Flashcards in Plantae Deck (55)
Alternation of generations (sporic life cycle)
both multicellular haploid and diploid generations, such that this life cycle is characterized by an alternation-of(multicellular haploid and diploid)-generations. This life cycle is an innovation of land plants.
produce male gametes (sperm cells).
Embryonic plant tissue in the tips of roots and in the buds of shoots that supplies cells for the plant to grow in length.
produce female gametes (egg cells). (adaptive value: retention of egg in archegonium provides protection for the zygote).
Bifacial vascular cambium
The bifacial vascular cambium of seed plants produces secondary xylem to the inside of the plant, and secondary phloem to the outside of the plant.
the female sex organ of flowering plants.
Chloroplast DNA inversion
The chloroplast DNA inversion happened in the ancestor of monilophytes and seed plants. It is when the DNA sequence in chloroplasts are reversed/inverted.
which nurture the sieve tube cells.
once a plant reaches a predetermined size, it will stop growing.
(2n) (of a cell or nucleus) containing two complete sets of chromosomes, one from each parent.
where each of the two sperm in a pollen grain fertilizes an egg.
multicellular and diploid; product of the mitotic division of the zygote
sexual structure of flowering plants
an expanded/ripened ovary.
the multicellular organs of the gameteophyte that produce gametes by mitosis (adaptive value: more gamete producing cells enable generation of more gametes per generation).
sexual haploid cells, typically eggs and sperm.
haploid ‘gamete plant’ that produces gametes by mitosis in gametangia.
(n); (of a cell or nucleus) having a single set of unpaired chromosomes.
(a sporic life cycle with two kinds of spores) evolved independently three times in vascular plants: a. in lycophytes, b. in leptosporangiate ferns, and c. in seed plants
Homospory - male and female gametangia may occur on each individual.
green sporophyte with indeterminate growth.
growing for its entire life time.
Cylinder of unspecialized meristem cells that divide laterally to give rise to cells that further divide and differentiate and specialize to form the secondary vascular tissue (secondary xylem and secondary phloem) Xylem tissue is produced on the inner side of the cambium ring and phloem tissue is produced on the outer side of the ring. There are two types of cambium layers: one that produces more vascular tissue, and the other that produces cork.
haploid female gametophyte.
(mega = big, phyll = leaf) are leaves with a many branched vascular strands that evolved from modified side branches in euphyllophytes. (“true” leaves with more complex vascularization derived from side branches).
(note that only one of the four megaspores survive; three of the megaspores experience apoptosis). The megaspore in turn undergoes three mitotic divisions to give rise to the female megagametophyte, the embryo sac.
cell division that results in a reduction of ploidy
meristematic cells are cells that have the ability to divide.
male heterosporous plant produce male gametes (sperm cells).