CH30 BIO111

Double fertilization

A mechanism of fertilization in angiosperms in which two sperm cells unite with two cells in the female gametophyte (embryo sac) to form the zygote and endosperm.

Fertilization

The union of haploid gametes to produce a diploid zygote

Biomass

The total mass of organic matter comprising a group of organisms in a particular habitat

Callus

A mass of dividing, undifferentiated cells growing at the site of a wound or in culture

Self Incompatibility

The ability of a seed plant to reject its own pollen and sometimes the pollen of closely related individuals.

Anther

In an angiosperm, the terminal pollen sac of a stamen, where pollen grains containing sperm producing male gametophytes form

Dioecious

In plant biology, having the male and female reproductive parts on different individuals of the same species

Endosperm

In angiosperms, a nutrient rich tissue formed by the union of a sperm with two polar nuclei during double fertilization; provides nourishment to the developing embryo in angiosperm seeds.

Inflorescence

A group of flowers tightly clustered together

Ovule

A structure that develops within the ovary of a seed plant and contains the female gametophyte

Stigma

The sticky part of a flower’s carpel, which receives pollen grains

Imbibition

The uptake of water by a seed or other structure, resulting in swelling

Pollination

The transfer of pollen to the part of a seed plant containing the ovules, a process required for fertilization

Vegetative Propagation

Cloning of plants by humans

Carpel

The ovule producing reproductive organ of a flower, consisting of the stigma, style and ovary

Dormancy

A condition typified by extremely low metabolic rate and a suspension of growth and development

Complete Flower

A flower that has all four basic floral organs; sepals, petals, stamens, and carpels

Ovary

In flowers, the portion of a carpel in which the egg containing ovules develop

Radicle

An embryonic root of a plant

Megaspore

A spore from a heterosporous plant species that develops into a female gametophyte

Coevolution

The joint evolution of two interacting species, each in response to selection imposed by the other

Biofuel

A fuel produced from biomass

Coleoptile

The covering of the young shoot of the embryo of a grass seed

Microspore

A spore from a heterosporous plant species that develops into a male gametophyte.

Pistil

A single carpel (simple) or a group of fused carpels (compound)

Fragmentation

A means of asexual reproduction whereby a single parent breaks into parts that regenerate into whole new individuals

Asexual Reproduction

The generation of offspring from a single parent that occurs without the fusion of gametes. In most cases, the offspring are genetically identical to the parent.

Apomixis

The ability of some plant species to reproduce asexually through seeds without fertilization by a male gamete

Accessory fruit

A fruit, or assemblage of fruits, in which the fleshy parts are derived largely or entirely from tissues other than the ovary

Simple Fruit

A fruit derived from a single carpel or several fused carpels.

Fruit

A mature ovary of a flower. The fruit protects dormant seeds and often aids in their dispersal

Style

The stalk of a flower’s carpel, with the ovary at the base and the stigma at the top.

Stamen

The pollen producing reproductive organ of a flower, consisting of an anther and a filament

Incomplete Flower

A flower in which one or more of the four basic floral organs are either absent or nonfunctional

Multiple fruit

A fruit derived from an entire inflorescence

Stock

The plant that provides the root system when making a graft

Pollen tube

A tube that forms after germination of the pollen grain and the functions in the delivery of sperm to the ovule

Epicotyl

In an angiosperm embryo, the embryonic axis above the point of attachment of the cotyledon(s) and below the first pair of miniature leaves

Embryo Sac

The female gametophyte of angiosperms, formed from the growth and division of the megastore into a multicellular structure that typically has eight haploid nuclei

Coleorhiza

The covering of the young root of the embryo of a grass seed

Aggregate Fruit

A fruit derived from a single flower that has more than one carpel

Vegetative Reproduction

Cloning of plants in nature

Transgenic

Pertaining to an organism whose genome contains DNA introduced from another organism of the same or a different species

Petal

A modified leaf of a flowering plant. Often colorful and advertise the flower to insects and other pollinators

Scion

The twig grafted onto the stock when making a graft

Sepal

A modified leaf in angiosperms that helps enclose and protect a flower bud before it opens

Totipotent

Describing a cell that can give rise to all parts of the embryo and adult, as well as extra embryonic membranes in species that have them.

Seed coat

A tougher outer covering of a seed, formed from the outer coat of an ovule. In a flowering plant, it encloses and protects the embryo and endosperm.

Receptacle

The base of a flower; the part of the stem that is the site of attachment of the floral organs

Pollen Grain

In seed plants, a structure consisting of the male gametophyte enclosed within a pollen wall.

ABC Hypothesis

A model of flower formation identifying three classes of organ identity themes that direct formation of the four types of floral organs

Hypocotyl

In an angiosperm embryo, the embryonic axis below the point of attachment of the cotyledon(s) and above the radicle.