Seedless plants

nonvascular plants

plants without a vascular system consisting of xylem and phloem

vascular plants

a plant that is characterized by the presence of conducting tissue

lignin

a class of complex organic polymers that form key structural materials in the support tissues of most plants

xylem

vascular plant tissue that conduct water and minerals upward from the roots to the rest of the plant

phloem

vascular plant tissue that transport sugar and other organic nutrients throughout the plant

waxy cuticle

a waxy covering on the epidermis that protects plans from desiccation

stomata

a microscopic pore surrounded by guard cells in the epidermis of leaves and stems that allows gas exchange between the environment and the interior of the plant

secondary metabolites (related to poisons in plants)

tiny organic molecules that form from primary metabolites during plant metabolism

sweet metabolites (related to pollination)

alternation of generations

a life cycle that alternates between 2 multicellular phases

gametophyte

the gamete- producing and usually haploid phase, producing the zygote from which the sporophyte arises

Gametes

a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote

Zygote

a diploid cell resulting from the fusion of two haploid gametes

sporophyte

the asexual and usually diploid phase, producing spores from which the gametophyte arises

Spores

surrounded by thick cell walls containing a tough polymer known as sporopollenin in seedless plants

haploid (n)

one copy of each chromosome

diploid (2n)

two copies of each chromosome

haplontic

having a life cycle in which the main form is haploid with a diploid zygote being formed only briefly

diplontic

having a life cycle in which the main form is diploid

Streptophytes

a group of green algae from which land plants originated

Bryophytes

nonvascular, seedless plants (liverworts, hornworts, mosses)

roots

the part of the plant which attaches it to the group or to a support

leaves

a flattened structure of a higher plant that is attached to a stem directly or via a stalk. The main organ of photosynthesis and transpiration

sporophylls

a modified leaf that bears sporangia

vascular tissue

the tissue in higher plants that constitutes the vascular system, consisting of phloem and xylem, by which water and nutrients are conducted throughout the plant.

rhizoids

a filamentous outgrowth or root hair on the underside of lower plants that serves ti anchor the plant and conduct water

microphyll

a leaf with single unbranched veins and no demonstrable gap around the leaf trace

megaphyll

a leaf with several or many large beans branching apart or running parallel and connected by a network of smaller veins

sporangia

a multicellular organ in which meiosis occurs and haploid cells develop

fern frond

the leaves of the plant on a fern

sori (sorus = singular)

a cluster of sporangia on a fern sporophyll

vascular, seedless plants

club mosses, whisk ferns, horsetails, ferns