Biology Test- Plant Structure, Growth, and Reproduction (Topics 9.3 and 9.4) Flashcards
Pollination
The transfer of pollen from the anther to the stigma (usually occurs between different plants)
Fertilization
The fusion of the male gamete nuclei (in pollen) with the female gamete nuclei (in ovule)
Seed Dispersal
The fertilized ovule (seed) moves away from the parent plant to reduce the competition for growth
Flowers Development
Develop from changes in gene expression in the shoot apex
Flowers & Pollinator
Mutualistic relationship in order to reproduce. Plants get a mechanism of pollen transfer and the animal gains a source of nutrition.
Pistil
Female structure (Stigma, style, ovule)
Stamen
Male structure (anther, filament)
Photoperiodism
is the response of the plant to the length of day or night and controls flowering
Phytochrome
regulates flowering, exists in Pr and Pfr form, reverts to inactive red form at night
Pr
inactive red form, absorbs red light to become Pfr
Pfr
active far red form which is predominant during the day, absorbs red light and forms Pr
Germination
process by which a seed emerges from a period of dormancy and sprouts to form a new plant
Germination Condtions
oxygen to produce ATP via aerobic respiration, water to metabolically activate the cells, suitable temperature and pH for enzyme activity
Long Day Plants
Pfr activates flowering which is induced when the night length is short
Short Day Plants
-Pfr inhibits flowering which is induced when the night length is over 12 hours
Meristems
undifferentiated cells in a plant that are capable of indeterminate growth
Meristem Regions
specific regions of growth or development and allow for regrowth and vegative propagation.
Meristematic Tissues
Either apical or lateral
Apical Tissue
occurs in shoots & roots, is responsible for primary growth (lengthening) and leaf development
Lateral Tissue
occurs at the cambium, is responsible for secondary growth (widening) and the production of bark
Auxin Release
release by the shoot apical meristem & coordinates both apical growth and directional growth (tropism)
Auxin Influences..
cell growth rates by changing the pattern of gene expression within the plant tissue
Auxin efflux pumps
set up concentration gradients of auxin in plant tissues to allow for differentiated growth rates
Auxin
a plant hormone that controls growth in the shoot apex by stimulation of inhibition cell division (mitosis)
Apical Growth
growth in the shoot apex allows for extension of the stem and the development of leaves (primary growth)
Apical Growth (Stem)
occurs in sections called nodes, with the remaining meristem tissue forming inactive axillary bud which have the potential to form new shoots
Apical Dominance
Auxin promotes growth in apex but inhibit growth in buds (vertical growth)
Tropisms
the turning of an organism in response to a direction external stimulus
Tropism Example
Phototropism in response to light
Tropisms differ
according to the type of plant tissue, in plant shoots auxin promotes cell elongation, in plant roots auxin inhibits cell elongation
Micropropagation
a vitro technique used to produce large numbers of identical plants from a selected stock plant
Micropropagation Steps
Tissue sample is grown in agar and treated with growth hormones, growing shoot sare divided and transferred to soil to form new plants
Micropropagation Uses
rapid bulking up of new plant varieties, production of virus-free stains of existing varieties, the propagation of rare plant species.
Shoot Apex
very top of the shoot of the plant which is the stem together with the leaves
Self Pollination
Pollen from anther of same plant falls on its own stigma (less genetic variation)
Cross Pollination
Pollen from anther of one plant carried to stigma of different plant (increased genetic variation, but long distance for pollen to travel)
Angiosperms
Flowering plants
Gymnosperms (conifers)
Seeds are in cones (naked seeds)
Filicophytes
Have pinnate leaves (leaflets on stalks), reproduce using spores released from sor, ex: fern
Bryophytes
Small, lacks leaves & stems, no xylem/phloem tissue, reproduce using spores, ex: mosses.
Monocots
(one cotyledon, fibrous roots, scattered vascular, leaf parallel veins, multiples of 3 flowers
dicots
two cotyledon, tap roots, ringed vascular, not-like veins leaf, 4 or 5 flowers
Gymnosperms & Dicots
only types of plants that have both apical and lateral meristems
Vectors for Seed Dispersal wind, water, animals
wind, water, animals
Adaptations of flowers to attract pollinators
large, brightly colored, scented flowers, sticky pollen grains
