lecture 09 - how do organisms acquire energy? autotrophs

Question 1

trophic/trophy/troph

Answer 1

having to do with food or nourishment

Question 2

autotrophy

Answer 2

make their own complex carbohydrates for nourishment from inorganic C - sources

Question 3

two types of autotrophy

Answer 3

photosynthesis and chemosynthesis

Question 4

photosynthesis

Answer 4

energy from light (converts CO2 to complex sugars) derives energy from light

Question 5

chemosynthesis

Answer 5

energy from oxidation (converts CO2 (or methane) to complex sugars) derives energy from oxidation

Question 6

heterotrophy

Answer 6

use organic sources of carbon synthesized by others to derive energy (don’t produce their own and consume other organisms)

Question 7

light

Answer 7

electromagnetic radiation (RA)

Question 8

wave-particle duality

Answer 8

radiation behaves as a wave and particle (photon)

Question 9

electromagnetic radiation

Answer 9

described as wavelengths and photon energy (amount of photons traveling in that wave)

Question 10

PAR

Answer 10

photosynthetically active radiation
quantity and quality of light influences photosynthetic rates

Question 11

what are the influences of photosynthetic rates

Answer 11

latitude (angle of solar radiation)
clouds (cloud cover)
landscape features

Question 12

what percentage of PAR is absorbed by taller plants (canopy)

Answer 12

79%

Question 13

what percentage of PAR is absorbed by the middle layer of plants

Answer 13

7%

Question 14

what percentage of PAR reaches the forest floor (low vegetation)

Answer 14

2%

Question 15

what percentage does the boreal forest reflect incoming PAR

Answer 15

10%

Question 16

what adaptation do low vegetation plants have to make up for the lack of PAR they receive

Answer 16

use portions of wavelengths not absorbed by the canopy trees

Question 17

what wavelength penetrates the water column the deepest

Answer 17

blue wavelength

Question 18

what wavelength is absorbed by the autotrophs near the surface

Answer 18

red wavelength

Question 19

what colour does the autotrophs at the surface reflect after receiving lots of the red light

Answer 19

reflect green

Question 20

what colour does the autotrophs at the deep layers reflect after receiving lots of blue light

Answer 20

reflect red

Question 21

PPFD

Answer 21

photosynthetic photon flux density

Question 22

NPR

Answer 22

net photosynthetic rate

Question 23

Pmax

Answer 23

max net photosynthesis

Question 24

max net photosynthesis

Answer 24

a limit to photosynthesis that plants can reach

Question 25

Isat

Answer 25

irradiance at saturation
the plant doesn’t have time to process any more energy intake

Question 26

LCP

Answer 26

light compensation point
less PPFD with less photosynthetic rate
light intensity at which photosynthesis = cellular respiration

Question 27

sun plant

Answer 27

achieve higher Pmax but are inefficient in using low PPFD

Question 28

shade plant

Answer 28

achieve only small Pmax but more efficient at using low PPFD
low Isat = can be damaged in sunny sites

Question 29

C3 photosynthesis

Answer 29

no separation of processes, very high photosynthetic rate, massive water loss

Question 30

C4 photosynthesis

Answer 30

anatomic separation of processes, moderate water loss, energetically costly net benefit only in high temps

Question 31

CAM

Answer 31

time separation of processes, negligible water loss, large reduction in photosynthetic rate