symbiosis n.
Skip this Video
Loading SlideShow in 5 Seconds..
Symbiosis PowerPoint Presentation
Download Presentation

Loading in 2 Seconds...

play fullscreen
1 / 17

Symbiosis - PowerPoint PPT Presentation

  • Uploaded on

Symbiosis. Definition: . “To live together”… the intimate living together of two different species…. Subdivisions of symbiosis:. 1. Commensalism - . A symbiotic condition where one of the partners benefits from the interaction, while the other member is not harmed, but does

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Symbiosis' - Thomas

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript


“To live together”… the intimate living together of two different species…

Subdivisions of symbiosis:

1. Commensalism -

A symbiotic condition where one of the partners benefits from

the interaction, while the other member is not harmed, but does

not necessarily gain any advantage either…

Inquilinism is a special type of commensalism where one animal lives

in the home or digestive tract of another…

In commensalistic relationships the partner gaining the advantage

is called the commensal, and the other partner is called the host.

2. Mutualism -

A symbiotic condition where both partners benefit from the interaction.

In such mutualistic relationships, the two partners are often referred

to as the symbionts.


Subdivisions of symbiosis (cont.):

3. Parasitism -

An extreme case of symbiosis, parasitism is a condition when one partner,

the parasite, benefits from the interaction at the expense of the other

symbiotic partner, sometimes referred to as the host.

symbiosis of algae and animals
Symbiosis of Algae and Animals

Symbiotic relationships between algae and animals are typically found between

unicellular algae and their invertebrate symbiont hosts.

These relationships are most commonly seen between the algae and members of

Porifera, Cnidaria, Platyhelminthes, Mullusca, and even Protista…

The most common of these interactions is that between symbiotic dinoflagellates

(Zooxanthellae) or symbiotic chlorella (zoochlorellae), and cnidarians.

Note that the green color of the local sea anemone

Anthopleura elegantissima and A. xanthogrammica

is because of their symbiotic algae.

These individuals may have either one or both

types of the symbiotic algae (i.e. zooxanthellae

and zoochlorellae).

symbiosis of algae and animals1
Symbiosis of Algae and Animals

Algal-cnidarian symbiosis are considered to be mutualistic…So what benefit

does each symbiotic partner get from this interaction?

The cnidarian receives nutrients from the algae in form of sugars and

other basic photosynthates… in fact, some studies suggest that certain

species of cnidarians can fulfill their entire energetic requirement from

the sugars they get from their symbiotic partners...

The algae on the other hand receive cnidarian metabolic bi-products

in form of nitrates and phosphates…

This mutualistically beneficial interaction

is probably the basis for the success of coral

reefs in otherwise nutrient poor waters of

tropical oceans.

symbiosis of algae and animals2
Symbiosis of Algae and Animals

The algal-cnidarian symbiosis is a very tight relationship… The algae reside within

the endodermal cells of the cnidarians, and typically, individual cnidarians will be

associated with a million or more algae per square centimeter of tentacle tissue...

Also, the symbiotic relationship is tightly regulated, such that neither partner

Outgrows the other… in fact the entire physiology and anatomy of the symbionts

Can change following the establishment of symbiosis…

symbiosis of algae and animals3
Symbiosis of Algae and Animals

Algal cnidarian symbioses are found in a range of animals including sponges,

flatworms, and even molluscs like this giant clam…

Not all algal-animal symbioses are alike though. In some cases, the algae reside

within the cells of their hosts, whereas in other cases, they are extra-cellular.

Yet in other cases, the host individual retains only the chloroplasts of the


symbiosis of algae and animals final notes
Symbiosis of Algae and AnimalsFinal Notes

In most cases, the symbiont partners of algal-animal relationships can live without

each other (aposymbiotic); however, in nature, this is a rarity, as the symbiotic

relationship is the only way these organisms are capable of remaining “competitive”

within their environments… this is typically more vital to the animal symbiont…

Algal-animal symbioses are very tight and well regulated interactions… it is hypothesized

that similar symbiotic interactions are what gave rise to chloroplasts within plant cells…

Algal-animal symbioses are transmitted to offspring through both open and closed


Open - the juvenile animals do not have any symbions, and they get their symbiotic

partners from the environment.

Closed – algal symbionts are passes to the next generation along with the fertilized

eggs of the reproductive individuals.

symbiosis between animals
Symbiosis Between Animals

Symbiotic relationships between animals are found throughout marine systems,

but typically, these systems are not as tightly regulated as animal-algal systems.

Also, animal-animal symbioses are in many cases commensal, and in some cases

only partially mutualistic for both partners…

Types of commensal associations:

Epizoits – commensals that live on other organisms

e.g. barnacles and small snails living on larger snails…

Endozoites – commensals that live inside other animals but are not parasites

e.g. turbellarian flatworms live in the digestive tracts of larger

invertebrates and in the mantle cavity of mollusks.

symbiosis between animals other examples
Symbiosis Between Animalsother examples

On the California coast, the echiurid worm Urechis caupo builds burrows which

It “shares” with other organisms including annelid worms, shrimps, and crabs…

symbiosis between animals other examples1
Symbiosis Between Animalsother examples

Crab - sea anemone interactions seem to be common in marine systems… Can you

think of the advantages to the crabs?

Another common association is that

between anemone fish (Amphiprion sp.)

and sea anemones… Do you think this

is an example of a commensal or

mutualistic interaction?

symbiosis between animals other examples2
Symbiosis Between Animalsother examples

Another type of association is that between various fish and sea urchins…

symbiosis between animals other well known examples
Symbiosis Between Animalsother well known examples…

Pearl fish living within the

cloaca of sea cucumbers…

Fish living within tentacles

of a Portuguese man of war

Remora living attached

to other larger fish…

For each of these cases, try to consider what the advantages (or disadvantages)

may be for each symbiotic partner…

symbiosis of animals and bacteria
Symbiosis of Animals and Bacteria

In many animal-bacterial symbioses, the bacteria can provide nutrients for their

animal symbiotic partners… this is perhaps most evident in case of chemoautotrophic

bacteria living in symbioses with vestimentiferan tube worms found around hydro-

thermal vents in the deep oceans…

This symbiotic relationship

is the basis for many of these

deep ocean communities.

Other organisms rely either

directly or indirectly on the

nutrients assimilated into the

system through the symbiotic


symbiosis of animals and bacteria another example
Symbiosis of Animals and Bacteriaanother example…

The squid Eupryman scolopes is symbiotic with the bioluminescent bacteria

Vibrio fischeri.

The squid provides the bacteria an ideal growth environment, and in return it uses

the light generated by the bacteria (controlling light levels) to establish a form of

“counter lighting”. How do you think this may be advantageous to the squid?

These squids are not the only organisms symbiotic with bioluminescent bacteria.

This type of symbiosis is common in a number of fish species…

symbiosis try this one
Symbiosis – try this one…

This is a female angler fish (Linophyryne argyresca) with a male attached to it…

What is going on? Is this symbiosis? If so, what kind???

symbiosis parasitism
Symbiosis - Parasitism

We have not discussed details of parasitic symbiosis, but parasitism is very widespread

throughout marine systems…

A close study of many invertebrates and almost all ocean fish will reveal both external

as well as internal parasites…

Typically parasites include (but are not limited to) various nematodes, annelids (leaches),

and parasitic isopods.