Chapter 4

Question 1

Give the general equation for photosynthesis

Answer 1

6CO2 + 6H2O + LIGHT ENERGY = C6H12O6 + 6 O2

Question 2

what are the 2 basic reactions to photosynthesis, and where do they occur?

Answer 2

Light reaction: occurs in thylakoids. Splits water, release oxygen, produce ATP and NADPH

The Calvin Cycle: occurs in the stroma and cytosol. forms sugar from CO2, using ATP for energy and NADPH for electrons.

Question 3

If seaweed appears to be red to us, what colors are being absorbed and which are reflected?

Answer 3

reflecting red light and absorbing blue light

Question 4

what are the three categories of pigments that algae use?

Answer 4

chlorophylls, carotenoids, phycobiliproteins

Question 5

Chlorophylls:

Answer 5

water insoluble, fat/lipid soluble. non-polar

Question 6

Carotenoids:

Answer 6

water insoluble, fat/lipid-soluable (non polar)
carotene (red-orange), xanthophylls (brown-yellow)
fucoxanthin, diadinoxanthin, peridinin

Question 7

Phycobiliproteins:

Answer 7

water soluble, fat insoluble (polar)

phycocyanin (blue-green) phycoerythrin (red)

Question 8

photosynthesis:

Answer 8

converts solar energy into chemical energy

Question 9

who are the producers of marine ecosystems?

Answer 9

algae and seagrasses

Question 10

who are the producers of fresh water ecosystems?

Answer 10

algae and macrophytes

Question 11

what are the three components of a chloroplast?

Answer 11

thylakoids, grana, stroma

Question 12

where does the light reaction occur?

Answer 12

in the thylakoids

Question 13

where does then calvin cycle occur?

Answer 13

in the stroma or cytosol (blue green algae in cytosol, b/c of no thylakoids)

Question 14

which has less energy, long or short waves?

Answer 14

long wavelengths

Question 15

PAR

Answer 15

photosynthetically active radiation

Question 16

why cant you see shadows under water?

Answer 16

because water is light scattering

Question 17

what angle of incidence is critical for 100%?

Answer 17

90degrees

Question 18

what three things can happen when light meets matter?

Answer 18

absorb, reflected, transmitted

Question 19

Pigments:

Answer 19

substances that absorb visible light

Question 20

what measure of wavelength has the most transmittance?

Answer 20

550nm

Question 21

how can algae respond to low/high light levels?

Answer 21

can produce more/ lose pigments, or create protective pigments

Question 22

What is the photosystem comprised of?

Answer 22

a reaction center surrounded by a number of light harvesting complexes

Question 23

what are the ‘light harvesting complexes’ found within the photosystem?

Answer 23

pigment molecueles bound to particular proteins, who funnel energy to reaction center.

Question 24

name some types of chlorophyll pigments:

Answer 24

a, b, c1, c2, d

Question 25

name some types of carotenoid pigments

Answer 25

carotene (red-orange), xanthophylls (brown-yellow), fucoxanthin, diadinoxanthin, peridinin

Question 26

name some phycobilliprotein pigments

Answer 26

phycocanin (blue-green), phycoerythrin (red)

Question 27

what is chromatic adaptation?

Answer 27

the ability to adjust their concentration of pigments. Respond to high vs low light, tremendous phenotypic plasticity

Question 28

what are the three G’s of algae photosynthetic products?

Answer 28

Glucose polymers: amylose, starch, cellulose
Glucans: laminarin, chrysolaminarin
Galactans: agar, carageenan

Question 29

How deep can you find Rhodophyta?

Answer 29

in over 800m of water

Question 30

Whad to you call a short daylight photoperiod responce?

Answer 30

foliose phase

Question 31

what do you call a long daylight photoperiod responce?

Answer 31

conchocelis phase

Question 32

Photoautotroph

Answer 32

use the energy of sunlight to make organic molecules from water and carbon dioxide

Question 33

Chloroplasts:

Answer 33

organelles of photosynthesis consist of thylakoids, grana, stroma

Question 34

Pigments:

Answer 34

cubstances that absorb visible light (phycobilliproteins, carotenoids, chlorophylls)

Question 35

Acessorty Pigments:

Answer 35

Absorb different wavelengths of light and pass the energy to chlorophyll-a

Question 36

Photoperiod responses:

Answer 36

control some aspect of a life cycle by the timing of light and darkness

Question 37

what are the three phases that occur in the STROMA?

Answer 37

• carbon fixation (adding carbon from carbon dioxide to a molecule)
• Reduction: (addition of electrons from ATP and NADPH molecules)
• REGENERATION of the CO2 acceptor molecule

Question 38

Absorption spectrum

Answer 38

The range of frequencies of electromagnetic radiation readily absorbed by a substance by virtue of its chemical composition

Question 39

Photic Zone

Answer 39

is the depth of the water in a lake or ocean that is exposed to sufficient sunlight for photosynthesis to occur.

Question 40

Reaction Center

Answer 40

Surrounded by several light harviesting complexes, the reaction center is an organized association of proteins holding a special pari of chlorophyll molecules.

Question 41

Cyclic Electron Flow

Answer 41

a route of electron flow during the ight reactions of photosynthesis that involves only photosystem 1 and that produces ATP but not NADPH or O2

Question 42

ATP synthase

Answer 42

a complex of several membrane proteins that functions in chemiosmosis with adjacent electron transport chains, using the energy of a hydrogen ion concentration gradient to make ATP. ATP synthases are found in the inner mitrochondrial membranes of eukaryotic cellls and in the plasma membranes of prokaryotes.

Question 43

Carbon Fixation

Answer 43

the initial incorporation of carbon from CO2 into an organic compound by an autotroic organism ( a plant, another photosynthetic organism, or a chemoautotrophic prokaryote).