Plant Reproduction Flashcards
Diagram the ABC gene hypothesis in flower development.
If A gene is present we only get sepals, if A and b genes are present we get petals and sepals, if only B is present we get no sepals and petals only stamen, if b and c are present we get stamens and if all are present we get all 4
Explain how sperm travels to the egg in the four major plant phyla.
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Explain fruit development and how it relates to flower structure.
A fruit is the mature ovary (typically) of a flower. While the seeds are developing from ovules, the flower develops into a fruit The fruit protects the enclosed seeds and, when mature, aids in their dispersal by wind or animals. Fertilization triggers hormonal changes that cause the ovary to begin its transformation into a fruit. If a flower has not been pollinated, fruit typically does not develop, and the flower usually withers and falls away.
the ovary wall becomes the pericarp, the thickened wall of the fruit
Explain the purpose of seed dormancy
prevents seeds from germinating during unsuitable ecological conditions that would typically lead to a low probability of seedling survival
An important function of seed dormancy is delayed germination, which allows dispersal and prevents simultaneous germination of all seeds.
Seeds make it possible for embryos to survive in harsh conditions.
Sporogenesis
development of the mega/micro spores via meiosis
Gametogenesis
development of the gametes via mitosis
Antheridiogen
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pistil
A single carpel or a group of fused carpels.
anther
In an angiosperm, the terminal pollen sac of a stamen, where pollen grains containing sperm-producing male gametophytes form.
Thrum flower
Long stamens, short styles
Pin flower
Long styles, short stamens
Micropyle
Space between integuments
remains open until pollination can occur
Epicotyl
embryonic axis above the cotyledons
Hypocotyl
embryonic axis below the cotyledons
Radicle
embryonic root
Seed
An adaptation of some terrestrial plants consisting of an embryo packaged along with a store of food within a protective coat.
Simple fruit
derived from a single carpel or fused carpels (ie. Most frui
Aggregate fruit
from a single flower, with each carpel forming a fruit (ex. Raspberries)
Multiple fruit
develops from a cluster of flowers that fuse together (ex. Pineapples)
Accessory fruit
fruit formed from other floral parts that are not the carpels (ex. Apples and strawberries)
Dormancy
A condition typified by extremely low metabolic rate and a suspension of growth and development.
Imbibition
The physical adsorption of water onto the internal surfaces of structures.
What are the 3 Fs of Angiosperms?
Flowers, Double fertilization, fruits
What are flowers composed of?
Flowers are composed of 4 whorls of floral organs
Carpels -> megasporophylls composed of stigma, style, ovary(MEGASPORANGIA)
Stamens->microsporophylls composed of anthers(SPORANGIA), filaments
Petals -> showy, inner whorl
Sepals -> green (usually), outer whorl
Carpels
megasporophylls composed of stigma, style, ovary(MEGASPORANGIA)
The ovule-producing reproductive organ of a flower, consisting of the stigma, style, and ovary.
Stamens
microsporophylls composed of anthers(SPORANGIA), filaments
The pollen-producing reproductive organ of a flower, consisting of an anther and a filament.
Petals
showy, inner whorl
A modified leaf of a flowering plant
Petals are the often colourful parts of a flower that advertise it to insects and other pollinators
Sepals
green (usually), outer whorl
A modified leaf in angiosperms that helps enclose and protect a flower bud before it opens
receptacle
site of attachment of all whorls
incomplete flower
missing 1 or more whorls, includes unisex flowers
inflorescences
clusters of flowers (as opposed to a single flower)- wheat
Carpellate flower
female only(missing stamen),
staminate flower
male only