tracheids- tube shaped cells that carry water and minerals up from the roots | 47 | |
| 675416498 | Phloem | - tubes that distribute sugars, a.a.'s, and other organic products | 48 | |
| 675416499 | Roots | -absorb water and nutrients from the soil - help to anchor vascular plants | 49 | |
| 675428140 | Leaves | increase the SA of the plant body and act as the primary photosynthetic organ of vascular plants - classified as either micro- or mega- phylls | 50 | |
| 675428141 | Microphylls | -only lycophytes have these - small spine-shaped leaves supported by a single strand of vascular tissue - may have evolved from sporangia located on the side of the stem | 51 | |
| 675428142 | Megaphylls | - leaves with highly branched vascular system - may have evolved by the fusion of branched stems | 52 | |
| 675428143 | Sporophylls | modified leaves that bear sporangia - vary in structure | 53 | |
| 675428144 | Sori | culsters of sporangia produced by fern sporophylls | 54 | |
| 675428145 | Strobili | cone-like structures formed from lychophyte and gymnosperm sporophylls | 55 | |
| 675428146 | Homosporous | one type of sporangium that produces one type of spore --> forms a bisexual gametoophyte, like in ferns | 56 | |
| 675428147 | Heterosporous | has two types of sporangia and produce two kinds of spores: megaspores or microspores | 57 | |
| 675428148 | Megaspores | - produced by megasporangia on megasporophylls - develop into female gametophytes | 58 | |
| 675428149 | Microspores | - produced by microsporangia on microsporophylls - develop into male gametophytes | 59 | |
| 675635451 | 2 Clades of Seedless Vascular Plants | Lycophytes (Phylum Lycophyta) & Pterophytes (Phylum Pterophyta) | 60 | |
| 675635452 | Lycophytes | Club mosses, Spike Mosses and Quillworts - most ancient group of vascular plants - were prevalent during Carboniferous period (359-299 mya ; had large lycophyte trees 40m tall near swamps but died out when Earth's climate dried out | 61 | |
| 675635453 | Pterophytes | Ferns, Horsetails, and Whisk Ferns - ferns radiated outward from the Devonian and joined lycophyte trees and horsetails in the Carboniferous period - ferns are the most widespread seedless vascular plant | 62 | |
| 675635454 | Shared traits Between Pterophytes and seed plants | - pterophytes are more closely related to see plants than lycophytes -both have overtopping growth, megaphyll leaves, and branching roots at various points along existing root - in contrast, lycophyte roots only branch at tip of the root forming a Y shape | 63 | |
| 675635455 | Lycophyte Characteristics | - many grow on tropical trees as epiphytes ; others on forest floors - spike/club mosses have strobili = cluster of sporophylls - club mosses are homosporous - spike mosses and quill worts are heterosporous - club mosses release spores in cloud= once used to ignite and create a flash in old photography Ex: Lycopodium | 64 | |
| 675635456 | Epiphytes | plants that use other plants as a substrate but are not parasites | 65 | |
| 675635457 | Ferns | - have megaphylls - sporophytes have horizontal stems that give rise to fronds, divided into leaflets - most are homosporous - most have sporopytes with stalked sporangia to catapult spores several meters | 66 | |
| 675635458 | Horsetails | ex: Equistem arvense - historically used as "scouring rushes" due to bristly appearance - homosporous, have cones that release spores that give rise to bisexual gametophytes -also called arthrophytes "Jointed plants" b/c the stems have joints | 67 | |
| 675635459 | Whisk Ferns | -sporophytes have dichotymously branching stems, but no roots - each yellow knob on a stem is 3 fused sporangium -homosporous, with spores giving rise to bisexual gametophytes Ex:Psilotum nudum | 68 | |
| 675635460 | How did Seedless Vascular Plants affect life on Earth during the Devonian/ Carboniferous periods? | - plants accelerated rate of photosynthesis -> increasing removal of CO2 from atmosphere (CO2 levels dropped 5 fold during this time) --> this caused global cooling and glacier formation | 69 |
