Seed Development and Germination in Dicotyledons

Seed structure (Dicotyledons) with endosperm: Testa (seed coat) Endosperm (nutrient storage) Cotyledon Shoot apex Hypocotyl Radicle (embryonic ______) Hilum (breakpoint of funicle) without endosperm Storage cotyledons Embryo bipolar: a shoot pole and a root pole are present

Nutrient storage in the endosperm: Cotyledons thin and plane, elevated above ground level by elongation of the hypocotyl, become green and perform photosynthesis  ______ germination

Nutrient storage in the cotyledons: Endosperm lacking, cotyledons thick, remaining in the testa and in the ground, respectively no elongation of the hypocotyl  ______ germination

Seed structure (Dicotyledons) Correlation between nutrient storage and germination  ______ germination

Hypogeal germination often takes place in seeds germinating ______ ground

Seed burial is not a precondition of ______ germination

Epigeal germination often takes place in seeds ______ in the ground

In hypogeal seedlings storage does not always take place in the ______ (presence of endosperm)

There is no strict correlation between storage type (endosperm/cotyledons) and germination ______

Cotyledons or parts of them may take over haustorial function transmitting nutrients from the endosperm to the ______

Seedlings of ______ Reduction of the leafy part in the megasporophylls

Formation of female cones ______ Cycas Dioon Macrozamia

Testa differentiation into 4 layers Exotesta (coarse outer skin) Embryo ______ (fleshy) Sclerotesta

Embryo differentiation: 2 cotyledons (co) hypocotyl root meristem (wm; radicle) (embedded in suspensor ______)

Cotyledons remain small (no storage of nutrients.), remain within the ______ cover (except basal parts) and have haustorial function

Benzylisoquinolines (BIA) include the alkaloids morphine and codeine from the plant ______

The biosynthesis of simple Isoquinolines occurs via the conversion of ______ to dopamine

Isoquinolines are the largest group of plant alkaloids, with approximately ______ different types

______ is induced quickly in seedlings of the Papaver plant, shortly after germination

Benzylisoquinolines are compartmentalized in various plant parts such as phloem, vessels, and ______

Morphine and codeine are stored in the vesicles of ______ networks in the Papaver plant

Blocking the last steps of ______ biosynthesis leads to the production of morphine in cytoplasmic vesicles

______ is used as a narcotic analgesic and is stored in the vesicles of laticifer networks

Benzylisoquinolines have functions such as feeding deterrent, insecticidal, antifungal, antibacterial, and ______

Papaver somniferum is a medicinal plant that has been domesticated since the ______ age

Alkaloids are cyclic compounds containing N in negative oxidation state and of limited distribution in living organisms. There are approximately ______ structures with great structural diversity and varied biosynthetic origin. Alkaloid bearing species can be found in nearly all classes of organisms, including frogs, ants, butterflies, bacteria, sponges, fungi, spiders, beetles, and mammals. Insects use plant alkaloids as a source of attractants, pheromones, and defense substances. Approximately 30-40% of angiosperms contain alkaloids, selectively in tissues or in the whole plant, mostly constitutive defense chemicals. Alkaloids have a wide range of physiological effects, including antibiotic activity, feeding deterrents, and toxicity to insects, mammals, and humans. They are frequently classified according to ring structure, but structural alignment may not reflect biosynthetic origin, and the source of nitrogen may be unknown. Alkaloids are mostly formed from L-amino acids (AA) or in combination with other building blocks such as terpenoids. They may convert AA precursors to very specific secondary metabolites through one or two transformations.

Alkaloids are mostly formed from L-amino acids (AA) or in combination with other building blocks such as terpenoids. They may convert AA precursors to very specific secondary ______ through one or two transformations.

Approximately 30-40% of ______ contain alkaloids, selectively in tissues or in the whole plant, mostly constitutive defense chemicals.

Insects use plant alkaloids as a source of attractants, pheromones, and defense substances. Approximately 30-40% of angiosperms contain alkaloids, selectively in tissues or in the whole plant, mostly constitutive defense chemicals.

Alkaloids have a wide range of physiological effects, including ______ activity, feeding deterrents, and toxicity to insects, mammals, and humans. They are frequently classified according to ring structure, but structural alignment may not reflect biosynthetic origin, and the source of nitrogen may be unknown.

Alkaloids are frequently classified according to ______ structure, but structural alignment may not reflect biosynthetic origin, and the source of nitrogen may be unknown.