Seeds And Gymnosperms Flashcards
Seed
embryo and nutrients surrounded by a protective coat
What characteristics are common to all seed plants?
Reduced gametophytes,
heterospory,
ovules,
Pollen
What is an advantage of having reduced gametophytes?
They develop within parent sporophyte tissue. This protects it from environmental stress and allows it to obtain nutrients from sporophyte.
Heterospory
Seed plants are heterosporous
Where do spores develop?
Within sporangia born on modified leaves called sporophylls
Megasporophylls bear megasporangia that produce megaspores which form ______ gametophytes
female
Microsporophylls bear microsporangia that produce microspores which form ________ gametophytes
male
A _____ consists of a megaspore within a megasporangium surrounded by one or more protective coats (integuments)
Ovule
A male gametophyte enclosed within the pollen wall
pollen grain
Where do pollen grains germinate?
the female reproductive structure
A pollen grain produces a ______
pollen tube
The pollen tube grows into the ovule and discharge sperm into the ______ _______
female gametophyte
If sperm fertilizes the egg of a seed plant, the ___ grows into a sporophyte embryo
zygote
Seeds are ______
multicellular
Seeds can remain ____ for years until conditions are favorable for germination
Dormant
