germination Flashcards
what do seeds need for germination
correct environmental cues
what first comes out of the seed
the root
what becomes the seed coat
the integument
how many sperm nuclei are in angiosperms
two, causes double fertilization
what forms endosperm
sperm uniting with polar nuclei
embryo sac
female gametophyte
protoderm
outside layer of plant body
what surrounds the embryo
endosperm
procambium
gives rise to vascular tissues including xylem and phloem
microphyle
opening into ovule for sperm tube
megasporocyte function
goes through meiosis to form haploids in angiosperms
gymnosperm properties
don’t have ovaries, megasporocyte turns into female gametophytes which is the food source
apical meristem
where mitosis occurs
radicle
root tip
hypocotyl
stem below cotyledon
how many cotyledons do monocots have
one
scutellum
cotyledon
germination defintion
series of complex processes which initiate growth, begins with imbibition, followed by increased respiration, results in emergence of radicle (embryonic root)
what happens when the seed coat is broken down during imbibition
acid is released causing amylase to be released, amylase converts starch to sugar
eudicot properties
two cotyledons in seed for food storage
have epigeous germination, where the hypocotyl elongates, and cotyledons are above the ground
monocot properties
one cotyledon, large endosperm not absorbed by cotyledon stays in seed for food storage
have hypogeous germination where the epicotyl elongates, and the cotyledon remains below the ground
dormancy
delay in germination
primary dormancy
when seed is not immediately able to germinate after ripening or harvest
secondary dormancy
when seed is exposed to extreme stress and dormancy is induced
physiological dormancy
specific treatment must be given to embryo in order to initiate growth
steps include stratification, soaking after ripening
serotiny
use of fire to help growth occur
physical or seed coat dormancy
when a hard seed coat prevents imbibition
scarification
method to damage the seed coat
plant reproduction
is vegetative (no meiosis), seeds produced asexually (no meiosis or partial meiosis) or sexually (meiosis)
stolons and rhizomes
stolons are aboveground modified stems
rhizomes are underground modified stems
division of bulbs/cormels
underground rosette stems, includes onions and tulips
suckers
formation of buds on roots near the surface
clonal fragmentation
when plant pieces form independent plants
plantelets
little plants on the edge of leaves
bulbis
tiny bulblike organs produces in inflorescences or leaf axils
agamospermy
production of seeds asexually, no meiosis or partial meiosis, includes raspberries, grasses, dandelions
parthenogenesis
diploid embryo sac/ somatic cell divides into embryo