Plant Reproduction and Development Flashcards
An organism that moves pollen grains from one plant to another
Pollinator
- Male reproductive part of a flower
- Consists of a thin filament with a pollen-producing anther at the tip
- Spores (pollen) produced by meiosis in anthers develop into immature male gametophytes (pollen grains)
Stamen
- Female reproductive part of a flower
- Consists of a sticky or hairlike stigma, a style, and a chamber (ovary) with one or more ovules
- Spores produced in ovules by meiosis develop into female gametophytes
Carpel
The enlarged base of a carpel, inside which one or more ovules form, and eggs are fertilized
Ovary
- Structure in which a haploid, egg-producing female gametophyte forms
- Develops from a mass of ovary wall tissue inside carpels; after fertilization, matures into a seed
Ovule
•Walled haploid spore; gives rise to a pollen grain
Microspore
Haploid spore that forms in ovary of seed plants
Megaspore
Arrival of pollen on a receptive stigma
Pollination
- One sperm cell in the pollen tube fertilizes the egg, forming a diploid zygote
- The second sperm cell fuses with the endosperm mother cell and gives rise to triploid endosperm
Double Fertilization
A cell with two nuclei (n + n) that is part of the female gametophyte of a flowering plant
Endosperm mother cell
Triploid nutritive tissue in the seeds of flowering plants; sustains the sporophyte seedling
Endosperm
•Consists of the embryo sporophyte and its food reserves inside a protective seed coat
Seed
Mature ovule of a seed plant
Seed
Mature ovary, often with accessory tissues that develop from other parts of a flower
Fruit
Form of asexual reproduction in plants; new roots and shoots grow from extensions or fragments of a parent plant
Vegetative reproduction
branch from the main stem of the plant, near the ground
Stolons
thickened underground stems that store nutrients (tubers)
Corms
flattened stems of succulents
Cladodes
Laboratory method in which body cells are induced to divide and form an embryo
Tissue culture propagation
Fruits may form in the absence of fertilization
Seedless fruits or parthenocarpic fruits
Fruits may form in the absence of fertilization examples
blackberries, dandelions
Fruit may continue to form after ovules abort
Seedless fruits or parthenocarpic fruits
Examples of Fruit may continue to form after ovules abort
seedless grapes, navel oranges
Fruits of sterile polyploid plants
Seedless fruits or parthenocarpic fruits
Examples of Fruits of sterile polyploid plants
Seedless bananas (3n), watermelons (4n)
- Induces stem elongation, helps seeds break dormancy
* Role in flowering in some species
Gibberellin
Promotes elongation, cell division, and differentiation in apical meristems
•Inhibits abscission, lateral bud growth
Auxin
Growth-inhibiting effect on lateral buds, mediated by auxin produced in shoot tips
Apical dominance
Promotes cell division; releases lateral buds from apical dominance
Cytokinin
Gaseous plant hormone that inhibits cell division in stems and roots; also promotes fruit ripening
Ethylene
Stimulates stomata to close in response to water stress; induces dormancy in buds and seeds
Abscisic acid (ABA) •
In plants, directional growth response to an environmental stimulus such as gravity, light, contact, or mechanical stress
tropism
Plant growth in a direction influenced by gravity
Gravitropism
Change in the direction of cell movement or growth in response to a light source
Phototropism
Redirected growth of a plant in response to contact with a solid object
Thigmotropism
Internal time-measuring mechanism by which individuals adjust their activities seasonally, daily, or both in response to environmental cues
Biological clock
Biological activity repeated about every 24 hours
Circadian rhythm
Light-sensitive pigment that helps set plant circadian rhythms based on length of night
•Triggers transcription of genes active in tropisms, photosynthesis, germination, and flowering
Phytochrome
Biological response to seasonal changes in the length of night relative to length of day
Photoperiodism
Stimulation of flowering in spring by cold winter temperatures
Vernalization
Phase in a life cycle from maturity until death; also applies to death of parts, such as leaves
Senesence
Period of arrested growth, ended only by specific environmental cues
•Usually preceded by abscission
Dormancy
Process of shedding plant parts in response to seasonal changes, drought, injury, or nutrient deficiency
Abscission
Any agent that moves pollen grains from one plant to another; often a coevolved animal
Pollination vector
Sweet fluid exuded by some flowers
•Attracts pollinators such as butterflies, hummingbirds, and honeybees
Nectar
Opposite of evergreen trees like pine trees
Deciduous
Fleshy outgrowths that can be eaten
Aril
Water-pollinated
Hydrophilous
Water dispersed
Hydrochory
Fruits that develop from an pvary
True fruits
stem of ginger
rhizoids
stems of potato
tuber
eyes of potato
nodes
example of stolon
bermuda grass
Spore bearing plants
Pteridophyte a