Exam 1 Review Flashcards
What is a plant?
it has flagella, starch, and chlorophyll
What is taxonomy?
classification and nomenclature
What is systematics?
taxonomy and phylogeny
What is the difference between taxonomy and systematics?
systematics is more concerned with evolutionary history and diversification of species (through the lens of phylogeny) and taxonomy is more concerned with nomenclature and arranging species based on characteristics
What are the goals of plant taxonomy?
- Description
- Identification
- Nomenclature
- Classification
- Phylogeny
Utilitarian classification
based on how the plants are used, can change over time
Cladistics/Phylogenetics
species form lineages of related organisms, assume similarities in closely related groups are due to common ancestry
What is a species?
a basic grouping of organisms
How are species formed?
speciation- isolation of populations, divergence in traits, reproductive isolation
What are the forces of evolution?
mutation, gene flow/migration, genetic drift, natural selection
What is nomenclature?
giving names to taxa
What are the scientific naming conventions in botany?
binomical nomenclature: genus + specific epithet
How can we use herbaria?
document variation, ecological info, genetic info, chemical composition,
What are the characters shared between all green plants?
chlorophyll, flagella, starch
What is the closest relative to land plants?
green algae
stomata are shared by _________
mosses, hornworts, and vascular plants
What are the challenges of land for plants?
resource availability, reproduction challenges, water availability, unstable climates/ environmental stress, light availability and intensity, competition, herbivory
What are the characteristic traits of non-vascular plants?
- multicellular sporophyte
- embryo
- gametangia
- sporangium
- cuticle
What are the characteristic traits of vascular plants?
- vascular tissue
- xylem with tracheids
- lignin
- elaborated and dominant sporophyte stage
- reduced gametophyte stage
How is bark produced?
the vascular cambium
How is wood produced?
from the secondary xylem, wood is everything from the vascular cambium in
When did heterospory evolve?
Once in the lycophytes, then again in spermatophytes
When did seeds evolve?
370 MYA
What are the characteristic traits of gymnosperms?
- wood and cambium
- periderm (outer layer of bark) production via cork cambium
- axillary branching
- heterospory
- seeds
What are the components of a seed?
seed coat (integument), nutritive tissue, embryo
Which order had both conifer and angiosperm characters? What are they?
- Gnetales
- confier character: seeds not enclosed in an ovary
- angiosperm characters: wood vessels, double fertilization, flower-like structures
What are the characteristic traits of angiosperms?
- diverse, monopyletic lineage
- whole genome duplication (polyploidy)
- flowers
- reduced male and female gametophytes
- double fert
- xylem and phloem
What is a flower?
reproductive structure
Natural Classification
related plants are grouped together by some trait, based on individual experience, each character has the same weight
Characters/traits used in phylogenetics
morphological, anatomical, chemical, molecular, life history traits
homologous structure
common origin, different function (ex: leaves)
analagous structure
similar function, different origin (ex: sweet potatoes and potatoes)
molecular systematics
the use of DNA or RNA to study the phylogenetic relationships among organisms
what are the 3 genomes in a plant cell?
chloroplast, mitochondrion, nucleus
What are the methods of making trees?
algorithmic method and optimality criterion
biological species concept
members of a populations can interbreed in nature and produce fertile offspring
taxonomic/phenetic species concept
overall phenotypic similarities and these organisms look different from others
ecological species concept
members of a population occupy the same niche or habitat
what is evolution?
descent with modification, change in allele frequency
what are the advantages of alternation of generations?
increased spore production allows more spores than a single zygote, being diploid prevents expression of deleterious genes and increases diversity
What is oogamy and when did it arise?
retention of egg cells, starts in the bryophytes
antheridium
male gametangium containing sperm cells
archegonium
female gametangium containing the egg
What is the defining feature of liverworts?
gemma cups for asexual reproduction
Xylem
- transports water and minerals
- lignified cell walls for sturcture
- dead at maturity
Phloem
- transports sugars from leaves
- cells are alive, but with companion cells that store the nucleus
Purpose of lignified secondary cell walls
increase rigidity, waterproof, don’t rot easily
Bryophytes don’t have roots, they have __________
rhizoids
What ploidy are sporophytes?
2n
Lycophytes
- “fern allies”
- dichotomously branching root systems
- microphylls
- heterospory
Pseudomonopodial growth
main axis and side branches, sporangia on the end of lateral branches
Euphylls
megaphylls formed from flattened branches, has a leaf gap of interrupted vascular tissue
What traits are special about the Psilotaceae family?
no roots, 2 or 3 lobed sporangia
What are sporophores and what family are they found in?
distinct part of the leaf that produce sporangia (squidward hands), Ophioglossaceae
What traits are special about the Equistaceae family?
whorled leaves, hollowed stem
rhizome
horizontal stem that runs underground
Characteristics of leptosporangiate ferns
- rhizome
- leaves called fronds
- sori with indusia
What does a leptosporangium do?
flings out mature spores
Sori
clusters of leptosporangium
indusium
covering for sori
Eustele
vascular bundle arrangement in the stems
Sclerenchyma
cells with lignified secondary cells walls, provide support, dead at maturity, fond in xylem, wood, bark, and seed coat
vascular cambium
produces secondary xylem inside (more) and secondary phloem on the outside
cork cambium
special cells that differentiate into cork
cork
water resistant, think layer of cells protect the delicate vascular cambium and secondary phloem
axillary branching
new shoots can emerge from the axillary buds
components of a seed
seed coat, nutritive tissue, embryo
what is the nutritive tissue in a seed made of?
the tissue of the female gametophyte
micropyle
an opening in the megasporangium that secretes accepts pollen, and secretes a pollination droplet in some cases
Corraloid roots with N fixing bacteria can be found in _____________.
cycadophytes
What are cones?
a way of housing spores, modified leaves
what are the 5 derived traits of seed plants?
seeds, reduced gametophyte, ovule, heterospory, pollen
stamen
modified leaf with microsporangia
carpel
modified conduplicate leaf with ovules
androecium
- stamen with filament and anther
- microsporangia
gynoecium
- carpel with ovary that encloses ovule
- elongated style
- stigma recieves pollen
ovule
organ that forms seeds, megagametophyte
Angiosperm vessels
- xylem with perforation plates that stack, more efficient than tracheids
- more complex phloem with sieve plates
Complete flower
androecium + gynoecium + perianth
incomplete flower
missing one or more element of a complete flower
bisexual/ perfect flower
has the androecium and gynoecium
unisexual/ imperfect flower
only one reproductive structure (androecium or gynoecium)
