3.1 Exploring Plant Diversity

Question 1

importance of plants

Answer 1

-Form the base of almost all food chains
-Provide food, fuel and fibre
-Found within medicines (e.g. Aspirin)
-Release O2
-Cycle nutrients
-Clean air, purify water, absorb carbon and detoxify soil
-Some can clean up pollution that seeps into the environment

Question 2

what are 3 characteristics that all plants share?

Answer 2

-eukaryotic
-cell walls contain cellulose
-carry out photosynthesis

Question 3

evolution of plants

Answer 3

Transformed from aquatic, algae-like plants by evolving:
-Formation of an embryo
-Ability to stand upright and grow
-Vascular tissues to transport nutrients, water, and waste
-Strategies to reduce water loss
-Strategies to disperse reproductive structures without water current

Question 4

Fossil and biochemical evidence indicate;
______________ are the oldest group of plants
__________ the youngest

Answer 4

green algae; flowering plants

Question 5

oldest evolved plants to newest evolved plants

Answer 5

green algae
mosses & relatives
ferns & relatives
cone-bearing plants
flowering plants

Question 6

vascular plants - sexual reproduction

Answer 6

-spores
-seeds not enclosed in fruit (gymnosperms)
-seeds enclosed in fruit (angiosperms)

Question 7

alternation of generations

Answer 7

-most plants have a life cycle that alternates
between diploid and haploid forms

Diploid = 2 sets of chromosomes
Haploid = 1 set of chromosomes

Question 8

____________________________ produces egg and sperm cells called gametes

Answer 8

Haploid generation (gametophyte)

Question 9

______________________ produces spores

Answer 9

Diploid generation (sporophyte)

Question 10

Conifers

Answer 10

-Conifers also go through alternation of generations
-They have two separate cones, male and female, that are the gametophytes
-Zygote produces a seed
-Sporophyte is dominant

Question 11

spores

Answer 11

-haploid but they can develop into a new organism
-can develop tough coats that enable them to persist in unfavourable conditions

Question 12

gametes

Answer 12

are haploid so they must fuse with another gamete to form a zygote (that is now diploid)

Question 13

true or false: Sporophytes are usually the dominant generation (*except for mosses)

Answer 13

true

Question 14

major groups of plants

Answer 14

5 groups:
Green algae
Mosses
Ferns
Seed plants
Flowering plants

Question 15

green algae is found in _________ around edges of __________

Answer 15

shallow freshwater; ponds and lakes

Question 16

green algae have

Answer 16

cell walls and photosynthetic pigments

Question 17

green algae are modern relatives of ______

Answer 17

plant ancestors

Question 18

true or false: algae undergo alternation of generations

Answer 18

false

Question 19

mosses

Answer 19

seedless non-vascular plants

Question 20

mosses are the first to branch off from ___________

Answer 20

aquatic ancestors

Question 21

true or false: mosses don’t have seeds, stems, or rigid support structures

Answer 21

true

Question 22

because mosses are non-vascular, they are ____

Answer 22

short

Question 23

in mosses, _______ are the dominant generation, called ________

Answer 23

gametophytes; bryophytes

Question 24

true or false: in mosses, sperm and eggs are produced in the same structure

Answer 24

false… separate structures

Question 25

in mosses, how do sperm get to eggs?

Answer 25

they're flagellated and must swim through water to meet eggs

Question 26

ferns

Answer 26

seedless vascular plants

Question 27

ferns have vascular tissue, therefore they are _____

Answer 27

taller

Question 28

what is the dominant generation in ferns?

Answer 28

sporophyte

Question 29

what is the gametophyte called in ferns?

Answer 29

prothallus

Question 30

gametophyte in ferns has ________________ structures

Answer 30

sperm and egg producing structures

Question 31

true or false: in ferns, sperm are flagellated

Answer 31

true

Question 32

where are spores found in ferns?

Answer 32

on the underside of the sporophyte leaf

Question 33

seed plants

Answer 33

gymnosperms

Question 34

gymnosperms are ______ and contain ___________

Answer 34

vascular; “naked” seeds

Question 35

true or false: gymnosperms are protected in an ovary

Answer 35

false

Question 36

examples of gymnosperms (seed plants)

Answer 36

Ex. Pine, spruce, fir, cedar

Question 37

seeds

Answer 37

plant embryos packaged in a protective coat with a food supply

Question 38

tree

Answer 38

Highly developed diploid sporophyte

Question 39

in gymnosperms, where do gametophytes live

Answer 39

Gametophytes live in the cones on the sporophyte

Question 40

pollen

Answer 40

small male gametophytes (which don’t require water to move)

Question 41

which group was the first to have seeds

Answer 41

gymnosperms

Question 42

flowering plants

Answer 42

angiosperms

Question 43

“Enclosed seed” =

Answer 43

inside an ovary

Question 44

what was the last group to evolve

Answer 44

angiosperms

Question 45

what does flowering plants coincide with in terms of evolution?

Answer 45

Coincides with rise in mammals in animal kingdom

Question 46

what are the reproductive structures in angiosperms?

Answer 46

flowers

Question 47

why are angiosperms the most effective?

Answer 47

Most effective, use animals to transport

Question 48

how did flowers evolve?

Answer 48

Flowers evolved as a mechanism to hold the gametophytes, and protect and disperse the seed (via fruit)

Question 49

Flowers are designed to _______ animals/insects to ______ and _______ seeds

Answer 49

attract; pollinate; disperse

Question 50

Change in plant growth and rainforest destruction can affect ...

Answer 50

precipitation, weather patterns, and microclimates

Question 51

plants and rainforests can eventually repair themselves (to an extent) IF ...

Answer 51

negative human impacts cease

Question 52

What differentiates a plant from the species of other kingdoms?

Answer 52

* Plants are eukaryotic. * Plants have cell walls that contain the carbohydrate cellulose. * Plants carry out photosynthesis, using the pigment chlorophyll to transform sunlight into chemical energy

Question 53

A plant lives in two environments:

Answer 53

air and soil

Question 54

what do plants use to transform sunlight into chemical energy for photosynthesis

Answer 54

chlorophyll

Question 55

What group of algae is most closely related to plants?

Answer 55

green algae

Question 56

evolution of plants diagram

Answer 56

-plant ancestor Green Algae -embryo formation Mosses and Relatives -true water-conducting tissues Ferns and Relatives -seeds Cone Bearing Plants -flowers: seeds enclosed in fruit Flowering Plants

Question 57

Why must a bryophyte have open water to be successful?

Answer 57

The bryophytes do not have any rigid support structures, such as lignin-reinforced cell walls or vascular tissues, that allow most modern terrestrial plants to stand tall and transport water great distances upward against the force of gravity to leaves and shoots this is why they need to be close to the ground near water to be successful and survive

Question 58

what is lignin?

Answer 58

a chemical that hardens cell walls, allowing them to stand upright

Question 59

which group of plants represent these today: Primitive plants lacking leaves, stems, seeds, or any rigid tissue evolve from algal ancestors and begin to colonize areas where water and land meet

Answer 59

mosses

Question 60

which group of plants represent these today: Plants begin to develop lignin, a chemical that hardens cell walls, allowing them to stand upright, and vascular tissues to transport water and nutrients. This allows plants to move farther away from water bodies

Answer 60

ferns

Question 61

which group of plants represent these today: The development of seeds, plant embryos encased in a protective covering along with a food supply, helps plants spread to diverse terrestrial habitats by allowing plant embryos to be dispersed without drying out.

Answer 61

seed plants (gymnosperms)

Question 62

which group of plants represent these today: The final major period of plant evolution begins with the appearance of flowering plants. Flowers are a reproductive structure that attracts animals to help spread plants’ seeds farther afield

Answer 62

flowering plants (angiosperms)

Question 63

What is the function of the vascular tissue in plants?

Answer 63

transport water and nutrients, allows plants to be taller

Question 64

Vascularization

Answer 64

Vascularization, the formation of tubes to carry fluid throughout an organism, was the next step in plants’ invasion of land, allowing plants to reach greater heights by connecting above-ground shoots and underground roots

Question 65

What resources are necessary for a plant to grow?

Answer 65

sun, water, height (capture more sunlight=more successful)

Question 66

Today, biologists divide seedless vascular plants into three phyla:

Answer 66

ferns, club mosses, and horsetails

Question 67

Why are plants considered the foundation of most ecosystems?

Answer 67

Plants form the critical base of food chains in nearly all ecosystems. Through photosynthesis, plants harvest the energy of the sun, providing both food and habitat for other organisms.

Question 68

Why are green algae but not brown algae considered part of the plant kingdom?

Answer 68

green algae have cell walls and photosynthetic pigments identical to plants and brown algae do not

Question 69

Which group of plants appears to be the most successful? Justify your answer

Answer 69

angiosperms because their seeds are protected in ovaries (flowers) and their seeds (ovary develops into fruit) get dispersed by other animals

Question 70

Most plants have roots, but mosses do not. Name and describe the function of the underground growth in mosses

Question 71

Why can ferns grow several metres tall but mosses cannot?

Answer 71

because of vascularization and mosses don't have it Vascularization, the formation of tubes to carry fluid throughout an organism, was the next step in plants’ invasion of land, allowing plants to reach greater heights by connecting above-ground shoots and underground roots

Question 72

List two key adaptations that distinguish angiosperms from earlier plants

Answer 72

seeds enclosed in an ovary (flower) ripened ovary of a flower used for seed dispersal (fruit)

Question 73

Alternation of generations is a key characteristic common to most plants. Which group of plants does not exhibit this life cycle?

Answer 73

green algae

Question 74

Describe the process of alternation of generations.

Answer 74

spores(n) --> gametophyte plant(n) --> sperm(n) + eggs(n) --> fertilizaton --> sporophyte plant(2n) n - haploid 2n- diploid

Question 75

Describe the trend in gametophyte size as plants become more removed from water

Answer 75

get smaller

Question 76

Suppose you were given a plant that is haploid, small, and has flagellated sperm. What type of plant would it be? Explain how you came to this conclusion

Answer 76

fern gametophyte because mosses and ferns both have flagellated sperm but because ferns evolved later than mosses, their gametophytes are smaller

Question 77

Why is the gymnosperm seed a less successful reproductive strategy than the angiosperm seed?

Answer 77

because on days when there's no wind, the seeds don't get dispersed but for angiosperms, the seeds are in fruit and they attract animals that disperse them

Question 78

Why is the dispersal of the seed a key factor in the success of angiosperms?

Answer 78

attracts animals that disperse the seed for it

Question 79

Suppose a bacterium that targets the production of lignin tissue were to infect all plants. How might this affect the evolution of future plants?

Answer 79

lignin is a chemical that hardens cell walls, allowing them to stand upright -without lignin, none of the plants would be tall or able to stand on their own, and would affect plant growth and development, which could lead to a decrease in plants

Question 80

Describe how deforestation can contribute to climate change

Answer 80

-rainforests get their name from all the water vapour in the air around them. -much of this water vapour becomes precipitation. -thus, changes in plant growth and destruction of rainforests can alter precipitation and weather patterns.