Exam 2 Flashcards
What is a tree?
A perennial woody plant, with a single main stem or trunk, and clear apical dominance
Are all trees seed plants?
Yes
What two Phyla do most trees fall into?
Coniferophyta
Anthophyta
What is wood?
A fibrous tissue composed of cellulose fibers embedded in a matrix of lignin.
What is wood produced by?
The secondary xylem in roots and shoots
What makes up wood?
Lignin
How many groups of fungi can decompose lignin?
Only one
What are trees two growth patterns?
Primary - elongation
Secondary - width
What is the heartwood of a tree?
Heartwood is older that sapwood and is usually darker because it has become infused with secondary chemicals
Heartwood is dead
What is the sapwood of a tree?
Sapwood is also dead and is responsible for transporting water and nutrients from roots to leaves
Both gymnosperms and angiosperms have xylem cells called?
Tracheids
What do gymnosperms not have?
vessel elements
What is the difference between tracheids and vessel elements
Tracheids - long and slender
Vessel elements - shorter and wider
When did land plants originate?
about 475 mya
When did vascular plants evolve?
about 420 mya
When did seed plants (gymnosperms and angiosperms) originate?
about 305 mya
The common ancestor of all land plants is?
Green Alga
List the 7 types of common land plants
Liverworts Hornworts Mosses Lycophytes Pterophytes Gymnosperms Angiosperms
Of the extant plant phyla, all woody plants are?
seed plants
All gymnosperm phyla have some woody representatives but most are in which phylum?
Coniferophyta
Conifer wood is called?
“softwood”
How many Ginkgo species are extant?
1
Amongst the angiosperms, all woody plants are?
dicots
Angiosperm wood is called?
“hardwood”
What does wood do?
Living wood transfers nutrients and water to leaves
Living and dead wood provide structural support
What two simple systems can all plants be divided into?
root and shoot systems
Components of the shoot system:
Flower
Leaf
Bud
Stem
Components of the root system:
Taproot
Fibrous root
Phloem conducts __ down the stem and is alive.
Sugars
Carbon fixation/sequestration are ___ ___ provided by trees
Ecosystem services
What was the FACE project mainly looking at?
To see what happens if you increase the amount of CO2 around trees.
What does FACE stand for?
Free-air concentration enrichment
Is wood really just air that has been chemically changes into its hard state?
Yes
___ and ___ are the main contributors to removing carbon from the atmosphere.
photosynthesis
oceans
Biogeochemistry looks at?
understanding the cycles of the earth
When did the FACE experiment start and what did is focus on?
1996
Focused on Loblolly pine trees that were exposed to CO2 concentrations one and a half times the ambient levels (the expected 2050 levels)
Did the CO2 enriched trees do better than the unenhanced?
Yes, for a little bit at least.
For about 7 years the enriched trees grew 10-25% faster than the unenhanced trees.
What plant loved the elevated CO2 levels and had 70% growth enhancement
Poison ivy - it grew super well and the samples has a lot more of the itching chemical
When did the FACE study end?
experiment was shut down in 2012
Why did the trees in the FACE study not grow as fast after 7 years?
Liebig’s Law of the minimum - plant can only grow as fast as the limiting resource.
What was the limiting resource in the FACE study?
Nitrogen
Trees were growing so fast that they sucked all of the nitrogen out and limited themselves
Loblolly pine can grow so fast that the apical meristem bends over - called a speed wobble and it forms a permanent bend in the tree.
Dust can carry what into the water systems?
Nitrogen
What mountains are nitrogen saturated?
Great Smokey Mountains
How do human’s fix nitrogen?
Haber process - puts nitrogen under pressure and combines it with hydrogen to produce ammonia
Also done through fossil fuel combustion
How does nature fix nitrogen?
Rhizobial (biological fixation)
Lightning
What is acid rain really not that big of an issue anymore?
Thanks to the clean air act - no more sulfur is allowed to be released from factories
(Legislation that actually did something)
How much nitrogen is fixed naturally in 1 year?
100Tg
How much nitrogen is fixed by humans in 1 year?
140Tg
Soil with a pH of 4.5 or lower ___ becomes mobile.
Aluminum
What was the acidity of US soil in the 1980’s?
4.7-5.4 pH
What was the acidity of US soil in 2002?
3.1-4.7 pH
What are the consequences of excess nitrogen?
Eutrophication in water
(only 1/3 of nitrogen is taken up by targeted crops)
Water is normally oligotrophic
Classification is?
the ordering of trees into groups that have common characteristics
What does classification seek to recognize?
The correct evolutionary lineage of organisms (their phylogenies)
Instead of “phylum” plant taxonomists call it this?
Division
In plants, it is also helpful to recognize sub- (under or beneath) and super- (over or above) classifications.
true
The basic unit of taxonomy and classification - it is the smallest unit at which individuals share phylogenetic features
Species
A ___ is any group of related organisms
taxon
What is the biological definition of species?
A group of organisms that can interbreed in nature
Do plants always listen to the biological definition?
No.
Plants often violate this assumption but we still recognize species in groups that hybridize
(Hybridization tends to be relatively common but most individuals have features that identify them as belonging to a particular species)
What are the 10 classification levels?
(D,K,Sub,Super,pD,C,O,F,G,S)
Domain Kingdom Subkingdom Superkingdom Phylum (Division) Class Order Family Genus Species
What are the first four levels of classification of all seed plants?
Domain = Eukarya Kingdom = Plantae Subkingdom = Tracheobionta Superkingdom = Spermatophyta
Classification began with this man?
Carolus Linneaus
He was Swedish
What was Linneaus’ system like?
His system was very simple and grouped some plants together in a way that, today, we would recognize as erroneous
He used characteristics of flowers like the number of stamens and pistils to indicate relatedness among plants
What did Linneaus’ system not take into account?
Convergent evolution.
Errors in classification arise from grouping organisms together based on homoplasises
What system do we use today to classify organisms?
Cladistics
Cladistics
The process of grouping organisms into clades.
The product is a cladogram.
Clade
a group of closely related species and their common ancestor
Cladogram
the product of utilizing cadistics
it is a diagram showing relatedness for the taxon in question
Parsomony
the cheapest
the simplest answer is probably the right one
To determine the ingroup of a clade you use this?
outgroup
Linneaus classified based on simple characteristics, what do today taxonomists used to determine relatedness?
Morphology Anatomy Cytology Palynology Chemistry of secondary compounds Ribosomal RNA DNA Enzymes to determine relatedness
Modern cladistics relies on these to produce cladograms.
very large databases and sophisticated computer programs
All cladograms are __ about the relatedness of the organisms in question.
Hypotheses
Can common or “familiar” names be used in scientific papers?
Yes, but because they vary widely by region, the scientific name must always be used to identify the species.
Common names are written in lower case except for proper names.
True
Common names often refer to:
Habitat Feature of the tree Locality Use Commemoration Adaptation from other language
The scientific name of any organism is binomial and written as?
Genus and specific epithet
What does it mean when a name is written as one word or has a hyphen?
That tree is named incorrectly
Typically it was realized later that it did not fit into that genus
Plants often have subspecies, varietals, or forms
True
In plants is it common to write the full or abbreviated name of the person or persons who originally published the plants name?
Yes it is
The name in the parentheses is always the original describer
Pinus jeffreyi (Grev. & Balf.) means
that both authors are equally responsible for the name
Pinus torreyana Parry ex Carr. means
that Parry used the binomial for this species but didn’t publish it
Carriere published the name but gave credit to Parry
Pinus edulis Englem. in Wisliz. means
that the name Engelmann used was published in a book by Wislizenus
The “___” in a any scientific name means that the plant is a hybrid
X
Intergeneric hybrids are noted with the x where?
X before the genus name
Cultivars are denoted with?
cv
Why do scientific names change?
Names change because of nomenclatural or taxonomic reasons
new information on the taxonomy on the genus
Division word endings consistently end in
ophyta
Class word endings consistently end in
opsida
Subclass word endings consistently end in
idea
Order word endings consistently end in
ales
Family word endings consistently end in
aceae
Groups of organisms that fit within a taxonomic category are often grouped with this suffix
“con”
Some taxa have only one species, for this the suffix ___ is used
“mono”
ex: Genus Ginkgo is monospecific
Knowledge of these three factors is not only interesting from an ecological stand point but it is helpful in identifying trees
Habitat
Range
Communities
All species are adapted to a range of environmental conditions
True
Is the adaptation of a tree to a specific range genetic?
Yes
What do we call the range a tree has adapted to?
“Niche”
Acclimatization
you get use to it
What is a niche?
A niche is the range of some number of environmental conditions to which an organism is adapted
What did Joseph Grinnell call a niche in the past?
The organisms “place” in it’s world
What did Charles Elton call a niche in the past?
The organisms “role” in it’s world
G. Evelyn Hutchinson defined the niche as an
“N-dimensional hypervolume”
Do species always occupy their entire niche?
no
The ___ niche is everywhere an organism could live in the absence of interspecific competitors
Fundamental
The ___ niche is everywhere it does live as a consequence of competitive outcomes with other species
realized
Joseph Connell did research on which two species?
Balanus (bullies)
Chthamalus
GF Gause proposed the idea of competitive exclusion. What is it?
That when the niches of two species overlap they would not coexist and one would competitively exclude the other.
(Interspecific competition)
Limiting similarity
There is a maximum level of niche overlap between two species that will allow them to coexist
Resource partitioning (“niche shift”)
Competing species utilize parts of the habitat in which that are most competitive
Character displacement
an evolutionary shift in behavior or physiology that results in niche partitioning
In any situation in which resources are too available, species will increase their niche space in order to utilize those resources - expand to their fundamental niche
true
If resources are limiting then competition will force those species back to their realized niche.
true
Climate
the regional interaction between solar radiation, the atmosphere and land and water masses
(not weather)
Soil
a living, three-dimensional substrate that provides water and most nutrient elements to trees
soil also provides support for the stem and crown of a tree
soil vary in texture, nutrient status, and age
dirt
soil where you don’t want it
Rain forest has old soil - farmers clear land and add nutrients with this method
slash and burn
soil only have nutrients for about 3-4 years
Physiography
slope elevation aspect land-shape land-water interface
Biota
all of the living organisms within an area
ecotone
region where the organisms present might start to shift due to environmental factors
endemic
native/restricted to an area
aspect
the direction a slope faces
North and east facing slopes stay ___ and ___ than do south and west facing slopes
cooler and moister
Temperature goes down and precipitation goes up as elevation increases
true
