L14 Plants pt 1

Question 1

what are the characteristics of most plants

Answer 1

multicellular, eukaryotic, photoautotrophic

Question 2

what kingdom are plants classified in

Answer 2

kingdom plantae

Question 3

what is the most diverse group of plants? describe them

Answer 3

angiosperms; flowering plant

Question 4

what are the benefits of plants?

Answer 4

provide O2 and CO2; are a food source for many animals

Question 5

what are the 4 main unique characteristics of plants? describe each briefly

Answer 5

• alternation of generations (gametophyte and sporophyte)
• vascular tissue development (xylem and phleom)
• evolution of seeds/pollen (multicellular, dependent embryos)
• evolution of flowers (sporophyte with protected gametes and seeds)

Question 6

name some additional derived traits of plants, and what they are useful for

Answer 6

• apical growth
• waxy cuticles
• chemical defense compounds
• symbiotic associations with fungi and plants

Question 7

plants alternate between multicellular stages, what are these?

Answer 7

• multicellular gametophyte generation
• multicellular sporophyte generation

Question 8

explain the steps of the alternation of generations process (e.g. for a green algal lifecycle)

Answer 8

• begins with mitosis of multicellular alga (n)
• gametes fertilize (n)
• zygotes (2n) complete meiosis to make haploid cells (n) (begin cycle again)

Question 9

explain gametophyte and sporophyte multicellular stages

Answer 9

• gametophyte (haploid) makes haploid gametes through mitosis
• gametes fuse to make diploid sporophyte, which makes haploid spores through meiosis followed by mitosis

Question 10

what is the dominant stage in fern life cycles, gametophyte or sporophyte

Answer 10

sporophyte

Question 11

explain one evolutionary trend through the multicellular stages

Answer 11

size change

• reduction in gametophyte size
• increase in sporophyte size

Question 12

what is one way to (informally) group land plants. what is the importance of this?

Answer 12

through the presence and absence of vascular tissue (xylem, water and phloem, sugars)

• vascular plants have a competitive advantage b/c they can grow taller and stay hydrated longer, and are less water dependent

Question 13

explain the evolution of pollen

Answer 13

• aka male gametophytes
• fertilization doesn’t need release of sperm
• water isn’t needed for sexual reproduction
• gametophytes stay within the larger sporophyte
• meiosis makes haploid microspores
• mitosis makes haploid pollen grains

Question 14

explain the evolution of seeds

Answer 14

• aka embryos of gymnosperms/angiosperms
• egg fertilized by sperm in ovary
• have food for embryo development
• protected from dehydration
• when dispersed by wind or animals, can adapt
• mature seeds are found in many structures (simple seeds, fleshy fruits, dry nuts)

Question 15

what do the flowers in angiosperms contain

Answer 15

organs for sexual reproduction

Question 16

every pollen has ____ sperm

Answer 16

2 (one gives rise to embryo, one gives rise to endosperm)

Question 17

Haploid male gametes (sperm) in pollen grains arise from __________ in _________

Answer 17

microspores; anthers

Question 18

A haploid female gamete (egg) forms within an _______ (or ____________) located within the ______

Answer 18

ovule; megasporangium; ovary

Question 19

Fertilization of eggs by sperm (pollen) results in seeds containing the ________ sporophyte embryo and a ________ food source called the ____________

Answer 19

diploid; triploid; endosperm

Question 20

benefits of apical meristems

Answer 20

• cells differentiate into various tissues
• helps with access to water, nutrients (roots), and light (shoots)

Question 21

what are plants

Answer 21

eukaryotic, multicellular, photoautotrophic organisms

Question 22

how did plants evolve

Answer 22

branched from protists forming branch shared with fungi and animals

Question 23

what phylogenetic relationships account for plant diversity

Answer 23

angiosperm flowering plants, gymnosperms (conifers), ferns, mosses, horsetails