Download Plant Reproduction 2 Not involving gamete formation. No sex

Plant Reproduction 2
Not involving gamete formation. No sex involved.
asexual
A plant that takes two years (i.e. two growing seasons) to complete
its life cycle, e.g. parsnip, carrot, etc. In the first year, the seeds
germinate and grow into a plant which produces and stores food in
an underground perennating organ, and the foliage above ground
usually dies back in autumn. In the second year, new shoots arise
from the underground organ to produce flowers and seeds.
biennial
A type of capsule containing seed. Seed are dispersed through small
openings when the capsule is shaken by the wind, e.g. poppy.
censer
The transfer of pollen from the anther of the stamen of one flower
to the stigma of the carpel of another flower on a different plant of
the same species.
cross pollination
The bursting open or splitting of a plant structure (e.g. capsule, seed
pod, fruit or anther) to release its contents.
dehiscence
A period of rest, inactivity or non-vegetative state before growth,
during which the rate of metabolism is reduced, e.g. in buds, seeds
and spores. Seeds will not germinate during this time, even if given
ideal conditions, because other requirements may be necessary
before germination can occur.
This is a characteristic of angiosperms. The pollen tube carries two
sperm nuclei to the female embryo sac in the ovule. One sperm
nucleus fuses with the egg cell and gives rise to a diploid embryo.
The other sperm nucleus fuses with the two polar nuclei to form a
triploid endosperm nucleus.
Large oval cell in nucellus of ovule. Female gametophyte of
angiosperm. Produces an ovum at micropylar end and two polar (or
endosperm) nuclei in the centre.
dormancy
double
fertilization
embryo sac
A seed whose main food store is in the endosperm, e.g. maize. This
food store is used by the embryo for its growth.
endospermic seed
Part of a plant embryo/seedling above the cotyledons. Gives rise to
the shoot.
epicotyl
Thick outer wall of a pollen grain.
exine
The stalk of the anther (i.e. the pollen producing part of flower).
filament
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An asexual method of reproduction where parts of an organism
break off and are capable of developing into a new organism, e.g.
fragmentation
seaweeds, bacteria, fungi (yeast).
Any cell which must fuse with another cell in order to produce a new
individual. A haploid reproductive cell, i.e. it contains half the
gamete
required genetic information for the formation of a new individual
or half the somatic number of chromosomes.
Found in the pollen grain and divides by mitosis after pollination to
form two male gamete nuclei.
generative
nucleus
Method of plant propagation where scion is attached to stock, e.g.
apple trees.
grafting
Part of a plant embryo/seedling below the cotyledons. Gives rise to
the radicle, produces the root.
hypocotyl
Inner and outer layers which surround a mature ovule in a flowering
plant to form the testa (seed coat). Small opening remains called the
micropyle.
A method of artificial/vegetative propagation where a branch of a
plant is bent over and pinned to the earth at a node. When roots
develop the branch is separated from the parent plant.
The cell that undergoes meiosis to produce the megaspore. Also
called the embryo sac mother cell.
The growing of a new plant from a small piece of stem, leaf or root
tissue in a container of sterile nutrient medium which contains
hormones and growth substances.
Cells in the pollen sacs from which microspores (pollen grains) are
produced. In flowering plants, the microspore is the pollen grain,
and contains three nuclei.
Nutritive tissue found in the ovule and nourishes the embryo sac
during its development.
integuments
layering
megaspore
mother cell
micro-propagation
microspore
mother cell /
pollen mother cell
nucellus
In ovary of flower, consists of nucellus, embryo sac and integuments.
ovule
When fertilised, develops into the seed.
Of plants. Surviving adverse conditions (winter) by storing food in an
underground stem or tap root. This food is used to produce new
growth the following spring.
perennation
Terminal bud or epicotyl of embryo in seed plan
plumule
Microspores of seed plants (angiosperms and gymnosperms)
produced by a pollen mother cell in the pollen sac. Contains two
nuclei – tube and generative. The generative nucleus produces the
male gametes.
pollen grain
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Slender tube formed on germination of pollen grain; carries the two
sperm nuclei to the opening of the embryo sac at the micropyle.
pollen tube
The tips of a flower stalk (pedicel) on or around which the flower
parts develop.
receptacle
Outgrowth from plant growing horizontally over the soil surface.
Forms roots near its tip and the terminal bud sends up a new shoot,
e.g. strawberry, creeping buttercup.
runner(s)
A mature/ripened ovule consisting of an embryo and food store
which can give rise to a new individual.
seed
Method used to scatter/spread seed from the parent plant using
explosive pods, e.g. pea, gorse, lupin, etc.
self- dispersal
The transfer of pollen from the anther of the stamen of one flower
to the stigma of the carpel of the same flower or another flower on
the same plant.
Reproduction involving the production, transfer and union of sex
cells or gametes and development of the embryo. Two parents
involved (plant or animal), one male and one female.
self-pollination
sexual
reproduction
Structure in a flower that produces pollen, consists of anther and
filament.
stamen
The stump, butt or main trunk onto which the scion is grafted.
stock
In the anther of the stamen, a layer of nutritive cells surrounding the
pollen sacs.
tapetum
One of the nuclei in the pollen grain in seed plants. It grows down
through the stigma, style, and into the ovule, followed by the two
male gamete nuclei to enter the embryo sac through the micropyle.
tube nucleus
Capable of growth, development and sustaining life. Term used
when describing foetus or dormant seed.
viable
Method used to scatter/spread seed from the parent plant using
wind, e.g. grasses.
wind dispersal
A diploid cell resulting from the union of two haploid gametes, i.e. a
fertilised egg.
zygote
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