Plant biodiversity 2

Question 1

what is a sphenopsids breeding strategy?

Answer 1

homosporous

Question 2

what shape are sphenopsids sporangia?

Answer 2

cone shaped

Question 3

what is the embryogeny of sphenopsids?

Answer 3

exoscopic

Question 4

how many groups of ferns are there and which is most abundant?

Answer 4

6 and polypodiales are most abundant

Question 5

what are ferns breeding strategy?

Answer 5

most are homosporous except for a few heterosporous forms

Question 6

where are sporangia located on ferns?

Answer 6

on the underside of the leaf

Question 7

what is the embryogeny of ferns?

Answer 7

endoscopic

Question 8

what are Eusporangiate?

Answer 8

sporangia that arise from a group of epidermal cells

Question 9

what are leptosporangiate?

Answer 9

sporangia developed from a single epidermal cell

Question 10

describe the origin of leaves for microphylls

Answer 10

outgrowths which eventually become vascularised

Question 11

describe the origin of leaves for megaphylls

Answer 11

gaps between parts of outgrowths become filled in with leaf tissue as an advantage to get increase surface area for sunlight and to stop sunlight reaching plants below reducing competition

Question 12

where does sporangia form on ophioglossales

Answer 12

form on a fertile spike growing out the top of the plant

Question 13

Do psioltales have leaves?

Answer 13

no they have outgrowths called enations

Question 14

describe the sporangia and spores of marriatales

Answer 14

sporangia are fused into synangia and spores are monolete (single spore)

Question 15

how do osmundles release their spores?

Answer 15

cells full or air surrounding sporangia which burst releasing spores

Question 16

Describe the reproductive strategy of hydropteridales

Answer 16

they are heterosporous and roots have microspores which join with megaspores at surface of the water this joining causes a change in density and sporophyte sinks to the bottom and grows into a plant

Question 17

how do polypodiales sporangia develop?

Answer 17

the entire sporangia develop from one initial cell - the sporangia are very small

Question 18

what are 2 advantages of developing seed habit?

Answer 18

1) loss of need for free water - exploit more habitat

2) parental control over when the seeds are released depending on the correct conditions

Question 19

when did gymnosperms dominate?

Answer 19

throughout the mesozoic

Question 20

what are the 4 phyla of extinct gymnosperms?

Answer 20

1) pteridosperms
2) cordaites
3) glossopterids
4) Voltziales

Question 21

what are the 4 phyla of extant gymnosperms?

Answer 21

1) ginkgos
2) cycads
3) conifers
4) Gnetales

Question 22

what are 3 features of ginkgos?

Answer 22

1) male or female reproductive structures occur on different plants in the axils of scale leaves
2) ovules are borne in pairs
3) sperms have flagellum to swim down to ovule

Question 23

what are 3 features of cycads?

Answer 23

1) seeds are poisonous
2) males and females are separate plants
4) females produce cones which either grow out the top of the plants either terminal or lateral

Question 24

describe the reproductive strategy of conifers

Answer 24

reproductive organs in cones, male gametes are delivered by a pollen tube into cone which closes once fertilised protecting the seed over winter and then releases once the weather is right

Question 25

how are seeds of conifers dispersed?

Answer 25

wings help them to be dispersed by air but some are grown in fruits for dispersal by animals

Question 26

how many species of Gnetales are there?

Answer 26

160

Question 27

3 facts about Gnetales

Answer 27

1) pollinated by beetles
2) closely related to conifers
3) have flower like structures

Question 28

what is mosaic evolution and where is it common?

Answer 28

during times of environmental stress plants can adapt by a single organ evolving, say leaves, while essentially maintaining their genetic makeup, its very common in plants

Question 29

3 important features of land plants

Answer 29

1) asexual reproduction is common in the plants kingdom
2) polyploidy is common
3) plants can readily hybridise

Question 30

are population size dynamics a problem in the plant kingdom?

Answer 30

no very small populations can persist

Question 31

what are the 4 living fossils?

Answer 31

1) gymnosperms
2) bryophytes
3) sphenopsids and ferns
4) lycopsids

Question 32

what did algae give rise to?

Answer 32

liverworts, hornworts, tracheophytes and mosses

Question 33

is the tempo and mode of evolution different for plants and animals?

Answer 33

yes plants recover post trauma much better the animal kingdom is mainly shaped by mass extinctions

Question 34

what drives plant evolution?

Answer 34

major plant groups often persist rather than face extinction sometimes they have a new lease of life e.g. bryophytes as epiphytes

Question 35

what are the 4 main things that drive plant evolution?

Answer 35

1) environmental change
2) climate change
3) atmospheric composition
4) land surface area

Question 36

what happened to plants in the middle silurian?

Answer 36

switch from gametophyte dominant to homosporous sporophyte dominant

Question 37

what happened to plants in the early devonian?

Answer 37

plants became lignified and heterosporous plants evolve = 1st seed plants

Question 38

what happened to plants in the late carboniferous?

Answer 38

increase in plants cause decrease co2 and shift to ice age world - plants store carbon in swamps and coal and CO2 put into oceans in limestone

Question 39

what happened to plants in the late permian?

Answer 39

wilson cycle caused a madd extinction and volcanic eruptions caused super heating

Question 40

what happened to plants in the early triassic?

Answer 40

world became dominated by gymnosperms

Question 41

what happened in the late jurassic?

Answer 41

continents fall apart and there is a mass extinction

Question 42

what happened to plants in the late cretaceous?

Answer 42

angiosperms dominate over gymnosperms