9 marine organisms

8/12/2019 9 Marine Organisms

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Common Marine Organisms1

Common Marine Organisms

Purpose of this lab: The purpose of this lab exercise is for you to observe and becomefamiliar with specimen of marine algae and common invertebrate marine organisms.

Assignment Objectives: 1.) Be able to identify the algae lab samples to the level of

phylum; 2.) Be able to recognize the marine invertebrate samples by common name anto the specific level discussed during lab; 3.) Classify the marine organisms based on

habitat, transportation, and feeding styles.

Part 1 Algae and PlanktonKingdom Protista contains organisms that are more closely related to members of otherkingdoms than they are to other protists. It is also defined on the absenceof characters

(i.e. no complex development from embryos, no extensive cell differentiation). Recent

studies of protist DNA and structure has shown that the protists are far more diversethan had been previously expected; they probably should be classified in severalkingdom-level taxa. The word protist is a convenient term to mean "eukaryote that isn't

a plant, animal, or fungus." (See UCMP Eukaryota: Systematics, for more information

on protist classification).

Kingdom Protista: AlgaeThe key to habitats for marine algae is light for photosynthesis. Besides light, other

physical conditions that allow alga growth and reproduction are water quality and

temperature, availability of carbon and other nutrients, and seafloor depth or tidalexposure. The alga inhabiting shallow coastal areas (the intertidal and subtidal zones)also must contend with forces relating to wave motion. Almost all marine algae (except

algal plankton) are benthic, attached to the sea floor or a solid substrate such as a reefor rocks.

There are three phyla of marine algae: Phylum Chlorophyta(green algae), PhylumRhodophyta(red algae), and Phylum Phaeophyta(brown algae). The colors of the

algae vary due to different pigments that the algae use to convert sunlight into chemicalenergy via photosynthesis. While all algae have chlorophyll pigments, red algae also

have red and blue pigments, and brown algae also have orange pigments.


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Phylum Chlorophyta

Algae in this phylum are more closely related to land plants than the other

photosynthetic protists. Because they do not have many of the adaptations to land

environments that plants share, they continue to be classified as green algae in theKingdom Protista. Land plants arose from within this group.

a. b.

Both photos a. and b. show the chlorophyte genus Ulva. This type of chlorophyte algae

is commonly called sea lettuce, and looks like bright green sheets.(Photos: a. MBARI, b. UCMP)


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Phylum Rhodophyta

Most red algae are multicellular and grow attached to rocks or other anchorages. The

coralline algae secrete calcium carbonate (CaCO3) in their cell walls and form a rigid,branching structure. Other varieties of rhodophytes have a thin sheet appearance, or

encrust rocks or other surfaces.

a.

b.

a.) Rhodophyte (Mastocarpus) common to mid-to-high intertidal zones along the

California coastb.) Coralline red algae display a branched and jointed, upright structure.Note the pink, encrusting variety on the rocks.(Photos: a. MBARI; b. UCMP)


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Phylum Phaeophyta

Phaeoophyte algae frequently dominate rocky shores in cold and temperate waters.The brown alga phylum includes the largest varieties. The giant kelp, Macrosystis

Pyrifera, forms an expansive habitat off the west coast of North America.

a.The brown alga Giant Kelp (also known as the Redwood of the ocean): Macrocystispyrifera.

b.

Giant kelp holdfast. The holdfast attaches to the seafloor, but does not uptake nutrients

and water like terrestrial plant roots.

(Both photos: MBARI)


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Seagrasses ( not algae)

Seagrasses (also known as surf grass)Grasses are vascular plants, meaning they have structures and specialized tissues

(called vascular tissue) that moves food and water from a root system throughout the

plant. Seagrasses have adapted to photosynthesis and reproduction in salt water. Theyhave a well-developed horizontal stem and air spaces that aid gas exchange andflotation of the flat leaves, and a root system that traps sediment. Seagrasses

reproduction is via pollination. Plants that reproduce by flowering are called

angiosperms.

Seagrassphyllospadix(MBARI)


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PlanktonRemember, plankton refers to a lifestyle, not a specific phylum of organism. Some

plankton are photosynthesizing protists (phytoplankton), while others are smallcarnivorous protists (zooplankton), and animals (copepods).

Phytoplankton Common phytoplankton include:

Cyanobacteria:also known as blue-green algae.

Cyanobacteria are the most ancient form of algae known to inhabit Earth, with a fossil

record over 3.5 billion years old. Cyanobacteria are single-celled, eukcaryotic algaefound as solitary cells, or in long filaments. The filamentous form can produce large

algal mats that can be attached to the sea floor.

Filamentous cyanobacteria (photos from UCMP)

Coccolithophorids:A coccolith is made of overlapping calcium carbonate (CaCO3) scales that form the cell

wall of the organism. They are very difficult to view under our microscopes because oftheir small size.

Coccolithophores(photo from NASA)


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Diatoms: single-celled or colonial organisms with cell walls made of silicon dioxide

(SiO2).Diatom shells, or tests, are typically marked with numerous holes (or areolae) visible

under the microscope. There are two body shapes, round (called centric) and long, pen-

shaped (called pennate).

a. b. c.

Solitary diatoms (photos a. and b.). View in a. shows a slice through the center of acentric diatom and the organisms radial symmetry. View b. is a side-view of a centric

diatom, with holes (areolae) visible. View c. depicts a solitary, pennate diatom.

(All diatom photos from UCMP)

Dinoflagellates:

Single-celled organisms, with a rigid outer cell covering. The organism is propelled

through the water by flagella.

Dinoflagellate: Protoperidinium crassipes(photo from Smithsonian)


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ZooplanktonZooplankton are multi-cellular animals that are classified in the Kingdom Protista. Like

phytoplankton, they also have plantonic lifestyles. Common zooplankton include:

Foraminifera:organisms with shells that are commonly divided into chambers that areadded during growth. Some simpler forms are open tubes or hollow spheres. The shell

is commonly made of calcium carbonate (CaCO3).

Foraminfera (Bolivina subaenariensis) Foraminfera (Rosalina globularis)(both Photos Ocean World)

Copepods: small crustaceans classified in Kingdom Animalia, phylum arthropoda.Other arthropods that are cousins of copepods include shrimp, and crabs, to name a

couple. Copepods have antennae and appendages that are used like paddles to movethrough the water.

Copepod(photo from MBARI)


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Part 1 Questions

Look at all algae, seagrass and plankton samples, and complete the information in thedata chart below.

Sample

Number

Classification

(e.g. phylumrhodophyta)

Description of Organism Sample Sketch

1

2

3

4

5

6

7

8

9

10


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Part 2 Classification of Marine OrganismsInvertebrates)

You will be analyzing marine organisms (mainly invertebrates) in this part of the labactivity. First, you will describe common marine invertebrates using the Linnaean

Classification System.

Linnaean Classification Scheme

Carl Linnaeus published the oldest method of describing living organisms in 1735. Hecreated a hierarchal ranking classification system that groups organisms based on their

physical similarities.All living organisms were grouped in either the plant or animalKingdoms. In this system, fungi were included with plants.

Today, the most widely used method based on Linnaeus classification scheme is the 5-

Kingdom classification system. In this system:

all prokaryotes (organisms without nuclear membranes) are placed in the

Kingdom Monera the three groups of multicellular eukaryotes are placed in separate Kingdoms,

Animalia, Fungi, and Plantae

Protista is a kingdom that includes eukaryotes that do not fit into the other

Kingdoms (discussed above in the Algae section)

The method of naming species, called binomial nomenclature, gives each species aunique, two-word Latin name consisting of genus and species names. An example is

Homo sapiens, the two-word name for humans. The figure below diagrams the seven

levels of a species name in the Linnaean Classification System:

Kingdom

PhylumClass

Order

FamilyGenus

Species

Linnaeus system needed revising to accommodate the discovery of microorganisms

after the invention of the microscope, and advancements in molecular biology and DNA

analysis. A new taxon called a domain was added to the Linnaean system. Thecategory Domain is a Superkingdom that is more inclusive than a Kingdom. Mostbiologists agree there are three domains of life on Earth: Bacteria, Archaea, andEukaryota. The Eukaryota Domain includes animals, plants, fungi and protists. The

samples you will view in lab will belong to the Eukaryota Domain, Kingdoms Protista,

Plantae, and Animalia.


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Part 2 Questions 1. Complete the table of phylum descriptionsbelow. Your textbook and

lecture notes are a good resource. Online resource:

http://www.ucmp.berkeley.edu/index.php

For phylum descriptions, list the defining traits of the organisms assigned to thisphylum (list a minimum of 2).

For phylum examples, list common organisms (2 can be listed for all but

bryozoan and porifera).

Phylum Description Examples

(common names)

Porifera

Cnidaria

Annelida

Bryozoa

Phylum Mollusca

Class: cephalopod

Phylum Mollusca

Class: gastropod

Phylum Mollusca

Class: bivalve

Arthropoda

Echinodermata

Phylum: Chordata

Subphylum:Vertebrata

! ClassOsteichthyes

Phylum: Chordata

Subphylum:

Vertebrata

! Class

Osteichthyes


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Classification of Organisms Life Habit, Transportation, and Feeding Styles

In this part of the lab you will observe and classify organisms lifestyles. You will need to

closely observe details of the samples to gather information that will help you determinehow the organism lived. An example would be observations such as fins that wouldindicate it swam.

Life Habit:

Life habit refers to where an organism lives in the ocean. The following are terms thatapply to life habits:

Pelagic- an organism lives in the open ocean water

Benthic- an organism lives on the bottom (seafloor). There are two types ofbenthic life habits:

o Epifaunal the organism lives onthe surface of the seafloor, for example

bottom fish.o Infaunal- the organism burrows intothe seafloor substrate, for example

worms.

Transportation:

Transportation refers to how the organism moves. The following are terms that apply totransportation:

Nekton the organism swims and can move themselves against a current.

Plankton the organism floats and drifts, and cannot move against a current.

Benthic Transportation

o Motile- the organism can move around on the sea floor, and is referred toas benthic motile. An example would be a lobster.

o Sessile the organism is affixed to the seafloor substrate (e.g.

barnacles), and is referred to as benthic sessile.

Feeding Styles:

Feeding styles refer to how an organism acquires food. The following are some terms

that apply to feeding styles:

Carnivore- an organism eats another organism other than algae or sea grass

Herbivore an organism eats mostly plants and algae

Filter Feeder water is pumped through an organisms cells, filtering dissolved

and suspended food. Sponges are an example of filter feeding animal.

Suspension Feeder an organism actively captures food particles from thewater (commonly with tentacles)

Deposit Feeder an organism eats detritus in muds (e.g. worms)

Scavengers organisms eat other organisms (e.g. dead organisms), but do not

hunt prey

Autotrophs organisms make their own food (e.g. by photosynthesis)


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2. Marine Organism Identification

Fill in the information in the organism identification chart below for each sample. Spendtime looking at the individual samples and describing physical traits of the organisms.These traits should help you determine the life habit, transportation and feeding styles.

SampleNo.

Phylum Organism Description &Common Name

Life Habit Transportation FeedingStyle

1

2

3

4

5

6

7

8

9

10


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Sample

No.

Phylum Organism Description &

Common Name

Life Habit Transportation Feeding

Style

12

13

14

15

16

17

18

19

20


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Questions

You should see some correlations between life habit and the other two classification

modes (feeding style and transportation).

1. If an organism has a pelagic life habit, what type of transportation stylesare most likely? List and discuss each.

________________________________________________________________

________________________________________________________________

________________________________________________________________

2. What type of transportation style is common for benthic epifaunal organisms?

What type of traits (body parts) does a benthic epifaunal organism posses that

suggests this mode of transportation? Explain your answers.

________________________________________________________________

________________________________________________________________

5. What type of feeding style is characteristic of benthic sessile epifaunalorganisms? What type of traits (body parts) might an organism possess that

would aide in this type of feeding style?

________________________________________________________________

________________________________________________________________

________________________________________________________________

6. What type of traits (body parts) might an organism possess that would aide in:

carnivorous feeding styles: __________________________________________

filter feeding: _____________________________________________________

suspension feeding: _______________________________________________

scavenging: _____________________________________________________


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References

Monterey Bay Aquarium Research Institute (MBARI):

http://www.mbari.org

NASA Earth Observatory. 2013.http://earthobservatory.nasa.gov/Features/Coccolithophores/

Ocean World. http://oceanworld.tamu.edu/students/forams/index.html

Smithsonian National Museum of Natural History. 2014.http://www.mnh.si.edu/highlight/sem/dinoflagellates.html

University of California Museum of Paleontology (UCMP). 2014.http://www.ucmp.berkeley.edu

University of California Museum of Paleontology (UCMP). 2014. Eukaryota:

Systematics. http://www.ucmp.berkeley.edu/alllife/eukaryotasy.html

9 marine organisms

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