lecture 7 (Haptophytes)

Question 1

in what type of environment are haptophytes most abundant?

Answer 1

low nutrient waters, also polar, subpolar and temperate oceans

Question 2

what is the other name for haptophytes?

Answer 2

prymnesiophytes

Question 3

briefly describe the fossil record of haptophytes

Answer 3

best fossil record among algae due to the calcium carbonate plates. calcite coccoliths are well preserved in sediments

Question 4

what is a haptonema and how is it different from a flagellum?

Answer 4

a filamentous appendage that emerges between the flagella. can be short or long.
different from a flagella because it can’t beat. it bends and coils

Question 5

describe the function of a haptonema (3)

Answer 5

feeding: bending -> phagotrophic behaviour
collision avoidance: coiling -> sensory response to obstacles
attachment to substrates

Question 6

what means of locomotion do haptophytes have?

Answer 6

2 smooth, equal flagella

Question 7

name the different kinds of coccoliths that coccolith bearing haptophytes can have. describe differences in development

Answer 7

holococcoliths -> organic scales produced by golgi aparatus, secreted to the outside. calcite is deposited externally as tiny crystals that don’t interlock (messier)
heterococcoliths -> organic scales and calcite are deposited internally with the crystals and coccoliths interlocking

Question 8

which motile haptophyte does not have a haptonema

Answer 8

genus Emiliana

Question 9

what are coccoliths made of and what is the function?

Answer 9

calcium carbonate
function = focus light into cells, protection from photodamage, protection from pathogens, protection against grazing, buoyancy regulation, protection from physical damage

Question 10

what genus of haptophyte produces slime accumulation on some beaches?

Answer 10

Phaeocystis

Question 11

why would coccolithophorids be more severly affected by ocean acidification than other unicellular algae?

Answer 11

they use calcium carbonate coverings which are harder to form/dissolve in acidic oceans

Question 12

what colour are coccolithophorid blooms when seen from space?

Answer 12

white (the calcium carbonate)

Question 13

do oceans with coccolithophores or oceans with diatoms have higher carbon drawdown? why?

Answer 13

diatoms, since formation of calcium carbonate uses some CO2, it slows the rate of PP and carbon drawdown in coccolithophoric oceans

Question 14

what are the equation(s) that represent the process of calcification? what connection is there between calcification and photosynthesis?

Answer 14

calcification:
CO2 + Ca+ H2O -> CaCO3 + 2H
calcification is dependent on photosynthesis for ATP and NADPH
photosynthesis does not depend on calcification for CO2

Question 15

what is the net calcification equation(including HCO3 utilization)?

Answer 15

2HCO3+Ca-> CaCO3 + CO2 + H2O

Question 16

why did we talk about the white cliffs of dover and the isle of wight during the Haptophyte lecture?

Answer 16

because the coccoliths of this alga have created these characteristic chalky white cliffs

Question 17

describe the plastids and pigments in haptophytes

Answer 17

butterfly shaped plastids with 4 membranes
chl a, chl c, carotene, xanthophylls (eg. fucoxanthin, diadinoxanthin)

Question 18

describe the storage molecule in haptophytes

Answer 18

chrysolaminaran polysaccharide (stored in vacuoles)

Question 19

draw the life cycle of Emiliania huxleyi

Answer 19

diploid vegetative asexual cell division, also can produce haploid gametes covered with holococcolith scales which can also undergo asexual haploid vegetative cell division or fuse to form a diploid zygote which becomes the diploid vegetative cell with heterococcoliths. zygotes have holococcoliths and heterococoliths

Question 20

which life stage has heterococcoliths

Answer 20

diploid stages (and zygote)

Question 21

which life stage has holococcoliths

Answer 21

haploid stages (and zygote)

Question 22

which life stage has hetero and holococcoliths?

Answer 22

the zygote

Question 23

describe ecological and climatic importance of haptophytes

Answer 23

good source of fatty acids, can produce toxins/harmful substances, dense blooms, huge part of carbon cycle, sediment formation, and releases DMS

Question 24

what is DMS and how is it important for climate?

Answer 24

dimethyl sulfate, volatile organic sulfur gas, a defense from UV radiation. it contributes to acid rain, cloud formation, albedo

Question 25

Describe the DMS cycle

Answer 25

UV radiation, causes more DMS to be released, increasing clouds, and causing a cooling effect?
DMS enhances cloud formation by acting as a nucleus, the increase in clouds increases albedo, reflecting sun back. DMS can be taken into these clouds and rain down as acid rain.

Question 26

an uncalcified genus of haptophyte used in aquaculture

Answer 26

pavlova, unicellular flagellate also in palmelliod stages

Question 27

uncalcified haptophye genus that forms large gelatinous colonies, producing 10% of global flux of DMS to amosphere

Answer 27

phaeocystis

Question 28

single celled haptophyte that produces toxins that kill fish

Answer 28

prymnesium

Question 29

marine and freshwater haptophyte with ameboidal stages that have toxins that kill fish in marine and odor and tadpole deaths in freshwater

Answer 29

chrysochromulina

Question 30

calcified coccolithophore which forms dense blooms, no toxins, lacking haptonema

Answer 30

Emiliana