×

×

CCU / Math / MSCI 302 / What is the meaning of grazing in marine communities?

# What is the meaning of grazing in marine communities? Description

##### Description: This summarizes notes from chapters 3-6 and includes some possible short answer questions.
5 Pages 49 Views 1 Unlocks
Reviews

Material covered:

## What is the meaning of grazing in marine communities?

Chapter 3.3: Photosynthesis and Primary Production

I. Phytoplankton and cyanobacteria account for 95%

A. sea grass, algae, etc.

B. 40-50% of photosynthesis in the world comes from the oceans

II. Primary Production

A. production of new plant material through photosynthesis

B. gross production— total amount of organic matter

C. net production— amount of production left to support other trophic levels; amount left  after respiration

D. productivity—

1. the rate of production per unit time per area or volume

2. primary productivity— productivity due to photosynthesis

E. Measuring primary production is done through light and dark bottle experiments III. Factors that affect Primary Production:

## What is the meaning of seaweed?

1. grazing— in marine communities, grazers can occur at such high concentrations that  phytoplankton can be wiped out in a day

2. nutrients— a surplus can cause blooms

a) lowest at the surface because they are constantly used

b) silicate, nitrate, phosphate

c) regeneration— due to mixing (turbulence), upwelling, and convective mixing (due  to seasonal changes)

3. light— sufficient intensity only in limited photic zone

a) too much light can decrease photosynthesis

b) pigments that allow the most light absorption will show (ex: green , re, and brown  algae)

4. latitudes—

a) polar:

(1) highest production in summer

(2) stable, warm top layer

## What is the meaning of photosynthetic pigments?

(3) not affected by nutrients— light limited Don't forget about the age old question of What was the relationship between the us and cuba in the 1960s?

b) temperate:

(1) varies seasonally

(a) summer— lots of light

(b) spring— lots of mixing leads to high nutrients Don't forget about the age old question of What does pottery tell us about past societies?

(c) fall and winter— light decreases

(2) both light and nutrient limited

c) tropics and subtropics:

(1) abundant sun throughout the year

(2) no sediment load or nutrients= clear waters

(3) moderate increase of solar energy in the summer= small increase of  production

Chapter 4: Marine Plants

I. The Seaweeds— refers to macroscopic members of the following divisions A. multicellular plants that do not produce seeds or flowers We also discuss several other topics like What are culture specific disorders?

B. abundant on hard substrates in intertidal zones and extend 30-40 m

1. in clear waters as deep as 200 m

C. tolerate or even require surf action

D. structural features

1. lack roots, flowers, seeds, and true leaves

3. pneumatocysts— gas-filled floats

4. stipe— flexible stemlike structure

5. holdfast— attach plant to substrate

E. Photosynthetic pigments

1. Red algae— Rhodophyta

a) red plus blue phycobilin pigments and chlorophyll

(1) some appear green (ex: nori)

(2) most below low tide are soft pink to purple and red

(3) usually < 1 m

b) almost exclusively benthic

c) some are unicellular

d) 4000 species

2. brown algae— Phaeophyta

a) golden xanthophyll pigments— fucoxanthin If you want to learn more check out What would a movement from bli, what is the price of a movie ticket?

(1) combination of green and gold = olive green

b) mostly benthic

c) 1500 species

d) only type with pneumatocysts— gas filled sacs

e) largest algae— collectively known as kelp

(1) dominate temperate latitudes in benthic zones

3. green algae— chlorophyll

a) 7000 species, but only 13% are marine

b) vary in structure— filaments, flat sheets, branching forms, etc.

c) usually < 1 m

II. Anthrophyta— marine flowering plants= leaves, stems, and roots

A. abundant in localized areas along some seashores and backwater bays & sloughs B. submerged sea grass— about 60 species

C. emergent flowering plants— marsh grasses and mangals

1. marshes— intertidal grassland growing among estuariesfunctions—

(1) buffer coastlines from storm damage and erosion

(2) filter for terrestrial runoff

(3) nursery for young marine fishes and crustaceans

2. mangroves— dense thickets of tidal woodlands; over 80 species that just happen to  live at the water’s edge Don't forget about the age old question of Who translated the “a little night music,”?

a) functions—

(1) important nurseries

(2) prop roots provide substrate for benthic organisms

(3) food for a variety of organisms

(4) high primary production

(5) lots of nutrients enter primary production through decaying leaves

III. Geographic Distribution

A. only a few factors control the presence or absence

1. water and air temperature

2. tidal amplitude

3. quality and quantity of light

B. tropical western coast of Africa, west Central America, and Red Sea have impoverished  red algae

C. Southern Australia, South Africa, North Pacific, Mediterranean Sea have thriving  seaweeds

a) extensively layered forests

IV. Seasonal Patterns of Marine Primary Production

A. warm seas— tropical and subtropical

1. resembles continuous summer in temperate seas

2. abundant light and low nutrient levels

a) pycnocline blocks vertical mixing

b) compensation by year-round growing season and deep photic zone c) dinoflagellates more abundant than diatoms If you want to learn more check out What is the descent with modification?

3. upwelling areas are more productive than tropical open oceans

a) similar to coral reefs

B. Coastal Upwelling

1. replenishes nutrients in summer

2. high production as long as light is sufficient

3. duration and intensity can fluctuate with atmospheric circulation

4. Washington and Oregon— variability of spring and summer wind pattern causes  sporadic upwelling

5. Peru Current— intense upwelling year round interrupted only by el nino a) uncharacteristically warm waters around equator

C. Polar Seas

1. light is the limiting factor

a) sufficient light only lasts for a few months in summer

b) short summer diatom bloom declines rapidly

2. winter resembles that of a temperate winter, but much longer

3. melting ice containing phytoplankton initiate the bloom

4. Antarctic— upwelling

Chapter 5: Microbial Heterotrophs and Marine Invertebrates

I. Protozoans— animal-like organisms in Protista

A. unicellular and heterotrophic; loose aggregates

B. ingest food particles; no cell wall or chloroplasts

C. mostly parasitic

D. asexual reproduction

E. Sarcomastigophora

1. foraminifera— calcium carbonate shelled amoeba (internal and chambered) 2. radiolarian— internal silica shell

F. Cilophora— ciliates

1. tintinnids— most abundant

II. Fungi— saprobes

A. 1500 species are marine

B. cell wall fortified with chitin

C. saprobes— absorb nutrients from detritus and other non living organic matter III. Invertebrates— 97% of all animals

A. Porifera— sponges

B. Cnidaria— stinging animals

1. mostly marine with 10,000 known species

2. radial symmetry as either a medusa (jellyfish-like) or a polyp (sessile medusa) 3. Cnidocytes— stinging cells

a) nematocysts inside

4. Classes—

a) Scyphozoans— jellies; reduced or absent polyp stage

b) Anthozoans— sea anemones and corals; polyp form dominates

c) Hydrozoans— colonial hydra and siphonophores; ex: Portuguese man-of-war d) Cubozoans— box jellies

IV. Ctenophore— meaning “possessing ctene”

A. exclusively marine with 100 species; all are marine and planktonic B. comb jellies— ciliary combs for movement (ctenes); not very powerful nematocysts C. carnivores

D. similar to medusa form

V. acoelomates— Platyhelminthes, Nemertina, and Gnathostomulids A. Platyhelminthes

B. Gnathostomulid— jaw worms; 80 species; live in sea floor deposits C. Nermerta— ribbon worms

D. Kinorhyncha

E. Nematoda— roundworms

F. Ectoprocta

VI. Marine Coelomates

A. Mollusca— soft bodied organisms with a calcium carbonate shell either currently or  somewhere in its evolutionary history

1. Gastropoda:

2. Bivalve:

3. Cephalopoda— squid, octopus, cuttlefish, and nautilus

B. Arthropoda

1. complex exoskeleton

2. 3/4 of all organisms

3. classes—

a) merostomata— extinct water scorpions and extant horseshoe crabs b) pycnogonida— sea spiders

c) crustacea— 68,000 species

(1) decapoda— shrimp, lobster, crab

4. molting to replace shell— ecdysis

5. copepods— plaktonic crustaceans

6. barnacles— cirripedia

7. amphipod— skeleton shrimp

8. isopod— pill bugs; torso-ventrally flattened

9. euphasids— krill

C. chaetognaths

D. echinoderms— spiny skin

2. asteroidea— sea stars

3. ophiuroidea— brittle stars

4. echinoidea— sea urchins, sand dollars

5. holothiurdea— sea cucumbers

6. crinoidea— similar to brittle stars

E. chordates

1. sea squirt

2. urochordata— 3,000 species

a) tunicates

3. cephalochordata— 30 species

a) lancelets

4. vertebrates— 60,000 species

1. Distinguish between radial and bilateral symmetry:

a) better structure and orientation

b) tissues can have specific functions

c) active movement and response to external stimuli

3. What are the advantages of a closed circulatory system? 4. Why are there more osteichtyes than chondricthyes?

• bony fish have swim bladders which allows them to rest

5. Why study sharks?

• apex predators— control evolution and population size in lower trophic levels • economic value— estimated worth of \$2 million over its lifetime • intrinsic value

1. threats:

• finning

• commercial and recreational fishing

• climate change

• habitat destruction

• marine pollution

2. Why are they so vulnerable?

• slow growers

• mature late

• long gestation periods with small litters

• specific mating and nursery areas

• migratory

6. What is the CCU Shark Project? What are some of the things we catch?

Page Expired
It looks like your free minutes have expired! Lucky for you we have all the content you need, just sign up here
References: