Environmental Botany- Vocabulary terms. Bryophytes, Gymnosperms, Angiosperms, and Tracheophytes

Bryophytes

• emerged during the Ordovician-Silurian periods,

• first land plants,

• has adaptations to mildly protect from dessication.

• Haploid Gametophyte dominant stage of life.

Vascular tissue

• an evolved trait that transports water, nutrients, and aids in photosynthetic processes

• was not present in the earliest land plants.

Tracheophytes (Vascular plants)

innovations include:

• Vascular tissues- transport and support

• apical meristems- mitosis, growth of plant

• differentiated organs- roots, stems, and leaves.

• diploid sporophyte dominant and independent stage of life.

Most dominant expansion period was during the Carboniferous period.

Archedonia

produces eggs in gamete production

Antheridia

produces sperm cells in gamete production.

Heterospory

producing two different kinds of seeds originating in the same plant.

• large megaspore (female)

• small microspore (male)

Sporophyte generation

• matured sporophyte produces sporangia

• inside of sporangia, haploid spores produced due to meiosis

Gametophyte generation

• spores grow into gametophytes with antheridia and archegonia.

• sperm must swim to egg to complete fertilization

Meristematic tissue

• undifferentiated cells

• divides by mitosis

Permanent tissue (non-meristematic)

• specialized cells

• no longer divides

dermal tissue

• outer layer of plant

• protects from desiccation

• allows for gas exchange through stomata

vascular tissue

• tissue supports transport and structure

• contains xylem and phloem

ground tissue

• fills spaces between the other two types of tissue

• three distinct types of this tissue includes: Parenchyma, Collenchyma, abd Sclerenchyma

Microphylls

• small leaves with single veins

• developed in early plants

Megaphylls

• larger, broader leaves with complex veins

• evolves independently later, sign of convergent evolution

sporophylls

• either type of leaf that bears sporangia

xylem system

• moves water and minerals from roots to leaves

• most water exits plant system through leaves by transpiration.

• contains long tubular cells, functional when dead. tracheid

• No cytoplasm or organelles

• water potentials (pressure) drive movement from bottom of plant to top.

Phloem system

• moves sugar from sources to sinks. (production/source, to being used)

• long tubular cells, has sieves

• living cells but without organelles

• each sieve cell has a companion cell to assist with metabolic activity.

• translocation: moving products of photosynthesis (like sugars)

Transpiration/Evapotranspiration

• occurs with open stomata

• process of evaporation from leaves

• guard cells control whether or not stomata opens to facilitate gas exchange.

gymnosperms

• also known as vascular plants

• first seeded plant

• transitioned toward this plant during the late-Devonian period

• natural selection supported more water independent and fire-resistant plants.

• transition from spores to seeds, protecting embryo, able to be dormant until climate is favorable.

pollen cones

• considered the sporophyte home for gametophytes in gymnosperms.

• an arrangement of microsporophylls.

• produces male gametophytes

seed (ovulate) cones

• composed of megasporophylls (strobilus)

• produces female gametophytes (ovules)

• protects embryos and allows for dormancy.

Phylum Cycadophyta

• gymnosperm phyla

• Mesozoic period (“Age of ____”)

• contains a large, prominent cone

• most popular as ornamental (decorative) plants

• ~100 species exist today

Phylum Ginkgophyta

• gymnosperm phyla

• only one living species: ______ biloba

• dioecious (has separate male and female trees)

• air pollution tolerant

• ornamental tree

Phylum Gnetophyta

• a gymnosperm phyla

• three genera: Ephedra, Gnetum, Welwitschia

• habitats include rainforests, or deserts

Phylum Coniferophyta

• largest gymnosperm phyla

• more efficient vascular system

• contains trees like sequoias, redwoods, wollemi pines and bristlecones.

• thick waxy cuticle, allowing survival in dry, nutrient-poor climates.

lateral meristems- primary growth

increases length of stem or roots.

lateral meristems- secondary growth

increases width or girth of stem or roots.

vascular cambium

• produced during the primary growth in woody plants

• provides plant with structural support and increased height

• protected by secondary growth layer.

cork cambium

• the protective outer bar

• responsible for secondary growth in woody plants

• protects first growth structure in the center

springwood

• the lighter ring during a year of growth

• rapid growth occurs, with large, thin-walled cells

summerwood

• the darker ring during a year of growth

• slow growth, dense, thick-celled walls

sap wood

• the functional, living part of the secondary growth.

Angiosperm

• develops at the end of the Cenozoic Era

• coevolves with its polinators

• dominant stage in life cycle is diploid sporophyte

• adapts through seed dispersal and improved vascular function

sepal

• one of the four floral organs

• located in the Calyx

• responsible for protecting flowering bud from environmental factors and pests before reaching maturity.

petal

• one of the four floral organs

• located in the Corolla

• attracting pollinators for fertilization

stamen

• one of the four floral organs

• located in the Androecium

• male reproductive organ, responsible for pollen production and dispersal.

carpel

• one of the four floral organs

• located in Gynoecium

• female reproductive organ, facilitates and develops into fruit.

simple leaf

• type of leaf

• has entire or lobed blades

• single, undivided

compound leaf

• type of leaf

• divided into leaflets

• pinnate (like feather)

• or palmate (like hand)

lingin

• the “backbone” in plant cell walls, structural support and water transport.

synergid

• part of reproductive process within an angiosperm

• fertilization support through “guiding” pollen

• secretes chemical signals.