Bio test 2 Flashcards
Plants are members of the eukaryotic supergroup ________ , and their closest relatives are _________.
Archaeplastida; charophyte green algae.
what characteristic is shared by algae and seed plants
chloroplasts
The closest algal relatives of land plants are __________
charophytes
Which of the following traits was most important in enabling the first plants to move onto land?
the development of sporopollenin to prevent the desiccation of zygotes
The diploid generation of the plant life cycle always __________.
produces spores
Which of the following statements correctly describes the colonization of terrestrial habitats by plants?
It occurred in conjunction with fungi that helped provide them with nutrients from the soil.
Which of the following characteristics of plants is absent in their closest relatives, the charophyte algae?
alternation of multicellular generations
sexual reproduction
cellulose in cell walls
chlorophyll b
alternation of multicellular generations
Which of the following organisms were most likely the direct ancestors of plants?
liverworts and mosses
kelp (brown alga) that formed large beds near the shorelines
photosynthesizing prokaryotes (cyanobacteria)
green algae
green algae
In plants, which of the following are produced by meiosis?
d/h mi/mei
haploid spores
About 450 million years ago, the terrestrial landscape on Earth would most likely have had which of the following features?
completely bare rock, with little pools that contained cyanobacteria and protists
tall forests in swamps
nonvascular, green plants similar to liverworts forming green mats on rock
flowers, grasses, shrubs, and trees
nonvascular, green plants similar to liverworts forming green mats on rock
Haploid of diploid?
gametophy
sporophyte
spore
zygote
H: Gameto + spore
D: Sporo + zygote
Which of the following assumptions led to the hypothesis that the first plants exhibited low, sprawling growth?
The ancestors of plants, green algae, lacked the structural support to stand erect in air.
Which of the following biological molecules contributes to the structural integrity of plant spores?
sporopollenin
Which of the following factors most likely helped early plants colonize land?
formation of mutualistic associations with fungi
Which of the following statements about the transition from ocean to land by plants is most likely to be accurate?
The transition to land occurred within a few generations.
Rising sea levels favored individuals that were able to survive ever-drier conditions.
The high light levels of terrestrial systems favored individuals that contained flexible photosynthetic enzyme systems.
The transition to land was likely gradual, with plants evolving traits that let them survive ever-drier conditions.
The transition to land was likely gradual, with plants evolving traits that let them survive ever-drier conditions.
In which of the following structures of a plant are apical meristems found?
shoots + roots
what do stomata do
Stomata allow gases to diffuse into and out of the plant.
The evolution of vascular tissue in plants facilitated which of the following changes?
the ability to grow taller
D or H: sporo and gamto
Sporophytes are diploid, whereas gametophytes are haploid.
Most bryophytes, such as mosses, differ from all other plants in that they _____.
lack true leaves and roots
In contrast to bryophytes, in vascular plants the dominant stage of the life cycle is the __________.
sporophyte
Which of the following characteristics is found in heterosporous plants?
2 type of sporophyll
Which of the following statements is correct regarding the structure of a fern?
sporangia are found on the sporophylls
Suppose an efficient conducting system evolved in a moss that could transport water and other materials as high as a tall tree. Which of the following statements about “trees” of such a species would be accurate?
Individuals would probably compete more effectively for access to light.
A life cycle that exhibits alternation of generations includes
multicellular haploid organisms and multicellular diploid organisms
In plants, the ________ produces haploid gametes (eggs and sperm) by mitosis, whereas the ________ produces haploid spores by meiosis.
gametophyte; sporophyte
When you look at a pine or maple tree, the plant you see is a __________.
diploid sporophyte
All seed plants _____.
are heterosporous
the adaptation that made possible the colonization of dry land environments by seed plants is most likely the result of the evolution of _____.
pollen
The major difference between angiosperms and gymnosperms comes from the __________.
presence or absence of a protective covering over the ovule
Which of the following is a major trend in land plant evolution over the past 200 million years?
the trend toward a sporophyte-dominated life cycle
Where in an angiosperm would you find a megasporangium?
within an ovule contained within an ovary of a flower
In seed plants, which of the following is part of a pollen grain and has a function most like that of the seed coat?
sporopollenin
Which of the following plant structures most directly produces the pollen tube of angiosperms?
male gametophyte
Which of the following functions is an advantage of seeds compared to spores?
containing a nutrient store for a developing sporophyte
Which of the following statements describes a difference between seed plants and ferns?
seed plants produce two kinds of spores
What are the products of meiosis in the life cycle of a seed plant?
Megaspores or microspores
In gymnosperms, megaspores develop into __________.
female gametophytes
In pine, the embryo develops within the ________
female gametophyte
Which of the following answers arranges the structures found on male pine trees from the largest structure to the smallest?
sporophyte, pollen cone, microsporangia, microspores, pollen nuclei
Which of the following generations in the conifer life cycle most directly produces the integument of a pine seed?
female sporophyte
Many types of plants produce fruit which is eaten by animals. The seeds of these plants are typically undigestible. Which of the following is an advantage for plants having undigestible seeds?
It allows the seeds to be dispersed into other areas.
Angiosperms are different from all other plants because only they have _____.
flowers
Unlike most angiosperms, grasses are pollinated by wind. As a consequence, some unnecessary parts of grass flowers have almost disappeared. Which of the following parts would you expect to be most reduced in a grass flower?
petals
Which of the following is a characteristic that distinguishes gymnosperms and angiosperms from other plants?
ovules
Many mammals have skins and mucous membranes that are sensitive to secretions of plants like poison oak. These secondary compounds are primarily adaptations that function in which of the following ways?
to inhibit herbivory
Immature seed cones of conifers are usually green before pollination, and flowers of grasses are inconspicuously colored. What does this indicate about how they are pollinated?
They are probably wind pollinated.
What type of cell division does the generative of a male angiosperm gametophyte cell undergo to produce sperm cells?
mitosis
Stamens, sepals, petals, carpels, and pinecone scales are types of which of the following structures?
modified leaves
Which of the following describes a difference between wind-pollinated angiosperms compared with animal pollinated plants? Wind pollenated plants ________.
produce much more pollen because winds disperse pollen randomly
Human survival depends on the produce of __________.
angiosperms (ag)
Which of the following statements are correct with regard to what physicians and pharmacists need to know about plants?
Land plants produce poisons and medicines.
Which of the following problems will likely increase if the human population continues to increase?
reduction in plant and animal diversity
A leaf would best be described as a
plant organ.
Root hairs are important to a plant because they _____
increase the surface area for absorption
Which of the following is correctly matched with its tissue system?
guard cells, with ground tissue
phloem, with epidermis
cortex, with ground tissue system
xylem, with ground tissue system
pith, with vascular tissue system
pith, with vascular tissue system
Which of the following plant parts absorbs most of the water and minerals taken up from the soil?
root hairs
Which of the following biological molecules is specific to woody sclerenchyma cells?
cellulose
starch
chlorophyll
lignin
lignin
Some understory plants in dense tropical rain forests have very large leaves. Which of the following is the most likely selective advantage of these leaves?
Increased leaf surface area maximizes light absorption for photosynthesis under low light intensity
Which of the following describes an anatomical difference between roots and leaves?
a waxy cuticle covers leaves but is absent from roots
Which of the following cell types retains the ability to undergo cell division?
a meristem cell near the root tip
How do cells in a meristem differ from cells in other types of plant tissue?
they continue to divide
In a meristematic region, the cell plate during mitosis is perpendicular to the side of the stem. In what direction will the stem grow?
vertically in height
Which of the following cells or tissues arise from lateral meristem activity?
secondary xylem
The primary growth of a plant adds __________, and secondary growth adds __________
height, thickness
Root apical meristems are found
in all roots.
You find a plant unfamiliar to you and observe that it has vascular bundles scattered throughout the stem cross section. What should you conclude about the plant?
It is a monocot.
A student examining leaf cross sections under a microscope finds many loosely packed cells with relatively thin cell walls. The cells have numerous chloroplasts. What type of cells are they?
parenchyma
what is the job of the epidermis In plant leaves
retention of water
Secondary growth never happens in
leaves
_____ provides cells for secondary growth.
Vascular cambium
Vascular cambium forms wood toward the stem’s _____ and secondary phloem toward the stem’s _____.
center, surface
What is the function of cork?
insulation and waterproofing
How is the supply of vascular cambium maintained?
y the division of cells
Cell division in the vascular cambium adds to the circumference of a tree trunk and the diameter of roots and stems by adding new __________ to the layer’s interior and __________ to the layer’s exterior.
xylem and phloem
The vascular cambium gives rise to
secondary xylem and phloem.
Additional vascular tissue produced as secondary growth in a root originates from which cells?
vascular cambium
Most of the growth of a plant body is the result of
cell elongation.
Plants and animals respond differently to the environment. Which statement most accurately compares the responses of plants and animals to changes in their environment?
Animals tend to respond to changes in their environment by movement; plants tend to respond to changes in their environment by growth.
The diffusion of free water across a selectively permeable membrane is called
osmosis
Which of the following is an end product of photosynthesis?
glucose
Plants must always compromise between maximizing __________ and minimizing __________.
photosynthesis, water loss
Mycorrhizae are _____.
mutualistic associations between plant roots and fungi
A student is performing a chemical analysis of xylem sap. This student should not expect to find much _____.
sugar
Which of the following accurately describes the direction phloem sap can flow?
from leaves to roots or roots to leaves
A plant developed a mineral deficiency after being treated with a fungicide. What is the most probable cause of the deficiency?
Mycorrhizal fungi were killed.
Photosynthesis ceases when leaves wilt, mainly because
stomata close, preventing CO 2 from entering the leaf.
What would enhance water uptake by a plant cell?
positive pressure on the surrounding solution
Which of the following terms describes the physical property that predicts the direction of water flow in plants?
water potential
water potential
water and solutes move out of one cell, across the cell wall, and into the neighboring cell
How does the same cell differ if it is a flaccid cell compared to a turgid cell?
The flaccid cell has lower pressure potential.
Compared to a cell with few aquaporins in its membrane, a cell containing many aquaporins will have which of the following?
a faster rate of osmosis
If you place a flaccid plant cell in pure water, which of the following will occur?
Water enters the cell because the flaccid cell has solutes and low water potential.
Which of the following defines the loss of water from the aerial parts of plants?
Which of the following defines the loss of water from the aerial parts of plants?
Most of the water absorbed by a plant is used for what purpose
to replace water lost during transpiration
Which process provides the main force driving water within xylem vessels?
evaporation of water through stoma
Which one of the following refers to the loss of water through the stomata in a plant’s leaves?
transpiration
Which of the following would tend to increase transpiration?
higher stomatal density
Which of the following is a result of the high surface-to-volume ratio of leaves?
increased CO Subscript 2 absorption
Which of the following best explains decreased photosynthesis in wilted leaves?
stomata close, preventing carbon dioxide from entering the leaf
What is the advantage of having small, needlelike leaves?
decreased transpiration rate
Plants adapted to arid environments are described as which of the following?
xerophytes
The solute most abundant in phloem sap is _____.
sugar
Essential elements are those
required by living organisms to complete their life cycle and reproduce.
An example of a mutualism would be
vitamin-producing bacteria that feed off food remnants in the guts of humans.
Topsoil _____
is a mixture of rock fragments, living organisms, and humus
The inorganic nutrient most often lacking in crops is __________
nitrogen
A group of ten tomato plants are germinated and maintained in a large tray with no drainage. After several weeks they all begin to wilt and die despite repeated watering and fertilization. Which of the following is the most likely cause of the plant death?
a lack of oxygen for the roots
Which of the following properties is least conducive to plant growth?
high cation exchange capacity
compacted soil
abundant humus
numerous soil organisms
compacted soil
Which of the following soil minerals is most likely leached away by a hard rain?
NO3-
What does the N-P-K ratio on a package of fertilizer indicate?
percentages of three important mineral nutrients
Which of the following soil conditions would inhibit the growth of most plants?
absence of an A horizon
How do plants obtain organic molecules?
Plants synthesize their own organic molecules
For an element to be considered a macronutrient _______
it must be required in relatively large amounts
Which of the following experiments is the best way to determine if an element is essential for plant growth?
Grow a plant using hydroponics with and without the element.
Which criteria allow biologists to classify chemicals into macronutrients and micronutrients?
the quantities of each required by plants
Which elements are most often the limiting nutrients for plant growth?
nitrogen, potassium, phosphorus
Nitrogen-fixing bacteria in the soil __________.
convert atmospheric nitrogen to ammonia
Do nitrogen fixing bacteria converte nitrate to ammonium or ammonia
ammonia
The relationship between legumes and Rhizobium is __________.
mutualistic
Mutualistic associations between roots and soil fungi are called _____.
mycorrhizae
Epiphytes are
plants that grow on other plants.
Which of the following best describes the process of nitrogen fixation?
converts nitrogen gas into ammonia
Which of the following best describes epiphytes?
plants that grow on other plants but do not obtain nutrients from their hosts
While hiking in a forest, you notice an unusual plant growing on the branches of a tree. Which of the following criteria will best will help you to determine if this plant is epiphytic or parasitic?
The roots of a parasitic plant will penetrate through the bark into the xylem.
growing taller allows plants to
outcompete their neighboring plants
Most plants are _______ bc they can generate their own food via
photoautotrough, photosynthesis,
Which transport pathway is found external to the plasma membrane
apoplast
_______ predicts the direction of water flower
water potential
what 2 materials are heavily involved in a component of DNA/RNA of plants
Phosphorus and Nitrogen
most productive soils are negatively charged. how does this affect anions/cations found in soil
anions can easily be leacahe dbc they cannot bind to the neg charged particles
which 2 mechanisms led to sedentary ag
fertilization + crop rotation
Thaspi caerulescen is valuble bc it
accumulates large amonts of ZINC
which what are the 6 major macronutrients
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur,
_________ is a durable polymer that allowed algae to live above waterlines by
preventing zygotes
sporopollen
___________ are multicellular organs of a sporophyte in plants. These
structures produce spores
sporingia
Phylum Anthocerophyta refers to a plant group called the ____________
hornworts
A pine cone is an example of a ___________
strobilus
What life cycle is best represented in plants?
sporic meosis
the ovule is composed of
Megasporangium
Megaspore
Integument
Which of the following correctly describes the similarities and differences
between seeds and spores
Seeds are unicellular, whereas the spores are multicellular.
Seeds contain nutrients within them, whereas the spores do not.
Seeds are generally smaller than spores.
Neither are equipped with structures to withstand stressful environments
Seeds contain nutrients within them, whereas the spores do not
Stamens produce ____________ on a flowe
pollen
Which group of plants exhibits gametophytes that are completely dependent on
the larger sporophyte?
gymnosperms
____________ represent around 90% of all plants on Earth.
angiosperms
In conifers, ____________ produce male spores, and ____________ produce
female spores
microsporangia; megasporangia
Which are the sterile organs of a flower?
sepals and petals
___________ transports sugars and photosynthates in both upward and
downward directions in a plant
Phloems
Xylem and phloem made it possible for the development of extensive root and
shoot systems because they perform ____________
long-distance transport
Nitrifying bacteria can…
a. Convert ammonium to nitrite
b. Convert nitrite to nitrate
c. Convert nitrogenous gas into ammonia
d. Only A & B
e. Only A & C
a. Convert ammonium to nitrite
b. Convert nitrite to nitrate
What is referred to as the “organic layer” of soil?
humus
Which of the following is a parasitic plant that we discussed in class?
a. Pitcher plants
b. Venus fly trap
c. Mistletoe
d. Staghorn ferns
Mistletoe
Which of the following DOES NOT serve as a stimulus for stomatal
opening/closing?
a. Carbon dioxide
b. Cellulose
c. Light
d. Guard cells “internal clock”
cellulose
branched stem will have to produce ____________ energy for efficient
photosynthetic processes (when compared to a less-branched stem).
a. Less
b. More
more
Unlike humans, most plants can grow during their lifetime due to
_______________
indeterminate growth
Because plants have parenchyma cells, collenchyma cells, and sclerenchyma
cells, you can describe plants as being ____________.
a. Multicellular
b. Asexual
c. Unicellular
d. Tendrils
multicellular
what has inhabited earth for longer, plants or prokaryotes?
prokaryotes
charophyte algae are known to ave inhabited shallow waters/edges of ponds and lakes. what was an issue they may have faced
drying during drought
moving from aquatic enviro to terretrial provided plants with what 3 advantages
more sun, more CO2, more minerals in soil
one of the unique structures found in plants compared to charophytes is stomata which does____
exchange of respiratory gases
which of the following phyla would have dominant sporopyte:
hepato, anthocero, lyco, bryophyta
lycophytes
reduced gametophyte size observed in vasc plants suggest bigger sporophytes which does these 3 things
protect from UV
provide protection from drying
provide nutrition to gametophytes
seed plants are heterosporous and have mega/microsporangia. what is produced in the megasporangia and what is the sex
megaspores; female
what do coniferophyta species do to make up for the smaller leaf size
stay evergreen to perform photosynthesis year round
what is the male repro organ in angiosperms
stamen
what are the 2 funtions of fruits
protection and dispersal
Green alage is in supergroup _______ and includes 2 types:
Archaeplasta: chloro/charopytes
______ are protists who are the most similar to land plants
charophytes
what keeps plant spores from drying out, allowing plants to live on land (Derived from charophytes)
sporopollenin
what are 3 benefits of moving out of water
Bright, direct light
more co2
rich in minerals
downside to living outside of water
lack of support against gravity
One main difference between charophyte an plants is its ________ life cycle with dominant _______
Alternation of generations
sporophytes
what is different btw the sporinga of charophytes and plants
plants have walled sporinga that is protected by sporopollenin
what are apicla meristems
localized regions of cell division at the tips of roots and shoots
can continuously divide
What is the cuticle
Waterproof covering on epidermis of plant speices to prevent water loss and microbial invaders
5 main adaptations of charophytes and plants
alternation of generations
walled spores in sporinga
apical meristems
cuticles
stomata
what is vascular tissure
cells joined into tubes to transport water and nutrients thru the plant
What is the example of nonvasc plants
bryophytes
3 kinds of bryophytes
Hepatophyta (liverworts)
bryophyta (moss)
anthocerophyta (hornworts)
sporangium
splits open and releases mature spores at tip
In vasc plants ______ are larger and more complex
sporophytes
Xylem
Phloem
X: Carres most of water + minerals (flows up)
P: carries sugar, amino, organic products (bidirectional)
Microphylls
small, spire shaped leaves supported by a single strand of vasc tissure
megaphylls
highly branched vasc system, greater photosynthetic, greater photosynthesic productivity than microphylls
which has better photosynthetic productivity micro or megaphylls
megaphhylls
sporophylls
modified leaves that hold sporangia
sori
clusters of sporangia in ferns
strobili
cone-like structure (gymnosperms)
most seedless vasc plants are _____sporous
homo (gametophyte makes egg and sperm)
vasc plants are usually ________sporous
hetero
Sporophylls make spores
sporophylls make spores
what is a seed
embryonic stage of a plant life cycle
packaged w a supply of nutrients and
Mosses and other bryophytes’ life cycles were dominated by
__________
* Ferns and other seedless vascular plants have _______-dominated
life cycles
gameto
sporo
are the gametophyts visible to the naked eye in gametophytes? sporophytes
yes; no
seed producing plants are ________ dominated
sporophyte
which is bigger in seed plants: sporophyte or gaetophyte
what do they provide for eachother
Sporophyte is bigger (and
can protect the gametophyte
from UV radiation and
drying)
* Gametophyte can obtain
nutrients from “parental
sporophyte
Gametophytes of seedless
vascular plants are
___________ (independent/dependent)
independent
seedless plants are _____sporoous
seed producing plants are ______ sporous
homo
heter
Ovules
develops within the ovary of a seed plant and contains the female gametophyte
Megasporangium + megaspore+ integument
Seed plants ________ megasporangium
retain
Pollen
male gametophyte enclosed within the pollen wall made of sporopollenin
Pollination
germination
P: transfer of pollen to part of a seed plant containing ovules
G: when pollen starts to grow into a pollen tube that is able to discharge sperm into female gametophyte
In non-vasc plnants, gametophytes release _______ sperm that swim through ________
flagellated
film of water to reach eggs
What are pine trees and cones relative to gametophyte and sporophyte
sporo= pinetree
gameto-= come
conifers are _____sporous
heter
In gymnoposerms, within each __________,
_____________ undergo meiosis,
producing haploid ____________
microsporangium, microsporocytes
microspores
4 phylum of gymnosperms
Cycadophyta, ginkgophyta, coniferophyta, Gnetophyta
Large cones + palm like leaves
flagellated sperm
most endangered gymnosperm
Cycadophyta
Flagellated
deciduoius, fanlike leaves
ginkgophyta
Example of gnetophyta?
welwitschia
can live for 1000+ years
straplike leaves (largest leaves known)
are coniferophyta cones woody or fleshy
mostly woody but can be fleshy
all angiosperms are in phylum ______–
antophyta
flowers are used for ____________
sexual reproduction via animals or wind
Parts of flower (modified leaves) (in order from out in)
Sepal: green and enclose flower
petal: usually bright colored
stamen: male, pollen producing
carpels: female, holds seeds
what 2 flower organs are sterile
sepals and petals
2 parts of stamen
filament: stalk
anther: terminal sac where pollen forms
parts of carpel
stigma: sticky part to recieve pollen
style: stalk
Ovary: egg container
Pistil: group of carpel
cross-pollination
transfer of pollen from anther to stigma of another flower
Cotyledons
seed leaf of angio embryo
monocot: 1 cot
dicots (eudicots): 2 cots
roots function
anchor in soil and absorb/transport minerals and water
store food
in seed embryo, the ______________ first emerges
primary root
Tall, erect plants with larger shoot usually have the _____ system
taproot
root hairs
thin, finger like extensions of root epidermal cells that emerge and increase the surface area of the root
form mycrrhizal associations
The absorption of water and
minerals usually occurs primarily
_________________________
near the tips of roots (where vast
numbers of root hairs are found)
Apical bud –
Axillary bud –
Ap: bud at the tip of a
plant stem
Ax: found in the
angle between a leaf and stem
(can become a branch)
pats of vasc plants
Blade – flattened portion of leaf
Petiole – stalk that joins the leaf
to the stem at a node
Veins – vascular tissue
Ev adaptations of leaves
Tendrils – “curl” for support and
attachment
Spines – help plants survive in hot/dry environments AND defense mechanism
Reproductive leaves – can fall off the plant and take root in the soil!
Storage leaves – modified leaves that store food
3 types of plant tissue
dermal, vasc, ground
Dermal tissue
outer protective covering of plant
first line of defense
includes cuticle
Guard cells
trichomes
type of tissue?
dermal tissue
Guard cells – involved in gas exchange
Trichomes – hairlike
outgrowth on a plant shoot
can reduce water loss and
reflect excess light
Vasc tissue
transports materials machanical support
includes xylem + phloem
ground tissue
everything not dermal/vasc
Pith and cortex
type of tissue?
Ground tissue
Pith – ground tissue internal to vascular tissue
Cortex – ground tissue external to vascular tissuew
hat does cell differentiation do? 3 kinds
creates specialized cells
parenchyma, collenchyma, sclerenchyma
what tissue is resposible for photosynthesis, gass exchange,, and storing water and nuttrients
parenchyma
what tissue is mechanical support and elasticity
collenchyma
plants can keep growing bc of the ________
meristems: structures that remain embryotic their entire life and continue to grow (on ends of root and shoot)
have indertminate growth
Apical meristems
located at root and shoot tips; enable primary growth
Apical meristems produce 3 types of primary meristems:
Protoderm → dermal tissue (epidermis)
Ground meristem → ground tissue (photosynthesis, storage, & support)
Procambium → vascular tissue (xylem & phloem; transport)
Root cap –
cone of cells at the
tip of apical meristem that
serve as protection
Leaves develop from __________
leaf primordia (finger-like
projection that emerges on
sides of shoot dapical
meristem)
direction of primary vs secondary growth
prim=up
2nd= out
2 lateral meristems
vascular cambium
cork cambium
vasc cambium
lateral growth
creates tree ring patterns
cork combium
makes cork and suberin (hydrophobic)
Bark
all tissues external to
vascular cambium
difference btw cork and bark
Bark = protective
outer layer that
includes cork
Cork = outer layer of
bark (a part of bark)
Self-pruning –
nonproductive
leaves or branches undergo programmed cell death
usually looses lower branches that cant get as much sun
plants can ________ adjust their roots to exploit patches of nutrients
quickly
what connects buffalo grass mother/daug cells
stolen
2 major pathways for water/nutrients
Apoplast – everything external to the plasma membrane of a
plant cell (outside cell)
Symplast – continuum of
cytosol connected by
plasmodesmata between cell (inside cell, includes transmembrane route)
Osmosis
the diffusion of free* water across a membrane
water potential
predicts the direction
in which water will flow
move from high water
potential (low solute) → low water potential (high solute)
turgid vs flaccid
wilting
t: firm
f: limp
w: loss of turgor over
time (stems droop as a result of cells losing water)
Transpiration
the process which moisture (water) is carried through the tree from roots →
stomata
stomata is controlled by ____
guard cells
stimuli for stomata
light, co2, internal clock (open during day)
Xerophytes
plants adapted to
arid (dry) environments
shorter life cycles and quickly germinate and bloom
fleshy stems and reduced leaves w stomata closed during the day
What cacti has white hairlike bristiles that reflect sunlight
cephalocereus senilis (old man catcus)
Bulk flow
the movement
of a fluid due to a difference
in pressure between 2
locations
independent of solute
xylem + phloem
What is resposible for transipration and transduction
ration: xylem
duction: phloem
what chemials are in fertilizers
Nitrogen, phosphorous, potassium (NPK)
what is NPK used for in plants
N: DNA/RNA, protiens, chlorophyll
P: Dna/RNA, ATP, phospholipids
K:contactor enzymes
plants absorb water + minerals from the _________ layer of the soil
upper layer
Humus
organic layer
make of dead orgs, and other organic matter, makes topsoil
prevents soil packing
topsoil + other soil layers are called
soil horizon
What horizon is topsoil
horizon A
Are productive soils made of - or + particles
- (anions) bc they allow for leachingl
leaching
percolation of water through soil
what is NPK ratio
Nitro+Phos+Potassium ratio in fertilizers
plants prefer _________ soil, if the ph is to low, it ___________
slightly acidic
low prevents root growth and uptake of calcium (serious problem in tropics)
phytoremediation
Nondestructive biotechnology that takes advantage of some plant
species’ abilities to extract heavy metals/other pollutants from the soil
and concentrate them in easily harvested portions of the plan
____________ can
accumulate zinc 300x higher than
most plants can tolerate
Thlaspi caerulescens
Hydroponic cultures
plants grown in mineral solutions instead of soil
* Used to determine which
elements are essential!
Is potassium a major component
no
Macronutrients
plants
require them in large amounts
6 major components
Carbon
* Hydrogen
* Nitrogen
* Oxygen
* Phosphorous
* Sulfur
(CHNOPS)
Micronutrients
Needed in small quantities
sodium
example of plant-animal relation
ants provide protection and plant provides food
example of plant-bac relation
plant provides carbs
bac makes Nitro and protects via antibody(Rhizobacteria)
Rhizobacteria
bacteria that live either in close association with plant roots (the rhizosphere)
or with closely surrounding plant roots
depends on sugar and amino from plant
Nitro fix
why is nitro fixing important
plants cant get enough from leaching since it is a macronutrience so most of N comes from bac
Plant roots can absorb N____ and N______
NO3
NH4
Nitrogen cycle
series of steps where nitrogen-containing
substances from the air and soil are made available to living things, used by them, and returned back to the air and soil
Nitrogen-fixing bacteria steps
Capture N2from atmosphere -> Reduce to NH3 (ammonia) -> gains H from soil -> NH4 (ammonium)
what does nitrifying bac do
Oxidize NH4 (ammonium(+ → NO2 (nitrite)
* Oxidize NO2(nitrite) → NO3(nitrate)
Denitrifying bacteria
NO3- → N2 → atmosphere
Epiphytes
Plant that grows on another plant
* Produce and gather their own nutrients; do not tap into the host
