Download Chapter 29 – How Plants Colonized Land

Chapter 29 – How Plants Colonized Land
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Four main groups of land plants:
o ________________________ (mosses)
o ________________________ (ferns)
o ________________________ (conifers – ex. pines)
o ________________________ (flowering plants)
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Bryophytes → “_____________________”; (no water tubes)
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Pteridophytes → “___________________” but _______________________
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Gymnosperms → “__________________” with ______________
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Angiosperms → “___________________” with ______________________________________
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Closest relative to land plants = green algae called ________________________
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Features of Land Plants:
o
o
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BUT….many algae have some of this….SO…
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UNIQUE FEATURES connect land plants and charophyceans:
o
o
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Differences between land plants and close algae relatives (so ONLY land plants have these):
o __________________ meristems
o ______________________ embryos
o ___________________ of generations
o Sporangia produces ______________________
o Gametangia produces gametes

Archegonia =

Antheridia =
o DETAILS →
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Apical meristems →

Multicellular, dependent, embryos →
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Alternation of generations →

Gametophyte with haploid cells → gametophyte produces …


Sporophyte with diploid cells → sporophyte is produced by mitotic division of
the _______________________; sporophyte produces haploid spores by
____________________
o ALSO…..water conservation →

Prevents desiccation

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Except for bryophytes, land plants all have true roots, stems, leaves because of vascular tissues
o Xylem →
o Phloem →
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Evolutionary connections between land plants and charophyceans:
o Homologous chloroplasts, peroxisomes, cell walls
o ________________________ (structure in cell division)
o _______________________ sperm (algae and many plants)
o Molecular systematic → chloroplast DNA and rRNA
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Bryophytes
o Three phyla: __________________________, ____________________________,
_______________________________ (mosses closest to vascular plants)
o ____________________________ most conspicuous/ dominant phase


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Vascular Plants
o Food transport (__________________) and water transport (___________________)
o
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o ___________________________ = dominant generation

Pteridophytes (seedless vascular) → FERNS

Sporophyte = dominant
o Homosporous →
o Heterosporous → 2 kinds of spores

-

Megaspores =

Microspores =
Produces sori →
Other information:
o Seedless vascular plants formed “__________________” during carboniferous period

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Chapter 30 – Evolution of Seed Plants
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Reproductive Adaptations of Seed Plants:
o Reduction of gametophyte


NOT ________________________ like in pterophyta (ferns)
o Evolution of seed
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Spores →

Seeds →
o Evolution of Pollen
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
Pollen →

No water requirement (no flagellated sperm)
Seed Plants
o Vascular plants that produce seeds
o Recall: sporophyte = dominant phase (ex. pine trees = sporophytes)
o Two clades of seed plants:

Gymnosperms →

Angiosperms →

Most diverse and geographically widespread

_________________ known species
o ANGIOSPERMS = phylum ___________________________
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Monocots →
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Leaves with ______________________ veins
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______________________ group (single ancestor)


Dicots →

Leaves with _________________________ veins


_____________ seed leaves
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
Success of angiosperms due to:



Flowers:

Angiosperm structure specialized for reproduction
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Specialized shoot with 4 circles of modified leaves: sepals, petals, stamens,
carpals
o Sepals →
_____________ and
____________ are
NOT involved in
reproduction
o Petals →
o Stamens →

Produce _______________________ → male gametophytes

o Carpals →

Also called ________________
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Produce __________________________ → female gametophytes
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Stigma →
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Style →
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Ovary →

Ovules/ seeds are protected by the ovary
o Seed forms from _________________
o Fruit forms from ________________
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Fruit:
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Angiosperm structure that protects dormant seeds and aids in dispersal

Mature ovary (fruit)
o
o Wall of ovary becomes a ______________________ →

Simple fruit →
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
Aggregate fruit →
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Multiple fruit →
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Humans produce edible fruits via selective breeding (ex. apple, orange, cereal
grain)
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Angiosperm Life Cycle

Heterosporous →
o Male →
o Female →

Steps of the cycle:
o Anthers produce microspores
o Microspores form pollen
Male
o Ovules produce megaspores
o Megaspores from embryo sac
Female
o Pollen → sticky stigma of carpal
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Although they can self pollinate, most ____________________________
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Cotyledons →
Double Fertilization

Characteristic of angiosperms

Creates _______________________ central cell

Function→
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Specifics →
o 1 pollen grain = __ sperm
o 1 sperm fertilizes the egg → ___ zygote
o 1 sperm fuses with the 2 nuclei to form 3n __________________ which
becomes the …

Note→
o Monocots store most food in __________________________ (ex. corn)
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o Dicots transfer nutrients from the endosperm to the
_____________________ (ex. beans)
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Coevolution

Relationship between animals and angiosperms
o
o
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Plants and Human Welfare

Agriculture (food!) is based on ________________________

Plant diversity is non-renewable
o Humans are extinguishing plants →
o Ethical concerns →
o Practical concerns →

ECOSYSTEMS ARE LIVING TREASURES!!
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Chapter 35 – Plant Structure and Growth
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Angiosperms → 250,000 species; most diverse and widespread
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Genes and Environment affect Structure
o Long-term –
o Short-term –
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Ex.
Plant Organs: roots, stems, leaves
o Differences between monocots and dicots
MONOCOTS
DICOTS
Embryos
Leaf Venation
Stems
Roots
Flowers
o Resources are needed from soil AND air; therefore, we need:

___________ system

___________ system
***These two depend on each other ***
o Roots → Function →
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Monocots =

Dicots =

Both may have ______________________ (increase surface area; take up much water)
OR __________________________ (above ground) roots
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o Shoots →
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________________________ (leaf)
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________________________ (flower)
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Modified shoots (tubers, bulbs, etc) can be mistaken for roots
o Stem →
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_____________________ bud (angle at leaf/ stem) have potential to bud
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_________________________ bud – concentrated growth; this inhibits axillary buds →
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However, if terminal bud is removed (pruning) the axillary bud will start to grow
o Leaves →
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Structure →
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Some have special functions (pg. 724)
Plant Tissues → Dermal, vascular, ground
o Dermal –
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o Vascular –
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Transports between roots and shoots
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Xylem →

o Tracheids →
o Vessel elements →
o Fig. 35.8 pg. 725
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Phloem →

o Sucrose and other organic molecules thru tubes formed by chains of cells
→ _______________________________ elements
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End → sieve plates that have pores
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Non-conducting ____________________________________
may assist (via plasmodesmata)
o Ground –
-
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Neither dermal nor vascular
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Function →
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In dicots, divided as:
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Pith →
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Cortex →
Plant Cells → parenchyma, collenchyma, and sclerenchyma
o 3 basic types of cells

Each cell has structural adaptations in the protoplast (contents) or cell wall

Plasmodesmata →
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Middle Lamella →
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Primary Wall →
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Secondary Wall →
o Parenchyma
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Primary walls →
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Most lack ____________________________ walls
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“Typical Cell” → therefore they are the __________________ specialized (all cells start
out as parenchyma)
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PHOTOSYNTHETIC!
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Perform most metabolic functions
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Division →
o Collenchyma
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Primary cell walls →
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Grouped together to support ______________________________________________
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Lack __________________________ walls
o Sclerenchyma
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Function as ____________________________________ in plants
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Thick ________________________________ walls with ____________________
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More rigid than collenchyma
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Mature cells cannot elongate, so they are present in cells that have ________________
_________________________
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Plant Growth and Development
o Major differences between plants and animals:
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Totipotency →
o Growth (definition) →
o Development (definition) →
o Plant Life Cycles
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Annual →
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Biennial →
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Perennial →
Germ → Flower → Seed → Death
o Meristems →
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Pattern of growth depends on the locations of the meristems
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2 main types of meristems:
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Apical Meristems –
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o Location →
Fig. 35.12
pg. 729
o _______________________ growth (length) → gives rise to primary
plant body

Lateral Meristems –
o
o ____________________________ growth (thickens) →
o Found in ________________________ plants
o Growth Vocabulary → PRIMARY GROWTH!! (definitions)
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Root cap →
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Zone of cell division →
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Quiescent center →
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Primary meristems:
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Protoderm →
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Procambium →
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Ground →
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Zone of elongation →
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Zone of maturation →
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Miscellaneous vocabulary: stomata, guard cells, mesophyll (palisades/ spongy) →
KNOW THESE!!!!
o Growth Vocabulary → SECONDARY GROWTH!!
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2 lateral meristems:

Vascular Cambium → makes …
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
Cork Cambium → makes …
o Periderm →
o Bark →
o Plants have developmental plasticity:

Influenced by environmental factors

3 processes are important in the development of plants →

Morphogenesis →
o Depends on pattern formation →

This depends on positional information = signals of some kind
(chemicals) that indicate each cells location within an embryonic
structure; ex. polarity

Differentiation →
o Depends on control of __________________________________ →
regulating transcription and translation

Growth →
o Both contribute to plant form
o Plane of division (ex. asymmetrical) is an important determinant of form
o _________________________ accounts for 90% of expansion →
o Fig. 35.26 pg. 739
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Chapter 36 – Plant Transport
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Recall: transport proteins, selective channels, proton pumps, chemiosmosis, cotransport, aquaporins
KNOW THESE DEFINITIONS!!!
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Water Potential
o Depends on ________________________________ (hyper, hypo) AND
____________________________________
o Water moves from _________________ water potential to _____________ water potential
o Adding ____________________ = lowers water potential
o Adding ____________________ = increases water potential
Fig. 36.3 pg. 751
o Pure water = water potential = ____
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Plant Cell Compartments
o Symplast →
o Apoplast →
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Transport in Plants
o Bulk Flow → movement of water/ solutes by____________________________
o _________________________________ increase surface area to absorb water and nutrients

Mycorrhizae →
o Endodermis →
o Casparian Strip →
o Movement of xylem sap

Xylem sap consists of …

Moves by 2 forces:

1. __________________________ → (“push”)

Minerals accumulate in the stele = ________________________ water potential
therefore water flows IN from the ________________________, which yields a
positive pressure that force fluid UP the xylem
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
Guttation →
o (See Pic pg. 757)
o Occurs at night or when humidity is ______________


NOT the major mechanism
2. _________________________________________________ (“pull”)

Water lost from transpiration; therefore, water is drawn from other cells by
osmosis

Cohesion →

Adhesion →

This is the MAJOR mechanism of xylem sap!
Due to Hbonding of
water!
o So you could say that xylem transport is “_______________________”!!
o Control of Transpiration

Benefit of transpiration →

HOW stomata open and close → change shape!
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Shape change →

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Lots of K+ =

Little K+ =

Fig. 36.13 pg. 760

Stomata usually open at __________________ (decrease in transpiration)

CAM Plants →
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o Movement of Phloem

Translocation →

Usually “food” is the disaccharide ________________________
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Sugar “source” →

Sugar “sink” →

Always goes from source → sink


Requires ________________________ transport

Moves by bulk flow which is driven by pressure
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Chapter 38 – Plant Reproduction
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Alternation of Generations
o The plant life cycle goes through 2 “variations” or generations
o Gametophyte →


o Sporophyte

Produces _____________________________________ by ________________


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Usually the dominant generation of ___________________________
Flower Structure
o Non-reproductive parts: ________________________ and _______________________
o Reproductive:

Male →

Female →
o Complete Flower →
o Incomplete Flower →
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Development of Pollen (male gametophyte)
o In ________________________________ (pollen sacs) are diploid cells (called
______________________________________) that do meiosis to form haploid
__________________________________________, which give rise to _________________
(male gametophyte)
o Two cells: ________________________________ cell = produces sperm;
_____________ cell = produces pollen tube
o Pollen = ____ sperm
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Development of Embryo Sac (female gametophyte)
o Ovary → ____________________ → megasporocyte → goes thru _________________
forming 4 megaspores – only ___ survives
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o One end of the embryo sac has 1 egg and 2 _____________________ (which are used for …
.
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)
Pollination
o Definition →
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Prevention of self-fertilization
o Ensures egg/sperm from different parents (genetic variety!)
o Possibilities:



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Self-incompatibility →
Double fertilization
o Synchronizes ____________________________________ with _________________________
o 1 sperm + egg =
o 1 sperm + 2 polar nuclei =
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Ovary Development
o After double fertilization, ovule develops into a ___________________ and ovary develops into
___________________________
o Embryo development → divides into 2 parts:


o Enclosed in seed coat
o Mature seed = dehydrated (dormant!)

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When rehydrated, forms embryonic root (_______________________)
From seed to seedling
o Germination of seeds depends on imbibition →
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o _____________________________________ emerges first → water!
o Rest of process → Fig. 38.14 pg. 794
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Asexual Reproduction
o Asexual reproduction a.k.a. ______________________________ reproduction:
-

Results in clones

Can grow from one _______________________________ cell

Fragmentation →

Apomixis →

No genetic diversity

Cuttings →

Test-tube cloning; can cross genes
Plant Biotechnology
o Humans do selective breeding for our benefit
o Transgenic →
o Much debate → political, economic, ethical issues
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