Seedless Plants Flashcards
What supergroup is the plant kingdom in?
Archaeplastida Supergroup
What is the common ancestor of plants and protist?
A green algae from the group Charophytes
What characteristics do Charophytes and Plants share?
ring-shaped cellulose arrangement
flagellated sperm appear very similar
cell division patterns
sporopollenin polymer
Where did charophytes live and what did they have?
water’s edge
more unfiltered sunlight
more access to CO2
more nutrients due to erosion
What is sporopollenin?
a polymer that helped zygotes retain water, when they were exposed to dry conditions
What did sporopollenin help with?
terrestrial living
relative scarcity of water
lack of structural support
What four major divisions of plants are there?
seedless plants: non-vascular
seedless plants: vascular
seed plants: gymnosperms
seed plants: angiosperms
What is the alternation of generations?
life cycles of plants alternate between two generations of distinct multicellular organisms
What does haploid mean?
containing a single set of unpaired chromosomes (n)
What does diploid mean?
containing two complete sets of chromosomes, one from each parent (2n)
What are gametophytes?
haploid stage that can make gametes using mitosis (sperm and egg)
What are sporophytes?
diploid stage that makes spores using meiosis
What are the derived characteristics of plants?
alternation of generations multicellular walled spores in sporangia multicellular gametangia apical meristems cuticle and stomata
What do plant sporocytes make?
spores within multicellular structures called sporangia
What are spores covered in?
thick sporopollenin wall, resistant to harsh environments
What is gametangia?
multicellular organs dedicated to producing gametes
What is archegonia?
female organ, which makes one non-motile egg, and is this thus the site of fertilization
What is antheridia?
male organ, which makes motile sperm
What are apical meristems?
plants sustain continual growth from regions of constantly dividing stem cells that differentiate into tissues
What is the shoot meristem?
grows upward to increase light and CO2 exposure, often makes stems and leaves
What is the root meristem?
grows down, to acquire mineral nutrients
What is the cuticle?
a layer of wax, oil, or polymers to prevent water loss and protect against pathogens
What is stomata?
pores that allow for the exchange of gasses (O2 and CO2) and can be opened or closed to control evaporation
What clades are vascular seed plants divided into?
gymnosperms and angiosperms
What is a seed?
adaptive structures in which embryos are in a protective coat with a nutrient supply
What are gymnosperms?
the naked seed plants, which included conifers that often store seeds in cones
What are angiosperms?
flowering plants with seeds that are often housed within fruits
What are bryophytes?
non-vascular seedless plants
What are the three phyla of bryophytes?
liverworts
hornworts
mosses
What is the difference between the three phyla of bryophytes?
liverworts were first to evolve, don’t have stomata
hornworts and mosses posses stomata, more closely related to vascular plants
Since bryophytes don’t have “true roots”, what anchors them?
rhizoids
do not move nutrients or provide structural support
What is the dominant life stage of bryophytes?
haploid gametophyte
diploid sporophyte is present on females for short times
What are the two phyla of vascular seedless plants?
lycophytes (not true mosses)
monoliphytes (ferns)
What were vascular plants the first to do?
first plants to grow tall (tree size)
What allowed vascular plants to grow tall?
evolved vascular tissues
phloem: moves sugars, amino acids, and organic products
xylem: moves water and minerals through tubes of lignin polymer
Has true roots
has true leaves
What is the dominant life stage of vascular seedless plants?
diploid sporophyte stage
