Chapter 23 Flashcards
Alternation of Generations
The regular alternation of mode of reproduction in the life cycle of an organism, such as the alternation between diploid (sporophyte) CO2 in a two-step series that also converts NADH into CO2 and NAD^+
Sporophyte
The diploid generation produces spores and is called Phyte: Plant, hence sporophyte.
Gametophyte
The haploid generation produces gametes by mitosis and is called a gamete producing plant.
Cuticle
The outer layer of plants and some animals, which helps prevent desiccation by slowing water loss. Present in all Bryophytes.
Poikilohydric
Having little control over internal water content. Poikilo: variable, hydric: relating to water.
Stomata
The opening between a pair of guard cells in the epidermis of a plant leaf or stem, through which gases and water vapour pass. Present in mosses and hornworts (not liverworts)
Vascular Tissue
In plants, tissue that transports water and nutrients or the products of photosynthesis through the plant body
Nonvascular Plants
Some plants such as mosses lack vascular tissues, do still have tissues that conduct water and sugars through their bodies. These tissues are not the same as xylem and phloem, so they are not called vascular tissues.
Apical Meristems
A region of unspecialized dividing cells at the shoot tips and root tips of a plant.
Roots
Anchoring structures that also absorb water and nutrients.
Root systems
An underground (or submerged) network of roots with a large surface area that favours the rapid uptake of soil water and dissolved mineral ions.
Shoot systems
Have stems and leaves that arise from apical meristems and that function in the absorption of light energy and CO2.
Homosporous
Producing only one type of spore
Heterosporous
Producing two types of spores, “male” microspores and “female” megaspores.
Microspores
A plant spore from which a male gametophyte develops; usually smaller than a megaspore
Megaspores
A plant spore that develops into a female gametophyte; usually larger than a microspore
Bryophytes
A general term for plants (such as mosses) that lack internal transport vessels. Bryon: moss. Bryophyte gametophytes produce gametes in a protective organ called a gametangium.
Rhizoids
A modified hypha that anchors a fungus to its substrate and absorbs moisture.
Archegonia
The flask-shaped structure in which bryophyte eggs form.
Antheridia
In plants, a structure in which sperm are produced
Bryophyta
The phylum of nonvascular plants, including mosses and their relatives
Protonema
The structure that arises when a liverwort or moss spore germinates and eventually gives rise to a mature gametophyte
Hepatophyte
The phylum that includes liverworts and their bryophyte relatives
Anthrocerophyta
The phylum comprising hornworts
Rhizomes
A horizontal, modified stem that can penetrate a substrate and anchor the plant
Lycophyta
The plant phylum that includes club mosses and their close relatives
Pterophyta
The plant phylum of ferns and their close relatives
Sporophylls
A specialized leaf that bears sporangia (spore-producing structures). Phyll: leaf, thus sporophyll: spore-bearing leaf.
Cone
(1) in cone-bearing plants, a cluster of sporophylls. Also called a strobilus
Sorus
A cluster of sporangia on the underside of a fern frond; reproductive spores arise by meiosis inside each sporangium.
Endosporous
Pattern of development in some plants (e.g., seed plants) in which the gametophyte develops inside the spore wall.
Gymnosperms
A seed plant that produces “naked” seeds not enclosed in an ovary.
Pollen grain
The male gametophyte of a seed plant
Pollination
The transfer of pollen to a flower’s reproductive parts by air currents or on the bodies of animal polinators.
Pollen tube
A tube that grows from a germinating pollen grain through the tissues of a carpel and carries the sperm cells to the ovary.
Coniferophyta
The major phylum of cone-bearing gymnosperms, most of which are substantial trees; including pines, firs, and other conifers.
Cycadophyta
A phylum of palmlike gymnosperms known as cycads, the pollen-bearing and seed-bearing cones (strobili) occur on separate plants.
Ginkgophyta
A plant phylum with a single living species, the ginkgo tree
Angiosperms
A flowering plant, its egg-containing ovules mature into seeds within protected chambers called ovaries.
Flower
The reproductive structure of angiosperms, consisting of floral parts grouped on a stem; the structure in which seeds dwell.
Fruit
A mature ovary, often with accessory parts, from a flower.
Anthophyta
The phylum comprising flowering plants
Monocot
A plant belonging to the monocotyledones, one of the two major classes of angiosperms; monocot embryos have a single seed leaf (cotyledon) and pollen grains with a single groove.
Eudicot
A plant belonging to the eudicotyledones, one of the two major classes of angiosperms; their embryos generally have two seed leaves (cotyledons) and their pollen grains have three grooves.
