Please enable JavaScript.
Coggle requires JavaScript to display documents.
Flowers and Reproduction (Flower structure and cross-pollination…
Flowers and Reproduction
Asexual reproduction
Fragmentation
Large spreading or vining plant grows to several meters in length
Individual parts become self-sufficient
Establish adventitious roots
If a middle portion dies, the ends become separated
Sexual reproduction
The plant life cycle
Gametes
Haploid sex cells
Sperm or egg
Syngamy or fertilization
Fusion of gametes
Sporophyte phase
Trees, shrubs, and herbs
Always diploid
Meiosis results in haploid spores
Spores undergo mitosis
Become a haploid gametophyte
Alternation of generations
Life cycle with two generations
Flower structures
Pedicel
Flower stalk
Receptacle
Other end of axis where other flower parts attach
Floral appendages
Sepals
Lowermost and outermost of the floral appendages
Surround and enclose other flower parts as they mature
Complete flowers have all four
Petals
Above the sepals
Stamens
Above the petals
Known collectively as the androecium
Two parts
Filament
Anthers
Carpals
Gynoecium
Three main parts
Stigma
Catches pollen grains
Style
Elevates stigma to a useful position
Ovary
Where megaspores are produced
Gametophytes
Microgametophyte
Developed from microspores
Megagametophyte
Develops from megaspores
Embryo sac
Multinucleate megagametophyte
Fertilization
Plasmogamy
Fusion of the protoplasts of the gametes
Karyogamy
Fusion of the nuclei
Embryo and seed development
Suspensor
Stalk-like structure which pushes the embryo deep into the endosperm
Torpedo stage
Short axis
Radicle
Epicotyl
Hypocotyl
Albuminous seed
Mature seed in which endosperm is rather abundant
Exalbuminous
Endosperm is sparse or absent at maturity
Fruit development
Ovary matures into a fruit
Three layers
Exocarp
Mesocarp
Endocarp
Flower structure and cross-pollination
Cross-pollination
Pollination of a carpel by pollen from a different individual
Self-pollination
Pollination of a carpel by pollen from the same flower
Stamen and style maturation times
Anthers and stigmas mature at different times
Self-fertilization prevented
Stigma and pollen incompatibility
Compatibility barriers
Chemical reations between pollen and carpels that prevent pollen growth
Monoecious and dioecious species
Essential organs
Stamens and carpels
Perfect flower
Has the two essential organs
Dioecious
Some produce staminate flowers
Others produce carpellate flowers
Monoecious
Staminate flowers located on same plant with carpellate flowers
Animal-pollinated flowers
Probability of pollen reaching a stigma is improved
Coevolution
Flower becomes adapted for specific insect
Insect becomes adapted for efficient exploitation of flower
Wind-pollinated flowers
Attracting pollinators is unnecessary
Ovary position
Inferior ovary
The primordia create a thick layer of protective tissue
Ovary appears to be located below the other organs
Superior ovary
No fusion to the ovary occurs
Ovary is obviously above the other flower parts
Inflorescences and pollination
Inflorescence
Many flowers grouped together
Arrangements
Determinate
Has only limited potential for growth
Apex is converted to a flower, ending growth
Indeterminate
Lowest, outermost flowers open first
New flowers are still being initiated at the apex
Fruit types and seed dispersal
True fruits and accessory fruits
True fruit
Fruit containing only ovarian tissue
Accessory fruit
Used if any nonovarian tissue is present
Simple fruit
Develops from a single ovary or fused ovaries of one flower
Aggregate fruit
Separate carpels of one gynoecium fuse during development
Multiple fruit
All individual fruits of an inflorescence fuse during development
Classification of fruit types
Dry fruit
Typically not eaten by natural seed-distributing animals
Fleshy fruit
Eaten during the natural seed distribution process
Dehiscent fruits
Break open and release seeds
Indehiscent fruits
Do not break open to release seeds
