Plants

Question 1

What is biodiversity?

Answer 1

The variety of life, in all its manifestations. It encompasses all forms, levels and combinations of natural variation.

Question 2

How much biomass - excluding microbes - do plants represent?

Answer 2

90%

Question 3

What do Plants provide for humans?

Answer 3

Feed us, provide drugs, materials for clothing and building, one of our main sources of fuel - living and dead

Question 4

For how much of Earths history was the land face largely lifeless?

Answer 4

3000my

Question 5

When did plants begin to colonise land?

Answer 5

500mya

Question 6

When did plants evolve to grow tall, leading to the first forests?

Answer 6

370mya

Question 7

How many known plant species are there?

Answer 7

> 290 000

Question 8

How do plants enable other forms to exist successfully on land?

Answer 8

Roots provide habitats by anchoring the soil, supply oxygen and provide food for terrestrial

Question 9

What key characterises are shared by plants and protists?

Answer 9

multicellular eukaryotes, photosynthetic autotrophs

Question 10

What else, other than plants have cell walls made of cellulose?

Answer 10

Green algae - charophytes and dinoflagellates

Question 11

What are charophytes?

Answer 11

Division of freshwater green algae, possibly closest relative to land plants.

Question 12

What similarities to charophytes and green algae share?

Answer 12

Rosette shaped cellulose, Peroxisome enzymes, Formation of phragmoplast, Structure of flagellated sperm

Question 13

How are protein arrays arranged in non charophyte algae?

Answer 13

Linear

Question 14

Describe what is meant by Rosette shaped cellulose

Answer 14

Cells have circular petal shaped arrays of protein on the plasma membrane, which synthesise cellulose microfibrils

Question 15

What is the phragomplast?

Answer 15

Mechanism in plant and charophyte cell division, forms during late cytokinesis, a group of microtubules that form between the dividing nuclei acts as a scaffold for forming cell plate

Question 16

Where do charophytes live?

Answer 16

shallow waters at the edge of ponds and lakes

Question 17

How did natural selection in the habitat of charophytes lead to the evolution of land plats?

Answer 17

Live in habitats that may dry out, so selection favours plants that can withstand long periods out of the water.

Question 18

What feature do charophytes have to protect their zygote when dry?

Answer 18

Strong sporopollenin walls

Question 19

What are the benefits of moving onto land?

Answer 19

Bright, unfiltered sunlight, more plentiful CO2, soil rich in minerals and nutrients, relatively few herbivores

Question 20

What were the physiological problems did plants have to overcome moving onto land?

Answer 20

Water balance, Availability of essential nutrients and gases, Support, UV protection, reproductive strategy

Question 21

How did plants adapt to limited water availability on land?

Answer 21

No longer bathed in water, had to use rhizoids/Roots, xylem, cuticle and stomata

Question 22

How did plants adapt to obtain nutrients and gases on land?

Answer 22

Collect from soil and atmosphere using roots and stomata

Question 23

How did plants adapt to support on land?

Answer 23

use lignified conducting tissues

Question 24

How did plants adapt to UV protection on land?

Answer 24

use of a cuticle

Question 25

How did plants adapt their reproductive strategy for life on land?

Answer 25

protected by sporopollenin, dispersal by new vectors

Question 26

What are the derived traits shared by plants?

Answer 26

Alternation of generations and multicellular dependent embryo Walled spores produced in Sporangia Multicellular Gametangia Apical Meristems

Question 27

What is alteration of generations?

Answer 27

Lifecycle alternates between multicellular haploid organisms and multicellular haploid organisms, each generation gives rise to the other

Question 28

What is the diploid generation called?

Answer 28

Sporophytes

Question 29

What is the haploid generation called?

Answer 29

Gametophyte

Question 30

Why was the haploid stage named gametophyte?

Answer 30

Named because it is the gamete producing plant, production of haploid gametes by mitosis.

Question 31

How is the diploid sporophyte formed?

Answer 31

Fertilisation of haploid gametes, diploid zygote is created, mitotic division of zygote leads to new sporophyte plant

Question 32

Why is the diploid stage named sporophyte?

Answer 32

Meiosis is a mature sporophyte produces haploid spores, that can develop into a new haploid organism with mitosis

Question 33

Where do multicellular embryos develop?

Answer 33

In the tissues of female gametophyte, from zygotes. The parent tissue provides nutrients via special placental transfer cells

Question 34

What are plant spores?

Answer 34

Haploid reproductive cells that can grow into multicellular haploid gametophytes

Question 35

What polymer makes walls of spore tough and resistant?

Answer 35

Sporopollenin

Question 36

What does sporopollenin allow plants to do?

Answer 36

Disperse spores through dry air without harm

Question 37

Where are spores produced?

Answer 37

On the sporophyte, in multicellular organs called sporangia

Question 38

How are spores made in the sporangia?

Answer 38

Diploid cells called sporocytes undergo meiosis and generate haploid spores

Question 39

What are the differences in the way charophytes and sporophyte produce their pores?

Answer 39

No multicellular sporangia in charophytes, and their spores lack sporopollenin

Question 40

Where are the gametes in plants produce?

Answer 40

Gametangia

Question 41

What are the female gamentangia called?

Answer 41

Archegonia

Question 42

Describe the archegonia

Answer 42

Pear shaped organs that produce a single non motile egg, retained in the bulbous part of the organ.

Question 43

What are male gametangia called?

Answer 43

Antheridia

Question 44

Describe the antheridia

Answer 44

Produce sperm and release them into the environment.

Question 45

How does the sperm reach the eggs in many modern day plants?

Answer 45

Have flagella and swim to the eggs through water droplets.

Question 46

What are the essential resources plants have to gain from their surroundings?

Answer 46

Co2, Light, Water, minerals and nutrients

Question 47

What are apical meristems?

Answer 47

Localised regions of cell division at the tips of roots and shoots.

Question 48

What are secondary compounds?

Answer 48

products of secondary metabolic pathways

Question 49

What are the secondary products in plants?

Answer 49

alkaloids, tamarins, Flavinoids

Question 50

What are non vascular plants called?

Answer 50

Bryophytes

Question 51

What are vascular plants Called?

Answer 51

Tracheophytes

Question 52

What are the distinguishing features of bryophytes?

Answer 52

Conducting tissues not lignified, gametophyte dominant with sporophyte subsidiary.

Question 53

What are the distinguishing features of sporophytes?

Answer 53

Conducting tissues lignified, sporophyte dominant, with gametophyte subsidiary.

Question 54

What is the plant kingdom known as?

Answer 54

Embryophta

Question 55

What are the three classes in the division Bryophyta?

Answer 55

Hepatics - Liverworts, Musci - mosses, Anthocerotes - Hornworts

Question 56

What are the throw classes of tracheophytes?

Answer 56

Pteridophytes, Gymnosperms, Angiosperms

Question 57

What are the orders of pteridophytes?

Answer 57

Lycopsids, Spenopsids, Ferns

Question 58

What are the orders of Gymnosperms?

Answer 58

Cycads, conifers, conifers, ginkgos, genetales