land plants

Question 1

what are the general characteristics of land plants?

Answer 1

-most live on land
-eukaryotes
-multicellular
-photosynthetic (photoautotrophs)
-cell walls are made of cellulose
-alternation of generations

Question 2

what are the four main groups of land plants?

Answer 2

1. non-vascular plants (moss)
2. seedless vascular plants (ferns)
3. gymnosperms (pines)
4. angiosperms (flowering plants)

Question 3

what are the benefits to moving life on to land?

Answer 3

spacious
unfiltered sunlight
higher levels of atmospheric CO2
rich source of mineral nutrients
relatively few herbivores and pathogens

Question 4

what were the challenges to moving life on to land?

Answer 4

less water
need to resist gravity

Question 5

how were early ancestors able to overcome the challenges of moving on to land

Answer 5

adaptations !! :)

Question 6

what are three traits that are shared by charophytes and land plants?

Answer 6

1. rings of protein in the plasma membrane
2. sperm structure resembles charophyte sperm structure
3. special type of cytoskeleton called a phragmoplast during cell division

Question 7

is the shared common ancestor between charophytes and land plants and synapomorphy or a symplesiomorphy?

Answer 7

symplesiomorphy

Question 8

one way to adapt to life on land was through sporopollenin. what is it?

Answer 8

a tough polymer that can be used in charophytes to protect the zygote or plants to protect the walls of plant spores

Question 9

sporopollenin’s use in charophytes and plants are stages for?

Answer 9

dispersal

Question 10

what are some synapomorphies of land plants that are not in charophytes? (4)

Answer 10

1. they have adaptations for water conservation
2. they have multicellular, dependent embryos
3. resources were compartmentalized into roots and shoots
4. alternation of generation

Question 11

how do plants conserve water?

Answer 11

through their waxy cuticle (on the epidermis) and stomata (pores in the epidermis)

Question 12

how does the dependent embryo in plants work? what happens to the zygote?

Answer 12

the zygote is kept safe in a protective layer and the embryo has specialized placental cells that transfer nutrients

Question 13

what do roots and shoot do?

Answer 13

roots search for water and minerals below ground and shoots search for light and gasses above ground

Question 14

what is an apical meristem?

Answer 14

specialized structures on the tips of the ends of roots and shoots that allow them to differentiate

Question 15

what is alternation of generation? what are its two forms?

Answer 15

a different form that can coexist at the same time; multicellular haploid (n) and multicellular diploid (2n) forms

Question 16

how do you know whether the haploid or diploid form is dominant?

Answer 16

the dominant form looks like a plant and is responsible for photosynthesis

Question 17

in ferns, gymnosperms and angiosperms, is the haploid or diploid form dominant?

Answer 17

diploid (2n)

Question 18

in the current diversity of plantae, what form is most successful?

Answer 18

angiosperms (flowering plants)

Question 19

bryophytes (nonvascular plants) are not a monophyletic group. true or false?

Answer 19

true

Question 20

what makes a plant, like bryophytes, nonvascular?

Answer 20

they do not have a xylem or a phloem, and they cannot resist gravity

Question 21

what are some characteristics of bryophytes?

Answer 21

-thin tissues
-thin, waxy cuticle
-stomata is fixed in position; cannot be closed
-some lack true vascular tissues like leaves, stems and roots

Question 22

how do bryophytes reproduce?

Answer 22

plants need to live in water, and release flagellated sperm directly into the environment

Question 23

in bryophytes, are haploid or diploid gametophytes dominant?

Answer 23

haloid (n)