Test 1 Flashcards
Plant blindness
“the inability to see or notice the plants in one’s own environment,” which leads “to the inability to recognize the importance of plants in the biosphere and in human affairs”
An “inability to appreciate the aesthetic and unique biological features” of plants
Monoecious
both sexes/parts in one flower/on one plant
MOST PLANTS
mono = one
ecious = house
Dioecious
separate sexed plants
SMALL proportion of plants
di = two
ecious = house
Male flowers release pollen to fertilize female flower parts
Female plants make seeds/fruit
5 very urban tolerant tree species
- Ginkgo biloba = ginkgo (aka “silver apricot”)
- Ulmus americana = american elm
- Zelkova serrata = japanese zelkova
- Gleditsia triacanthos var. inermis = thornless common honeylocust
- Platanus ×acerifolia = london planetree
Ginkgo biloba
silver apricot
DIOECIOUS
Ripe fruit (FEMALES) smells like vomit
SOLUTION: avoid smelly fruit by planting MALE trees
superb yellow fall foliage color
Ulmus americana
american elm
extremely urban tolerant
ideal street tree
opposing vase-shaped trees create cathedral-like ceiling
dutch elm disease (DED)
lethal funcus spread by beetle
NOW WE HAVE DISEASE-RESISTANT TYPES
treatment w fungicide effective in advance of disease/if tree is in early stage of infection
Zelkova serrata
japanese zelkova
vase shape
Gleditsia triacanthos var. inermis
thornless common honeylocust
SOME species have thorns
this is the THORNLESS variety
Platanus ×acerifolia
london planetree
hybrid of 2 species US + Asian
urban tolerant
grow near/in sidewalk
showy, patchy cream-tan-brown bark
Important campus oak species
Quercus macrocarpa = bur oak
Quercus macrocarpa
Bur oak
NOT a typical urban tree species
IN FRONT OF BURRUSS HALL
(we don’t call it Burruss Hall bc of the burr oak)
macro = big
carpa = fruit
bur = rough, prickly case around seeds/nuts
fringe around the nut
Photosynthesis
converting carbon in the air into sugar
Carbon in the air = carbon dioxide (CO₂)
LIGHT/SOLAR ENERGY IS CONVERTED TO CHEMICAL ENERGY (ATP & NADPH)
CHEMICAL ENERGY IS STORED IN THE FORM OF GLUCOSE (sugar)
BASIS OF FOOD CHAIN
Provides virtually all the energy source for all organisms
2 main parts of photosynthesis
- Light reactions
- Dark reactions
calvin cycle
sugar production
air concentrations
Carbon dioxide (CO₂) = 0.04%
420 ppm (parts per million)
Nitrogen (N₂) = 78%
Oxygen (O₂) = 20.9%
where photosynthesis takes place
chloroplasts
thylakoid membrane
contains chlorophyll (photosynthetic pigments)
part 1 of photosynthesis
light reactions
LIGHT/SOLAR ENERGY IS CONVERTED TO CHEMICAL ENERGY (ATP & NADPH)
2 forms of chemical energy (HIGH ENERGY compounds/MOLECULES) formed in light reactions
1. ATP (adenosine triphosphate)
Contains a large amount of energy in third phosphate bond
ADP (adenosine diphosphate) is a LOW energy compound
2. NADPH
NADP⁺ gains electrons & proton → NADPH
NADP⁺ is a LOW energy compound
electromagnetic radiation
light = form of electromagnetic radiation
short waves = high photon energy
long waves = low photon energy
visible light range
wavelengths 400 nm - 700 nm
photosynthetically active radiation (PAR)
peaks in blue & red
leaves are green bc blue & red are absorbed & green is reflected
2 main photosynthetically active pigments
chlorophyll A & chlorophyll b
part 2 of photosynthesis
CHEMICAL ENERGY IS STORED IN THE FORM OF GLUCOSE (sugar)
Calvin cycle - uses energy rich molecules from light reactions (ATP & NADPH) & CO₂ to produce sugars
Chemical energy to fix CO₂ into sugar
Carboxylation (aka carbon fixation) - addition/insertion of CO₂ to an organic molecule
Rubisco - enzyme that incorporates CO₂ into the Calvin cycle
Catalyzes a 5-C (RuBP) + CO₂ reaction
Links 5-C & CO₂ to make 6-C
Responsible for carbon fixation
CATALYST = increases reaction rate
6-C quickly splits into two 3-C molecules
Split by ATP
3-C molecules are STABLE
Photorespiration
RUBISCO ALSO reacts w oxygen (O₂) INSTEAD OF fixing CO₂
THIS IS BAD bc it wastes carbon & energy
Wasted energy from high energy compounds (ATP, NADPH) converted to low energy NADP
Wasted carbon from CO₂ is NOT FIXED → NO GLUCOSE MADE
C-3 plants
The first stable molecules formed after carbon fixation have 3 carbon atoms
Air spaces between cells w chloroplasts CAUSE PHOTORESPIRATION
Mesophyll cells are exposed to oxygen → photorespiration
RUBISCO ALSO reacts w oxygen (O₂) INSTEAD OF fixing CO₂
About 95% of all C-3 species are subject to photorespiration
C-4 plants
Mesophyll cells are arranged in one layer that surrounds the vascular bundle & bundle sheath cells
Mesophyll cells DO HAVE chloroplasts BUT do NOT have calvin cycle
Bundle sheath cells DO HAVE chloroplasts & calvin cycle
Have different anatomy/metabolism to AVOID PHOTORESPIRATION
Bundle sheath cells are NOT exposed to oxygen → calvin cycle NOT exposed to oxygen → NO photorespiration
