Changing World

Question 1

Explain the Green revolution

Answer 1

• Introduced dwarfing gene
• Shorter = less straw, more grain
• Better harvest index
Improved use of fertilizers and mechanization of harvesting

Question 2

How much growth do we need per year to meet food demands?

Answer 2

2-3%

Question 3

Why do we need to increase crop yields?

Answer 3

Because we don’t hav enough table land for expansion

Question 4

Other uses for plant material?

Answer 4

Encoding proteins, produce compounds, medicine and drugs

Question 5

Explain tobacco’s use?

Answer 5

Encode proteins

Question 6

How much CO2 does photosynthesis use?

Answer 6

120 GT

Question 7

How much CO2 does plant respiration use?

Answer 7

59 GT

Question 8

How much CO2 does burning fossil fuels release?

Answer 8

7-8 GT

Question 9

How much CO2 does ocean use?

Answer 9

2 GT

Question 10

How much CO2 is missing and why?

Answer 10

2-3 GT due to storage in plants

Question 11

What is one of the most effective climate change solutions?

Answer 11

Restore 0.9 billion hectares. 2.05GT of cabron

Question 12

How do leaves respond to shade?

Answer 12

Shade = thin and broad

More sun = thicker

Question 13

How does leaf mass per unit area change in shade?

Answer 13

Sun developed is higher than shaded.

Question 14

Why did gymnosperms decline in Australia

Answer 14

Climate change
Angiosperms
Slow reproduction
Reliance on wind pollination

Question 15

What are two types of gymnosperms?

Answer 15

Cycads and conifers

Question 16

Name the 4 major families of conifers?

Answer 16

Podocarps
Araucarians
Cypresses
Taxodiums

Question 17

What are Australian native conifers?

Answer 17

Cypress pines, Wollemi pines, Podocarps

Question 18

How much of Australia is dominated by Eucalyptus and Acacia species?

Answer 18

75%

Question 19

Where does Acacia dominate?

Answer 19

Centre where rainfall is less than 300mm/year

Question 20

Where does Eucalyptus dominate

Answer 20

Areas where rainfall is above 350mm/year

Question 21

What are monocots?

Answer 21

Australian angiosperms - grasses

Question 22

What are eudicots?

Answer 22

Australian angiosperms

Question 23

What are dominant edict families?

Answer 23

Myrtaceae, proteaceae and Fabaceae

Question 24

What is special about the rot system of proteaceae?

Answer 24

Have proteome roots for low phosphorus

Question 25

What are the functional traits of plants?

Answer 25

``` Physiognomy Life span Leaf traits Root traits Photosynthetic pathway Height Leaf area index Stress tolerance Pollination ```

Question 26

What are different types of roots?

Answer 26

Nodulating and leaf traits

Question 27

What is a stress response in plants?

Answer 27

Stress response is the decrease in rate of processes

Question 28

What is acclimation in plants?

Answer 28

Phenotypic plasticity to respond to stress and improve rate of processes.

Question 29

What is adaption in plants?

Answer 29

A genotypic response to stress

Question 30

How much are crop yields reduced by stress?

Answer 30

65 to 87%

Question 31

What are the top 3 highest causes of crop loss?

Answer 31

Drought, water logging and cold.

Question 32

What is the yield gap?

Answer 32

The difference between attainable yield and actual yield.

Question 33

How have plants adapted to the cold?

Answer 33

``` Leaves are thicker Increased cell layers Increased water content Thicker cell walls Change sin cell-water potential ```

Question 34

Why does plant respiration increase with temperatures?

Answer 34

Enables supply of energy

Question 35

What are ruderals (R)?

Answer 35

Plats that invest most resources to reproduction

Question 36

What are Competitors (C)?

Answer 36

Invest more energy in leaf/stem and roots.

Question 37

What are stress tolerators (S)

Answer 37

Slow growing and morphological changes.

Question 38

How are C and R genotypes similar?

Answer 38

They both are fast growing.

Question 39

How are C and R genotypes different?

Answer 39

R species have a shorter life cycle.

Question 40

What type of cells are present in fast growing plants

Answer 40

Parenchyma cells

Question 41

What type of cells are present in slow growing plants?

Answer 41

Schlerenchyma cells

Question 42

What are the functions of roots?

Answer 42

Anchorage Uptake of nutrients and water Storage

Question 43

Types of roots

Answer 43

Prop roots, storage roots, aria roots, butters roots and air roots.

Question 44

What are stems?

Answer 44

Alternating system of nodes and internodes

Question 45

What are axillary buds?

Answer 45

They can form branches

Question 46

Name some stems?

Answer 46

Stolons, rhizomes, tubers and bulbs

Question 47

What are the three factors which influence carbon uptake?

Answer 47

Rate of photosynthesis per unit leaf area Amount of leaf area Morphology

Question 48

What influences leaf area?

Answer 48

Leaf-mass ratio | Specific leaf area

Question 49

Relationship between leaf mass and root

Answer 49

Higher LMR has smaller roots

Question 50

Benefit of increasing LMR?

Answer 50

Increases carbon gain, reduces carbon loss from small roots.

Question 51

Types of leaves in plants?

Answer 51

Tendrils, spines, storage leaves, brass and reproduction leaves

Question 52

How does primary growth occur?

Answer 52

Apical meristems divide rapidly

Question 53

How does secondary growth occur?

Answer 53

From lateral meristems

Question 54

Primary growth in monocots

Answer 54

Apical meristem is at the base of each leaf.

Question 55

How to increase crop yields?

Answer 55

Improve RGR during growth Improve RGR during stress Allocation of carbon

Question 56

What defines plant growth?

Answer 56

Increase in plant mass over time

Question 57

What happens when SLA is high?

Answer 57

Leaves are thin and light interception is increased

Question 58

Fast growing species and their relationship with SLA and LMR

Answer 58

Higher SLA and LMR

Question 59

What cells do stress tolerating species have?

Answer 59

Sclerenchyma

Question 60

Fast vs Slow growing species

Answer 60

Fast growers have more photosynthetic cells, less structural cell types Slo growers have more structural cell types

Question 61

What are the three key processes of exchanging light

Answer 61

Photosynthesis, photorespiration and respiration

Question 62

How do you calculate net photosynthesis?

Answer 62

Photosynthesis - photorespiration - respiration

Question 63

What are the conditions which favour photorespiration?

Answer 63

High temperatures | Low CO2 inside leaf

Question 64

What areas is photorespiration the highest?

Answer 64

Hot, dry areas where stomata are shut

Question 65

Where are C4 plants more productive than C3

Answer 65

In hot and dry environments

Question 66

How does water transfer occur in leaves??

Answer 66

Evapotranspiration from leaf is the drive force for water uptake from soil via the xylem.