Definitions of terms from general biology and those specific to ferns

alternation of generations
life cycle alternating between gametophyte and sporophyte
allele
one of the alternative forms of a gene that occurs at the same locus
abscisic acid
a plant hormone. Abscisic acid reduces growth and sensitivity to antheridiogen in C-Fern gametophytes
antheridiogen
in ferns, a chemical substance (pheromone) secreted by gametophytes that causes immature gametophytes to develop as males
antheridium (a)
a male sexual organ(s) that produces sperm (spermatozoids); the sperm-producing sex organ of seedless plants, also fungi and algae
archegonial neck
the nipple-shaped external portion of an archegonium, below the base of which the egg is located
archegonium (a)
a female sexual organ(s) that contains a single egg; the egg-producing sex organ of seedless plants – such as ferns and mosses
axenic
in biology, a culture of a particular organism that is entirely free from all other contaminating organisms
buffer
a substance which can stabilize the pH of a solution by neutralizing the effects of acids or bases
cell
the fundamental structural unit of living organisms
cell wall
the exterior portion of the plant cell that surrounds the protoplast
chemoattractant
a chemical that can attract motile cells, such as sperm
chlorophyll
the green pigment in plant cells used in photosynthesis
chloroplast
a chlorophyll-containing organelle, i.e. plastid, in plants and algae
circinate vernation
the specialized pattern of leaf development that occurs in ferns in which the leaf unrolls from the fiddlehead
clone
an exact copy of an individual
cytoplasm
the protoplasm of a cell, not including the nucleus
diploid
having two sets of chromosomes
dominant
in genetics, a character state or the allele that controls it that is expressed in the phenotype even if another allele for the locus is present
dormant
inactive, not growing
egg
the female gamete
embryo
the developing diploid sporophyte resulting from the division of the zygote
etiolation
in plants, a growth response to the absence of light in which certain cells become elongated; in higher plants chlorophyll synthesis is also ceases
fern
a seedless and flowerless plant that has a vascular sporophyte with roots, stems, and fronds (leaves) that produces spores by meiosis and an independent non-vascular microscopic gametophyte stage that produces male and female gametes.
fertilization
the union of nuclei from female and male gametes
foot
the portion of the fern embryo that is embedded in the gametophyte
frond
a term used to denote the leaf in ferns
frond shape
dissected – having a margin with deep, narrow segments
entire – having a smooth margin without notches or indentations
filiform – composed of threadlike or extremely slender parts
lobed – having margins with indentation or notches
gamete
a haploid reproductive or sex cell that can fuse with another gamete to form a diploid zygote
gametophyte
the microscopic haploid phase of the fern life cycle that produces gametes
gene
a unit of heredity carried on the chromosome
genotype
the genetic (allelic) makeup of an individual
germination
the beginning of growth or development of a spore or seed
haploid
having one set of chromosomes
hermaphrodite
a gametophyte containing a meristem and both antheridia and archegonia
hermaphroditic
an organism with both male and female reproductive organs
heteromorphic
having different forms or shapes at different times during life cycle or development
heterosporous
producing two types of spores as a result of meiotic division
heterozygous
having two different alleles at the same locus
homozygous
having two identical alleles at the same locus
homosporous
producing one type of spore as a result of meiotic division
hybrid
a combination of two different types
imbibition
absorption of fluid by physical means
incompatibility
in plants, a situation where a particular combination is not viable.
indusium
a flap of tissue that covers a sorus
a false indusium is a a rolled-over leaf margin under which sporangia form and mature
leaf
the major photosynthetic organ of vascular plants
locus
the location of a gene on a chromosome.
male
a gametophyte lacking a meristem and containing numerous antheridia
meiosis
a process of cell division in sexually reproducing organisms that results in the reduction of chromosome number (usually half the number of chromosome of the original cell)
meristem
area of active cell division that gives rise to other cells and tissues
mineral
an inorganic substance necessary for normal growth
mutant
a genetic variant
neck canal cells
a row of cells present in the neck of an unopened archegonium
pH
a measurement of the acidity or relative concentration of hydrogen ions in a solution ( pH = -log [H+]). A neutral solution is pH 7; an acidic solution less than 7 and a alkaline or basic solution greater than 7
phenotype
the appearance of an organism that results from the interaction of its genotype and the environment
pheromone
a substance produced by one individual of a species that affects the development of other individuals in a population
phloem
the food conducting tissue of a vascular plant
photosynthesis (tic)
a biochemical process in green plants by which (typically) carbohydrates are synthesized from carbon dioxide and water using light as an energy source and releasing oxygen as a byproduct
pigment
any of a number of organic molecules that absorb and reflect light of particular wavelengths
polyploid
having more than double the basic chromosome number
prothallus (prothallium)
a structure produced from a developing spore that bears sex organs; sometimes used interchangeably with gametophyte
pteridophyte
a term commonly referring to ferns and fern allies such as horsetails and clubmosses
qualitative data
data expressed as a description of an inherent or distinguishing characteristic, property or trait
quantitative data
data expressed as number, measurement or quantity
recessive
in genetics, a character state (or the allele that controls it) that is expressed in the phenotype only if another identical allele for the locus is present; a recessive allele can be masked by a dominant allele.
rhizoid
a clear thread-like cell visible in germinating spores and at the base of gametophytes
root
the vascular organ of sporophytes typically associated with the substrate
root cap
the very tip portion of a root that is composed of a loose aggregation of friable cells
sample (sampling)
in statistics, a subset which is analyzed to be representative of the whole population
seed
an embryonic plant enclosed in a protective outer covering
seed plant
a plant that bears seeds
segregation
in genetics, the separation during meiosis of a pair of alleles at a given locus, resulting in gametes containing only a single allele per locus
sexual reproduction
reproduction based on the reciprocal processes of meiosis and fertilization
shoot
the aerial portion of a plant distinct from the root
sorus
a cluster or grouping of sporangia
species
a group of interbreeding individuals with similar characteristics
sperm (spermatozoid)
in ferns – a motile male gamete
spore
single-celled haploid (1n) product of meiosis that germinates and develops into a gametophyte
spore mother cell
a diploid (2n) cell which undergoes meiosis to produce haploid (1n) spores
sporophyte
the macroscopic diploid vascular stage of the fern life cycle that produces spores
strain
a group of plants distinguished by a particular trait
syngamy
the fusion of two gametes
variation
a deviation from the norm or standard type
wet mount
a preparation of tissues or cells placed in water on a slide and covered with a coverslip to allow viewing under a microscope
wild type
the phenotype selected as a standard for comparison with other phenotypes, often the predominant phenotype among individuals of species
xylem
the water-conducting tissue of a vascular plant
zygote
the diploid cell produced by the fusion of gametes