L4:Plant Reproduction

Question 1

how do plants overcome that fact that they cannot search for a partner

Answer 1

• use a vector for pollen dispersal

- become self fertilized

Question 2

what are the two types of asexual reproduction

Answer 2

vegetative

agamospermy

Question 3

true or false, ~80% of angiosperms reproduce asexually

Answer 3

true

Question 4

true or false, trees add modules vertically to grow

Answer 4

true

Question 5

what is a phalanx

Answer 5

invade as a group

Question 6

what is a geurrellia type

Answer 6

invade using individual parts

Question 7

where is vegetative reprod. best developed

Answer 7

environments where sexual reprod. is disadvantaged
lack of pollinators
unfavorable conditions for flowering

Question 8

what is the trade off in vegeative reproduction

Answer 8

• trade offs between maintaining successful genotype and costs of producing clones with little genetic diversity for long term evolutionary change

Question 9

what is agamospermy

Answer 9

asexual reprod. via seeds, but the seeds are a clone of the parental type

• seeds are produced without fertilization
• sometimes requires stimulus of pollination to occur
• common in 75% apomicts: Asteraceae, Poaceae, Rosaceae

Question 10

what is the advantage of agamospermy

Answer 10

• seed dispersal and dormancy adaptations and preserve successful genotypes but unable to provide genetic novelty
• true obligate agamospermy rare
  eg. blackberry, dandelion

Question 11

disadvantage of selfing

Answer 11

reduce genetic diversity

Question 12

advantages of selfing

Answer 12

• provide reproductive assurance
• reduce mating costs
• preservation of successful genotypes (in unstable env.)

Question 13

what is self pollination

Answer 13

• perfect flowers (most angiosperms)

Question 14

what is autogamy

Answer 14

takes place within the flower

Question 15

what is geitonogamy

Answer 15

between flowers of the same plant

Question 16

what does the level of autogamy depend on

Answer 16

degree of separation between anthers and stigma

Question 17

what does level of geitonogamous crosses depend on

Answer 17

depends on pollinator behaviour

Question 18

examples of autonamous selfing

Answer 18

cardmine

Question 19

what is cleistogamous

Answer 19

self fertilize before they open eg. Ahipara

Question 20

how does Myosotis delay selfing

Answer 20

lifts anthers above corolla

Question 21

how does M. spathulata self fetilize

Answer 21

anthers dehisce shortly after opening depositing pollen directly on the stigma causing flower to self fertilize

Question 22

what are mechanisms of self incompatibilty

Answer 22

• pollen grains may not grow of self incompatible stigmas or may grow slowly
• chemical barrier on stigma can be broken down by foreign pollen
• gametic incompatibility, gametes fuse but dont form viable offspring

Question 23

what is monoecy

Answer 23

the two sexes are found on all individuals , but in separate flowers

Question 24

what is dioecy

Answer 24

male and female flowers on separate genets

Question 25

what is gynomonoecy

Answer 25

the same individual bears both perfect and female flowers

Question 26

what is andromonoecy

Answer 26

the same individual bears both perfect and male flowers

Question 27

What is Androdioecy

Answer 27

male and hermaphrodite flowers on separate genets

Question 28

what is gynodioecy

Answer 28

female and hermaphrodite flowers are on separate genets

Question 29

true or false, monoecious plants are often temporally and spatially separated

Answer 29

true

Question 30

how do flowers attract pollinators

Answer 30

- chemical signals for pollinators - UV - nectar, pollen - scent, nigh or day, thermogenesis - sexual deception eg. orchids

Question 31

how does H. muscivorus attract pollinators

Answer 31

- foetid scent in the morning - resembling flesh and dung - flies enter floral chamber but are trapped until the next morning when they are showered with pollen before they leave

Question 32

what is pseudocopulation

Answer 32

- immitating female sex hormones and female, in wasps, orchid

Question 33

what are the 3 pollinating systems

Answer 33

open, direct, closed

Question 34

open pollination

Answer 34

accessed by most pollinators

Question 35

what are direct access flowers

Answer 35

has a limited range of pollinators

Question 36

what is closed access flowers

Answer 36

has one specific pollinator