Introduction to Plants
Terms
Alternation of Generations
-
The fluctuation between the diploid (sporophyte) and haploid
(gametophyte) life stages that occurs in plants.
Angiosperm
-
A vascular flowering plant in which seeds are enclosed inside of protective
ovaries.
Autotroph
-
An organism that synthesizes its own organic nutrients and does not rely on
other organisms for food.
Bryophyte
-
A lower terrestrial plant (often a moss or liverwort) that lacks a vascular
system and is dependent on environmental moisture for reproductive and nutritive
functions.
Bulb
-
Roughly spherical underground bud containing additional buds that can develop
asexually into new plants.
Chlorophyll
-
A green pigment, necessary for photosynthesis, that is found in the
chloroplasts of plants.
Dicot
-
An flowering plant (angiosperm) that possesses two
cotyledons during embryonic development.
Diploid
-
Having two sets of chromosomes, one from each parent.
Gamete
-
A haploid sex cell (either an egg or sperm cell); male and female
gametes join during fertilization to create a diploid zygote.
Gametophyte
-
A haploid plant or plant structure that produces haploid gametes through
mitosis.
Grafting
-
An artificial form of vegetative propagation in which parts of two young
plants are joined together, first by artificial means and then by tissue
regeneration.
Gymnosperm
-
A vascular non-flowering plant (commonly known as a conifer) in which seeds are
not protected by an ovary.
Haploid
-
Having only one set of chromosomes.
Hormone
-
A chemical that affects the ways in which an organism functions; it is produced
in one part of the plant body but, by traveling to target
cells throughout the body, affects many other
parts as well.
Jacket Cell
-
A component of the cell layer that covers the reproductive organs of plants and
prevents them from drying out.
Monocot
-
A flowering plant (angiosperm) that possesses one
cotyledon during embryonic development.
Ovary
-
In plants, the protective structure that holds the ovules and surrounds the
angiosperm seed; after fertilization, develops into a fruit.
Ovule
-
Structure that contains the female gametophyte and gametes; after
fertilization, develops into a seed.
Phloem
-
Vascular tissue composed of cells that are living at maturity; transports
the products of photosynthesis throughout the plant body.
Photosynthesis
-
The process by which plants and other autotrophic organisms convert light
energy into organic materials.
Pollen Grain
-
The male gametophyte of gymnosperms and angiosperms.
Root
-
The part of a plant beneath the soil; responsible for collecting water and
minerals from the soil, storing nutrients, and securing the plant to the ground.
Root Hair
-
An outgrowth of a plant root that provides an increased surface area for the
absorption of water and dissolved minerals from the soil.
Runner
-
Slender horizontal stem that can give rise, via specialized nodes, to new
plants.
Shoot
-
The part of the plant above the soil, including all aerial structures such as
stems, leaves, flowers, and fruits; gathers carbon dioxide and light energy for
photosynthesis, provides surfaces for gas exchange, and contains the plant's
reproductive organs.
Sporophyte
-
A diploid plant or plant structure that produces haploid spores through
meiosis.
Stoma
-
A very small epidermal pore, surrounded by two guard
cells, through which gases diffuse in
and out of a leaf.
Tracheophyte
-
A terrestrial plant with a vascular system.
Tuber
-
Fleshy underground storage structure, composed of an enlarged portion of the
stem, that has on its surface buds capable of producing new plants.
Vascular System
-
Mechanism of internal water and nutrient transport, made up of the vascular
tissues xylem and
phloem, that is characteristic of
tracheophytes.
Vascular Tissue
-
A conductive component (either xylem or
phloem) of the system that transports food
and nutrients throughout the plant body.
Vegetative Propagation
-
A form of asexual reproduction in which plants produce genetically identical
offshoots (clones) of themselves, which then develop into independent plants.
Xylem
-
Vascular tissue composed of cells that are dead at maturity; transports
water and dissolved minerals upwards from the roots to the shoot.
