Topic 8: Plant Diversity I

Question 1

What did land plants evolve from?

Answer 1

ancestral green algae

Question 2

What 2 groups are included in streptophytes?

Answer 2

Charophytes and land plants

Question 3

What kind of group is the streptophytes?

Answer 3

monophyletic

Question 4

What are the derived traits of streptophytes?

Answer 4

sporopollenin
rings of cellulose
structure of flagellated sperm
cell plate

Question 5

Define sporopollenin

Answer 5

layer of polymer, surrounds zygote, prevents desiccation

Question 6

What are the 7 derived traits of land plants?

Answer 6

alternation of generations
multicellular, dependent embryo
walled spores produced in sporangia
multicellular gametangia
apical meristems
cuticle
stomata

Question 7

What process turns a haploid gametophyte into a haploid gamete?

Answer 7

mitosis

Question 8

What process turns a diploid sporophyte into haploid spores?

Answer 8

meiosis

Question 9

Define sporangia

Answer 9

multicellular organs on sporophyte where spores are produced

Question 10

Define sporocytes

Answer 10

diploid cells in sporangia, undergo meiosis -> haploid spores

Question 11

Define spores

Answer 11

haploid reproductive cells

Question 12

Define gametangia

Answer 12

organs on gametophyte where gametes are produced

Question 13

What are the two types of gametangia? What do they each produce?

Answer 13

archengonia: produce eggs
antheridia: produce sperm

Question 14

What are apical meristems?

Answer 14

localized regions of cell division at tips of roots and shoots

Question 15

What is a cuticle?

Answer 15

waxy covering over all above ground parts

Question 16

What are the benefits and costs of the cuticle?

Answer 16

benefits:
- prevents desiccation
- provides some protection from microbes
cost:
- does not allow for gas exchange

Question 17

What is the stomata?

Answer 17

tiny openings on surface that can open and close and allow for gas exchange and water evaporation

Question 18

Define vascular tissue

Answer 18

tubes to transport water and nutrients

Question 19

What are the basal land plants?

Answer 19

nonvascular plants

Question 20

What are some characteristics of vascular plants? What kind of group is it?

Answer 20

seedless and seed plants
seedless vascular plants = ferns
paraphyletic

Question 21

What kind of plants are the majority of plant species?

Answer 21

seed plants

Question 22

Define seed

Answer 22

embryo with supply of nutrients within protective coat

Question 23

What is a characteristic of gymnosperms

Answer 23

“naked seed”

seeds not enclosed in a chamber

Question 24

What is a characteristic of angiosperms

Answer 24

“container seed”
flowering plants
seeds enclosed in a fruit
most dominant type of plant

Question 25

Define nonvascular

Answer 25

no specialized transport tissue

Question 26

Define peat

Answer 26

partially decayed organic matter

Question 27

What are the 6 derived traits of vascular plants

Answer 27

``` sporophyte dominant transport in vascular tissue roots leaves sporophylls spore variations ```

Question 28

Define lignin

Answer 28

polymer in cell walls of water

Question 29

Define xylem

Answer 29

tube that conducts water and minerals - contains lignin

Question 30

Define phloem

Answer 30

tube that conducts sugars, amino acids, organic products

Question 31

Define roots

Answer 31

organs that absorb water and nutrients from soil, anchor plants -> allow for taller growth

Question 32

Define leaves

Answer 32

main photosynthetic organs, increases surface area

Question 33

Define sporophylls

Answer 33

modified leaves with sporangia

Question 34

What are the two forms of spore variations

Answer 34

homosporous and heterosporous

Question 35

Define homosporous

Answer 35

1 type of sporangium produces 1 type of spore | sporangium ----meiosis--> spore ----mitosis--> bisexual gametophyte (produces egg and sperm)

Question 36

Define heterosporous

Answer 36

2 types of sporangia producing 2 spore types

Question 37

What are the two types of sporangia and what spore types do they produce?

Answer 37

megasporangium--meiosis-->megaspores--mitosis--> female gametophyte--mitosis--> egg microsporangium--meiosis-->microspores--mitosis--> male gametophyte --mitosis--> sperm

Question 38

What are ferns? (whats so special about them)

Answer 38

many are epiphytes

Question 39

What does epiphyte mean?

Answer 39

they use other plants as substrate, not parasitic -> grow on surface of trees

Question 40

What kind of spore production do ferns have?

Answer 40

honosporous

Question 41

Define sorti

Answer 41

clusters of sporangia under leaves