plants

What does CHS form in petunia

multigene family of 12 genes

Why does sectoring occur in non-transgenic petunia

4 homologous CHS gene fragments interfere w/ each others expression

What can transcriptional gene silencing mutations be complemented by

Transformation in wild type sequence

What can gene expression be suppressed by

Stopping mRNA or protein synthesis

what are levels of gene expression controlled by

transcription factors and chromatin

What causes genes to be abnormally inactivated in mutation-related transcriptional gene silencing

Deletion, molecular damage to coding sequence of promoter

densities of earth + mars

earth = 1.2 kg m -3, mars = 0.015

how do gonidium differentiate

symmetrical cytokinesis to 32 cell embryo, asymmetrical cytokinesis to small and large cells, small form soma, large form immature gonidium

what are the 2 groups of viridiplantae

chlorophyta, streptophyta

what is luminescence

light emitted due to chemical reaction

what are homospores

spores identical in size + morphology but form male + female gametophytes

what do gibberellins do

promote germination by stimulating synthesis of amylase, promote radicle + embryonic shoot growth

what happens when energy is absorbed by pterin

passed to FAD which is reduced to FADH, autophosphorylation of crytochrome + translocation to nucleus

what are sporangium

tissues where haploid spores form

what is a sporophyte

diploid plant that produces haploid spores by meiosis

where are seeds found in gymnosperms

cones

what is the hornwort gametophyte like

thick + thallose

what is a volvox

model colonial chlorophyte, differentiates into somatic + reproductive cells, sexual + asexual

what is the antheridium

male part of gametophyte

what is a gametophyte

haploid plant that produces haploid gametes by mitosis

what is the gametangium

sexual tissue where gametes form

pterin absorbance

380nm

FAD absorbance

450nm

what is the gonidium

asexual reproductive cell or group where reproductive cells are produced

what are seeds like during formation

partially dehydrated, protected by tough seed coat

what do amylases in the seed do

degrade endosperm to glucose

what features evolved in embryophyta

embryo, cuticle, multicellular sporophyte, sporangia, gametangia

where are lycopodium sporangia produced

on strobuli

what is the % oxygen on mars

0.17

what plants are in the pteridophyte group

club mosses, ferns, horsetails

features of cooksonia

no leaves or roots, apical sporangia, dichotomous branching, tracheids

what did moss leaves develop from

filamentous protonemata

what is the androecium

diploid male reproductive structure

what do unicellular chlorophytes do when under environmental stress

differentiate to become motile or find alternative mating type

how does the protoderm form

asymmetric cytokinesis from octant to dermatogen

2 ways cell fates between interior of embryo + protoderm can be determined

inherent cytoplasmic asymmetry, cuticle specifies protoderm

how does inherent cytoplasmic asymmetry diverge cell fates between interior of embryo + protoderm

emb30 and fass are developmental mutants, emb30 undergoes random cytokinesis, fass undergoes symmetrical cytokinesis

where is the ATML1 gene expressed

protoderm, apical cell of 2-cell stage

how does the cuticle specify the protoderm

acts as a marker for the epidermis, protoderm inherits some of original zygotic cell wall, cytokinesis induces non-protoderm cell fate

what is ts11

temperature inducible mutation that causes somatic embryos to be arrested at protoderm stage

where is EP3 purified from

cell walls

roles of plant growth regulators

regulate development, coordinate gene expression, developmental patterning, growth

in crassulean acid metabolism, what is CO2 catalysed to

oxaloacetic acid

what is kranz anatomy

chloroplasts containing bundle sheath cells surrounding vascular bundles and connected to mesophyll cells by plasmodesmata in C4 plants

in C4 p/sis, where is C3 acid transported to and what is regenerated

mesophyll, phosphoenolpyruvate

what does crassulean acid metabolism require

temporal control of metabolic pathways and cell function

where are C4 compounds transported and what happens

bundle sheath cells, decarboxylated and free CO2 fixed in C3 p/sis

2 types of mutations in floral patterning

constitutive, conditional

what do class E genes control

floral meristem

what is the endosperm

triploid tissue that nourishes developing embryo

what do class B and C genes interact to form

stamen

where do dicot roots develop from

radicle

what do class A and B genes interact to form

petals

molecular reprogramming during which processes can cause changes to DNA structure

meiosis, gametogenesis, zygogenesis

how many CHS genes are there in petunia

8 complete genes, 2 5' fragments, 2 3' fragments

epigenetics definition

heritable changes in gene expression without changes in DNA sequence

what happened when a silenced plant tissue was inoculated with a virus

gfp mRNA made

what was the mobile signal in the northern blot gene silencing experiment

small mobile RNA

in an experiment, what happened when the plant was infected with TMV

gene silencing

how does epigenetic affect DNA

changes physical structure but not sequence

if gfp mRNA is present in PVX virus, what is gene silencing due to

transcriptional gene silencing

if gfp mRNA is absent in PVX virus, what is gene silencing due to

post transcriptional gene silencing

how do you carry out a northern blot

nylon filter on gel, weight on gel, DNA on nylon, treat with UV light which breaks open DNA and cross links it to nylon polymer, negative charge on nylon

microgametogenesis process

in the microspore the haploid nucleus divides by mitosis to form microgametophyte which contains large vegetative nucleus and smaller generative nucleus, generative nucleus divides by mitosis to form 2 haploid sperm nuclei

what happens in the homomorphic gametophytic self incompatibility system

pollen tube arrested in style transmission tissue if S allele is identical to S allele in carpel

what happens in the homomorphic sporophytic self incompatibility system

pollen fails to germinate on stigma if microgametophytic S allele is identical to S allele in carpel

what happens in heteromorphic sporophytic self incompatibility

pollen fails to germinate of stigma if microgametophytic S allele is identical to S allele in carpal and S allele is linked to different floral morphologies

what does the exine derive from

microsporangium

what does the intine derive from

gametangium

what is intraspecific incompatibility

pollen germinates but can't fertilise egg if its from the same plant

what do self incompatibility systems depend on

multiallelic S locus

ovule development process

4 spores form by meiosis in megasporangium, 3 degenerate and 1 divides 3 times by mitosis to form 8 nuclei

how can extrinsic positional info determine embryo and suspensor cell fates

zygote attached to maternal tissue so has intrinsic polarity, tissues gives positional info to zygote and causes cytoplasmic gradient, asymmetric cytokinesis of cytoplasm

what does the sus gene do in the suspensor

suppress embryonic development

what is embryogenesis in animals

zygote forms embryo with different cell fates

what does asymmetric cytokinesis determine

cell differentiation and morphogenesis

what defines different tissues and organs of a plant

differential gene activities

what is the 1st cell division of the zygote like

forms small apical cell which forms embryo, forms large basal cell which forms the suspensor

3 ways different fates of the suspensor and embryo can be established

cell size, extrinsic positional info, regionalised zygotic cytoplasm

how does cell size determine embryo or suspensor cell fate

determines fate between soma and gametangia

where is SHR usually expressed

E/C initial, nucleus of endodermis, stele

CLAVATA role

cell proliferation

what is STM needed for

cell proliferation

what is the arabidopsis homologue of knotted 1

STM

where is knotted 1 usually expressed

central zone of shoot apical meristem

what do KN1 and STM control

class 1 homeobox genes

the inductive niche model only works if …

promtors are tightly regulates, RNA and protein are rapidly synthesised and degraded

what is SCR expression required for

asymmetric cell division of E/C initial

how is the inductive niche model of shoot apical meristem maintained

WUSCHEL and CLAVATA mutually inhibit each others expression in negative feedback loop that maintains SAM size

what is wuschel needed for

stem cell identity

what is SHR

TF that induces expression of SCR

what structures make up the root apical meristem

quiescent centre, lateral root cap, columella

shoot apical meristem role

site of continuous organ formation

where is SCR usually expressed

E?C initial, endodermis cytoplasm

how can root apical meristem identity be controlled

UV laser kills cell in quiescent centre, older adjacent cell dedifferentiates to replace it, mature cells control state of QC cells by instructive signals

how are meristems embryonic

root and shoot apical meristems defined in embryo and continue to express genes expressed in embryo

where does primary growth arise from

apical meristems

what does primary growth form

shoots and roots

what does secondary growth arise from

intercalary and lateral meristems that cause buds and increased plant thickness

how do plant organs develop

from meristems, determinate growth, according to pattern of differentiation and organogenesis