colonization of land

Question 1

Definition of plants

Answer 1

no strong definition yet, many disagreements

Question 2

4 major groups of land plants

Answer 2

1.mosses (belong to bryophytes)
2.ferns (seedless vascular plants)
3.gymnosperms (seeded vascualr-seeds onn leaves)
4. angiosperms (seeded vascular-seeds in fruits and flowering)

Question 3

non-vascular plants

Answer 3

-no vascualr tubes
-usually small and found in damp, moist areas

-get nutrients by slowly passing from cell to cell (diffusion)

-bryophytes eg)mosses, liverworts, and hornworts

Question 4

vascular plants

Answer 4

-have specialized tubes to transport water and food around plant.
-2 types:
1. xylem- water and nutrients from roots to rest of plant
2. phloem-food from leaves to rest of plant

-allows plants to be tall and found on land eg)ferns, trees

Question 5

which period did bryophytes arise

Answer 5

ordovician period ~475mya

Question 6

Which plants are embryophytes?

Answer 6

-land plants
-complex multicellular eukaryotes with reproductive organs
-mostly autotrophs but can be heterotrophs

Question 7

derived traits

Answer 7

traits that appeared by mutation which come from their most recent ancestor

Question 8

which adaptations allowed plants to move to land

Answer 8

1.adaptations for reproduction
2. preventing dehydration

Question 9

are algae photosynthetic. if so which algae

Answer 9

brown and green algae

Question 10

bryophyte contraints

Answer 10

1. moist enviornemts bc they have flagellated sperm
2. short bc they lack a vascular system, roots, and leaves

Question 11

key adaptations of bryophytes (5 derived traits of land plants)

Answer 11

1. embryophytes-retained their multicelluar embryo and protected
2. walled spores-to prevent spore from drying out
   3.gamete production in gametangia (protects gametes)
3. growth by apical meristems (tissues on ends of leaves stems etc.)
4. waxy cuticle and stomata (except liverworts. they have stomata like openings that cant open and close. and no cuticle so the plant takes up water over entire surface)

Question 12

phylum of bryophytes

Answer 12

liverworts, hornworts, and mosses

Question 13

stomata

Answer 13

pores that open and close by guard cells and exhchange gases. water is also let out by water vapour

Question 14

gametangia

Answer 14

an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants.

a gametangium is a haploid structure and formation of gametes does not involve meiosis.

Question 15

which period did seedless vascular plants rise

Answer 15

silurian period ~420mya

Question 16

which phylum are included in seedless vascular plants

Answer 16

horsetails, clubmosses, and ferns

Question 17

key adaptations of seedless vascular plants

Answer 17

vascular tissue-allows for reduced height constraint, structural support and efficent transport of water, nutrients and food

Question 18

4 plant phylum

Answer 18

Plantae are made up into four phylum: Angiospermorphyta (anthophyta), Coniferophyta, filicinophyta (pteridophyta), and Bryophyta, or flowering plant, conifer, fern, and moss, respectively.

Question 19

how are tall plants advantageous? what was the one consequence of growing taller?

Answer 19

they are able to capture more sunlight

more photosynthetic activity caused decrease in atmospheric CO2

Question 20

constraint of seedless vascular plants

Answer 20

still had flagellated sperm and need periodically moist enviornments for fertilization.

Question 21

where would seedless vascular plants be most abundant?

Answer 21

in moist enviornments where it may rain alot like BC

Question 22

gametophyte vs sporophyte

Answer 22

The sporophyte (2n) generation is represented by the asexual phase, while the gametophyte (n) generation is represented by the sexual phase.

Question 23

are charophytes haploid or diploid?

Answer 23

haploid since they only hsve gametophytes (flagellated sperm) therefore no sporophyte

Question 24

sporangium

Answer 24

A sporangium is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular.

Seed plants possess both male and female sporangia. A female sporangium produces a female spore, which develops into a female gametophyte (egg). same w males but develop into sperm

Question 25

what are the gametophytes in flowering plants

Answer 25

the pollen grain is the male gametophyte and the embryo sac is the female gametophyte

Question 26

ancestral traits vs derived traits

Answer 26

ancestral=traits that stayed in species from its ancestor. -reflects ancestors, evolutionary origin derived= traits that evolved bc of enviornment-innovative -reflects adaptations and are not found in ancestors

Question 27

example of mutualism relationship

Answer 27

pollinators and plants (angiosperms) benefits both of them

Question 28

whcih period did angiosperms rise

Answer 28

jurrassic ~142mya

Question 29

key adaptation 2 of gymnosperms (3 characteristics)

Answer 29

pollen -male gametophyte protected by spore coat -sperm in pollen -pollen travels by wind

Question 30

how are flowers advantageous

Answer 30

-requires less pollen production -higher reproductive succes (pollinators) -effective even at low population density

Question 31

coevolution of plants and pollinators (2)

Answer 31

-flowers exert pressures on bees: bees changed physilogically like more hair, body shape to effectively transport pollen -flowers favouring bilateral symmetry in colours like blue and yellow bees have exclusive access to nectar

Question 32

darwins theory of coevolution

Answer 32

orchid that had long spurs and nectary tip. darwin predicted a long tongue moth would be found that pollinates it

Question 33

2nd key adaptation or angiosperms

Answer 33

fruit: fleshy structure, ovaries helps to protect dormant seeds

Question 34

charophytes and land plants

Answer 34

more similarities between these two than chlorophytes and land plants like: 1. cell wall composition 2. cytokenesis 3. biochemistry 4. sperm ultrastructure charopphytes are closest relatives of land plants

Question 35

adaptation to grow on dry land

Answer 35

1. waxy cuticle (prevent water from evaporating out bc of waxy layer) 2. stomata (open and close to retain water) 3.vascular tissue (xylem able to suck water from roots-underground-to rest of plant

Question 36

adaptation to defy gravity

Answer 36

vascular tissue provided structural support (only in some animals). liginified vascular tissues (cell wall of xylem has lignin in it- a hydrophobic component that also provides structure)

Question 37

flavonoids

Answer 37

adaption to provide protection from uv rays for plants carbon structures in all but hornworts

Question 38

sporophyte and sporangium

Answer 38

sporangium is a structure of a sporophyte where apores are formed

Question 39

adaptions to reproducing on land (4 but idk if theres only four)

Answer 39

1. walled spores-to prevent dessication 2.gametes produced in multicellular gametangia (not in angiosperms)-protects reproductive cells 3.embryophtes (embryo develops in female gametophyte/maternal tissue-protects embryo) 4. alternation of generations (can switch between asexual and sexual and is advantageous as they can adapt to enviornmental consitions)

Question 40

advantage of sporophyte dominant life

Answer 40

Advantage of a dominant sporophyte was fertilization and dispersal of new/next generation timed with environmental conditions. therefore diploid spore responds better to environment eg)seeds will only germinate when conditions are right

Question 41

homosporous or heterosporous

Answer 41

homosporous= plant only produces one type of spore that gives rise to bisexual gametes eg) C-fern heterosporous= male or female spore that gives rise to either male or female gametes

Question 42

where do angiosperms produce gametes

Answer 42

theyre flowering plants so in the parts of flower; anther and ovule (other plants have gametangia that produce gametes)

Question 43

What is the difference between gametangia and gametophyte?

Answer 43

Gametangia is the sex organ that produces gametes in plants, 2. A Gametophyte is a haploid phase in the plant life cycle that produces gametes.