Plant diversity pt. 2

Question 1

what adaptations did seed plants get further than bryophytes and seedless vascular plants have?

Answer 1

• seeds
• reduced gametophytes
• heterospory
• ovules (protect female gametophytes) and pollen (protect male gametophytes)

Question 2

how does reduced (tiny) gametophytes developing directly in the sporangium help seed plants

Answer 2

Protection from elements such as UV radiation, desiccation.

Question 3

what’s different about the relationship between gametophyte and sporophyte in seed plants

Answer 3

gametophytes are nutritonally dependent on the sporophyte (opposite of what is was for bryophytes)

in seedless vascular plants gametophytes are reduced but independent of sporophytes.

Question 4

most seed plants are heterosporous or homosporous

Answer 4

heterosporous

Question 5

whats dioecious and monoecious

Answer 5

dioecious-separate male and female plants
monoecious- male and female on same plant

Question 6

what process produces megaspores/microspores from megasporocytes/microsporocytes

Answer 6

meiosis> 2n to n

4 megaspores/microspores are produced but only 1 survives

Question 7

what process makes gametophytes from megaspores/microspores

Answer 7

mitosis> n to n ploidy dont change

Question 8

what’s an integument

Answer 8

2n sporophytic tissue that envelopes and protects the megasporangium

Question 9

how many integuments do gymnosperms and angiosperms have

Answer 9

gymnosperms have 1 integument, angiosperms have 2 integuments

Question 10

what’s contained in the ovule? what develops in the ovule?

Answer 10

megasporangium (2n), megaspore (n), and integuments (2n). the female gametophyte will develop in the ovule.

Question 11

what does pollen grain (n) develop from and contain?

Answer 11

develops from a microspore (n) and contains the male gametophyte (n), enclosed in a pollen wall (2n) which contains sporopollenin. The pollen wall is secreted by microsporocytes (2n).

Question 12

how can shape of pollen grains and wall spikes be used

Answer 12

to identify the plant species it came from

Question 13

what’s pollination

Answer 13

transfer of pollen to the ovule through a pollen tube in the mircropyle of the ovule.

Question 14

what’s the advantage of pollen grains

Answer 14

they can travel large distances without needing to swim in water

Question 15

if sperm fertilizes an egg in a seed plant zygote will grow into a…

Answer 15

sporophyte

Question 16

what’s an advtantage of seed as opposed to nonvascular plants spores

Answer 16

the ovule develops into a multicellular seed, which can remain dormant for longer periods of time than spores of nonvascular plants. There is an embryo with a food supply, and protected seed coat (developed from integument).

Question 17

what characteristic do seed plants share with archaeopteris (the first tree)

Answer 17

heterospory, although archaeopteris did not make seeds

Question 18

what 4 phyla are within the gymnosperms group? what characterizes each

Answer 18

1. cycads - palm like leaves, large cones
2. gnetophytes -gnetum, ephedra, welwitchia
3. ginkgos -ginkgo bibola, ‘maiden hair’ tree
4. conifers -pines, spruce, fir, junipers, larch, sequoia

Question 19

earliest gymnosperms lived in _ but survived better in _ due to seeds pollen thick cuticles and small SA of their needle leaves.

Answer 19

• lived in moise carboniferous ecosystems.
• survived better in drier climates.

Question 20

common charactersitics of all gymnosperms

Answer 20

• dominance of sporophyte
• seed as resistant, dispersible stage of life cycle
• pollen as airborne agent bringing sperm to female
• all heterosporous
• most produce cones
• wind is primary dispersal

Question 21

scales of cones are

Answer 21

specialised sporophylls (modified leaves to produce spores)

Question 22

what are male cones called? female cones?

Answer 22

pollen cones, ovulate cones

Question 23

what are the steps of the pine life cycle (gymnosperms)

ploidy, what u start w/ whats produced?

Answer 23

1. each tree has both ovulate and pollen cones (monoecious). Microsporocytes divide by meiosis (each divide =4 microspores (n))
2. The microspore develops into a pollen grain (male gametophyte (n) and surrounding wall (2n).
3. pollination occurs when the pollen grain reaches the ovule, germinating to form a pollen tube that grows through the megasporangium.
4. while the pollen tube develops. the megasporocyte undergoes meiosis > 4 haploid megaspores, only 1 survives.
5. the megaspore becomes female gametophyte (containing 2-3 archegonia which each form an egg)
6. once eggs are mature, sperm cells are fully developed and travel down the pollen tube for fertilization.
7. zygote develops into embryo (2n) and ovule becomes a seed.

Question 24

an ovulate cone scale has _ ovules each containing a megasporangium

Answer 24

2

Question 25

how long after pollination does fertilization usually occur?

Answer 25

1 year after pollination.

Question 26

all eggs may be fertilized in pines but only _ zygote develops into an embryo (2n).

Answer 26

only 1 zygote

Question 27

cycadophyta characteristics

Answer 27

* large cones * palm-like leaves * flagellated sperm (suggests descent from seedless vascular, they might be first gymnosperms).

Question 28

which gymnosperm phyla is most endangered

Answer 28

cycadophyta > 75% species are endangered by habitat destruction.

Question 29

characteristics of ginkgophyta

Answer 29

* flagellated sperm (descent from seedless vascular) * deciduous (drop their leaves), fan like leaves that turn gold in fall * tolerant to pollution * people only plant males because female seeds stink when they decay

Question 30

characteristics of gnetophyta

Answer 30

* tropical and desert habitats * welwitschia mirabilis can live 1000s of years (aren't a lot around tho) * ephedra=desert shrubs * gnetum=tropical trees, vines, shrubs in africa and asia

Question 31

which is largest and most diverse gymnosperm phylum

Answer 31

pinophyta (or coniferophyta)

Question 32

pinophya/coniferophyta characteristics

Answer 32

* most species have woody cones (junipers have fleshy cones -berries) * most are evergreen * some species are deciduous -drop needles * leaves are needle-like

Question 33

how are conifers important economically

Answer 33

for lumber, and chemical compounds

Question 34

what are angiosperms

Answer 34

flowering plants

Question 35

what are angiosperm dispersal factors ## Footnote and examples

Answer 35

* wind - common in grasses. * animals -fruit eating animals like hummingbirds. * insects- bees, moths, flies

Question 36

floral organs (flowers) are specialised_?

Answer 36

sporophylls

Question 37

what are the 4 whorls of a flower list and describe

Answer 37

1. sepals -outermost, usually green 2. petals -showy, inner whorl, attracts pollinators 3. stamens-microsporophylls that produce microspores which develop into pollen grains 4. carpels (aka pistil)-megasporophylls that produce megaspores that develop into female gametophytes.

Question 38

# stamens and carpels which ones female which is male?

Answer 38

stamens-male carpels-female

Question 39

what are stamens composed of

Answer 39

anthers and filaments

Question 40

what are carpels composed of

Answer 40

the stigma, style and ovary.

Question 41

flowers can vary in _, _ and _

Answer 41

symmetry, floral parts, and how often they flower

Question 42

what's the difference between annual, biennial and perennial flowering

Answer 42

annual-only flower once biennial-every two years perennial -every year

Question 43

what are the fruits of angiosperms really

Answer 43

ovary wall that has thickened around the seeds

Question 44

how are fruits an advantage

Answer 44

protects the seeds and aids in dispersal

Question 45

what adaptations do fruits have for dispersal

Answer 45

* propellers (maple seeds) * parachutes (dandeltions) * rough coats to stick to animals (burs) * sweet tasting (so animals want to eat it and poop out in diff location)

Question 46

Describe the steps of the angiosperm lifecycle | ploidy, what u start with, what's produced

Answer 46

1. in the megasporangium (female) the megasporocyte (2n) divides by meiosis producing 4 megaspores (n), but only one survives. 2. megaspore (n) undergoes mitosis producing the female gametophyte (n). 3. in the microsporangium on the anther (male), each microsporangium contains microsporocytes (2n) that divide by meiosis, producing microspores (n). 4. a microspore develops into a pollen grain. the generative cell of the male gametophyte will divide forming 2 sperm. the tube cell will produce the pollen tube. 5. after pollination, eventually two sperm cells are discharged in each ovule. 6. the seed germinates into a new sporophyte (2n). 7. zygote develops into a embryo that is packaged into the seed with the food supply. 8. double fertilization occurs.

Question 47

what's contained within the carpel

Answer 47

the ovary and within that the ovule.

Question 48

is pollenation in angiosperms direct or indirect

Answer 48

indirect. pollen grains land on stigma, not directly on ovule. needs pollen tube to get sperm inside.

Question 49

what's double fertilization in angiosperms

Answer 49

Two sperm were discharged in each ovule. one sperm fertilizes the egg, forming the zygote. the other fertilizes the central cell, forming a 3n endosperm (food supply)

Question 50

what is the 3n endosperm in angiosperm double fertilization made up of

Answer 50

2 polar nuclei and 1 sperm.

Question 51

in pollination in gymnosperms indirect or direct?

Answer 51

direct, pollen grain directly to ovule

Question 52

what's the structure of the male gametophyte in angiosperms? | describe the components

Answer 52

* prothallial cells -produce the generative and tube cells * generative cell- produces sperm * tube cell- produces the pollen tube * exine -outer wall composed of sporopollenin

Question 53

what's the structure of the female gametophyte (aka embryo sac) in angiosperms? | describe the components

Answer 53

* antipodal cells -cells at the far end of the gametophyte * polar nuclei -forms the endosperm following double fertilization * synergids -near the egg, aid in fertilization * egg -female gamete

Question 54

what period did angiosperms orginate

Answer 54

cretaceous period

Question 55

evolution of angiosperms was often a result of

Answer 55

plant-animal interactions. anti-herbivory compounds, mutualistic co-evolution of animal pollinators (both plant and animal evolved to be compatible for pollination). flower shape and colour may be very specific to pollinator preference.

Question 56

what are the basal angiosperms ## Footnote what characteristic did they have

Answer 56

water lillies, star anise and amborella ## Footnote they had spiral arrangement of floral parts

Question 57

describe the magnolids

Answer 57

* within angiosperms. * include magnolias, laurels, black pepper plants. * woody and herbaceous * spiral arrangement of floral parts

Question 58

describe monocots | examples and characteristics

Answer 58

* include orchids, grasses, palms * one cotyledon (mono=one) * fibrous root system * simple leaves with parallel veins * vascular tissue scattered * pollen grain has 1 opening * floral organs usually multiples of 3

Question 59

describe eudicots | examples and characteristics

Answer 59

* legumes, roses, flowering trees * 2 cotyledons (think di=2) * tap root system * leaf venation is netted * vascular tissue arranged in ring (*when you say eu you make ring w mouth) * pollen grain has 3 openings * floral organs usually in multiples of four or five ## Footnote (eudicots have more of every thing than monocots) think di=2 bigger than mono=1.