Week 13 L4: Plant Reproduction Flashcards
Where do flowers grow from?
floral meristems
meristems which form a determinacy
What is a meristem?
Pools of stem cells receive signals to promote development of specific tissues.
What is the meristem called when it produces vegetative meristem?
vegetative meristem VM
What meristems produce the reproductive structures?
inflorescence (IM) floral meristems (fm)
What happens to create flowering structures in arabidopsis?
The shoot apical meristem switches to a inflorescence meristem. one way switch
What does inflorescence mean?
WORD FR THE FLOWERING STALK OF A PLANT. Shoot meristem to an inflorescence meristem, the plant can make reproductive structures.
What gives rise to floral meristems?
inflorescence meristems
What promotes the identity transitions in the flower production?
Special TF promote identity transitions
in the floral meristem and within the shoot meristem it gets that inflorescence meristem.
What is reproductive phase change?
VM - IM - FM
vegetative meristem
What is the entire flowering structure celled?
inflorescence
What do floral meristems determine?
meristems which differentiate into floral organs, usually arranged in concentric whirls
What are the 4 whirls in arabidopsis?
1: sepals
2: petals
3: stamen
4: carpel
What are the sepals and petals often referred to as?
perianth
What are the perianth?
sepals and petals which are not involved in reproduction
STERILE
Important in repro strategies, specialised to attract a certain pollinator or promote the pollination in the wind etc
What is the structure that all plants share?
perianth
non-reproductive organs
What variations of reproductions organs can plants have?
bi-sexual plants with both male stamens and female carpel
or only 1
What are the male reproductive organs?
stamens
What is the female reproductive organ?
carpels
What non-reproductive organs does a lily have?
tepals
What is responsible for the variation in perianth in plants?
Their species
Why do floral structures matter?
understand the ecology and selection pressures of what goes on
Why do plants develop flowers?
Pollen dispersal
Less investment in pollen number
Pollinator interactions
Reproductive isolation
Flowers don’t need to make as much pollen as they attract pollinators unlike trees and grass.
What is the trees reproduction strategy?
coat the world in tree pollen as they cant attract pollinators
What does reproductive isolation mean?
flowering plants don’t need to be near a mate as the pollinators do the work for them (bridge the gap)
How do flowers benefit people?
food crops for human consumption, as grain derived from a floret
also are pretty - aesthetics
What are the 3 categories of plant?
Angiosperms
Gymnosperms
Ferns
What the flowering species?
ALL ANGIOSPERMS
eudicot
monocot
basal angiosperm
What category id Arabidopsis?
eudicot
What are some examples of gymnosperms?
CONIFERS
CYCADS
What is sporophyte?
diploid multicellular individual of a plant with alteration of generations that begins from diploid zygoyes and produces haploid spores
What does it mean to be sporophyte dominant?
diploid part of the life cycle is dominant
Are gymnosperms sporophyte dominant?
YES
What is the difference between gametophyte and sporophyte?
The multicellular diploid plant structure is called the sporophyte, which produces spores through meiotic (asexual) division. The multicellular haploid plant structure is called the gametophyte, which is formed from the spore and give rise to the haploid gametes.
What is the male and female gametophype?
F: EMBRYO SAC
M: POLLEN GRAINS
Do gymnosperms have a captive gametophyte?
YES, it gives rise to the gametes (cones)
What is a strobili?
cone of gymnosperms
In gymnosperms can the sexes be encased in one structure?
NO, they are in different structures
What are the megasporophyll and microsporophyll?
mega : leaf on which mega spores are formed Female
Micro : Male
What is the difference in ovules in strobili and flowers?
captive gametophyte - Naked ovule in strobili, exposed
flowers are completely enclosed (enclosed gametophyte) in the carpel - advantageous
What type of plant has male and females in separate cone?
strobili
How to gymnosperms pollinate?
the tough cone to protect organs means that the plants remain mostly wind or water pollinated
How do angiosperms pollinate?
phytophageous insects
What are phytophageous insects?
feed on green plants
What are the benefits of angiosperms pollination technique?
via insects
Use phytophagous insects to transfer pollen Reduce quantity of pollen produced Reduce number of female organs Increase distance of transfer Prevailing wind independent Opens up more ecological niches Enables co-evolution with pollinators
Why do flowering plants have a reduced number of female organs?
insects started visiting reproductive structures & the plants exploited this and used it for reproduction, and reduce number of female organs.
What are magaspores?
a spore in heterosporous plants giving rise to female gametophytes and usually larger than a microspore.
What do the megasporophyll close to form?
carpel which encloses the ovules
What is the megasporangium?
ovule
What is the anther also known as?
microsporangium
What is the microsporophyll?
stamen
