Marine invert lecture exam 1- taxa

** Minus foraminifera and radiolaria, which are in the general info deck

True or False: Though protozoans are single-celled, they are still animals

False, they aren’t really animals

What phyla are these?

Foraminifera, as are these.

What phylum and class are these organisms in?

Phylum Radiolaria, class Polycystinea

What phylum and subclass are these organisms in? Describe their life cycle.

Phylum Apicomplexa, subclass Gregarinasina

• Parasitic and large (0.5-2 mm)

• Life cycle:

  • Feeding stage: trophozoite = main stage, haploid, in gut

  • Gametocyst stage: oocysts form inside old trophozoite, ONLY diploid stage

  • Sporozoite: haploid

  • Parasitic stage (invert hosts)

What phylum are these organisms in?

Phylum ciliophora

Approximately how many species are in Phylum Ctenophora?

~200

Describe Ctenophore body tissues:

• Partly mesoglea (gelatinous substance made of proteins, carbs, etc.)

• Have muscles that contract

• Biradial/rotational symmetry

• 8 ctens/comb rows (plates of cilia glued together)

True or False: Ctenophores are mostly benthic, with one order that is planktonic.

False. The opposite is true.

Describe the ctenophore digestive system:

The ctenophore digestive system contains:

• Mouth cavity

• Pharynx

• Stomach

• Anal pores

• For some: tentacles with colloblasts (sticky cells) to keep food down

Describe the ctenophore circulatory system:

Ctenophores don’t have a circulatory system

Describe the Ctenophore excretory and respiratory systems

They dispose of lipid waste through diffusion, and also respire through diffusion.

How do ctenophores reproduce?

They are monoecious (hermaphroditic) and make cydippid larvae.

Describe the ctenophore nervous system.

Ctenophores have nerve nets and a statocyst for balance and orientation.

True or False: Ctenophores use bioluminescence as self-defense.

True, they have a defensive flash.

True or False: genetic evidence suggests that Porifera were the first multicellular organisms, not Ctenophora.

False. Ctenophores are most likely the first multicellular organism.

Describe order Cydippida within phylum Ctenophora.

• Body shape is round with tentacles longer than body

• Tentacles retract into sheaths when not hunting to avoid breakage

• Planktonic

• Larva looks like adult

What phylum and order is this organism in?

Phylum Ctenophora and Order Lobata.

• Tentacles are short, lack a well-developed sheath

• Planktonic

What Phylum and Order is this organism?

Phylum Ctenophora and order Cestida

• very short tentacles, some have small sheaths

• move with body undulations

• Planktonic

What phylum and order is this animal?

Phylum Ctenophora, Order Platyctenida

• Several body shapes in this group

• Short tentacles, small sheath

• PRIMARILY BENTHIC

What order of ctenophores have no tentacles and are carnivorous to other ctenophores?

Order Beroida

• Planktonic

• Flat when swimming, mouth open when hunting.

What are the three main proiferan body types?

• Ascon

• Sycon

• Leucon (big sponges)

What habitat do poriferans inhabit?

Benthic, usually hard substrate

• A few in mud

What is the poriferan digestion system?

They are micro filter feeders and use choanocyte feeding cells

What are the poriferan circulatory, excretory, and respiratory systems?

• Circulatory: none

• Excretory: diffusion

• Respiratory: diffusion

How do poriferans reproduce?

They are monoecious/hermaphroditic and make larvae.

Larvae types (in class): Amphiblastula and Parenchymella

What is the ecology of poriferans?

• eaten by some fish and turtles

• biggest role is on the reefs: they can build or destroy reefs

  • boring sponges destroy

• Larger sponges are homes for inverts

How does poriferan regeneration work?

• Cells of the same species can recognize each other after being broken apart and come back together

Describe class calcarea (phylum porifera)

• Spicules = CaCO3

• Spicules either 1, 3 or 4 rays

• No spongin

• Ascon, sycon, leucon

Describe class hexactinellida (phylum porifera)

• “glass sponges” made of silica

• 6 rayed spicules

• Mud anchor= fibers at bottom

• Spongin absent

• Body: sycon-leucon mix, NO PINACODERM

• Deep water reef and mud habitats

Describe class homoscleromorpha (phylum porifera)

• Spicules=silica

• 4 rays, no axial filament

• Spongin absent

• Body: leucon

• Ecology: encrusting

Describe class Demospongiae (phylum porifera)

• Spicules = silica

• Less than 6 rays, WITH axial

  • some microscleres or megasclerer, some no spicules

• Some have spongin

• Body: leucon

• Some carnivores: spicules snag zooplankton

Sclerosponges have a CaCO3 cover over silica spicules. What phylum and class are they in?

Phylum porifera, class demospongiae

What is the acid test for sponges?

The acid test is used to determine spicule composition. When put in acid, CaCO3 spicules dissolve, but silica don’t

How are sponge pumping rates measured?

By putting dye right by the sponge and watching it be pumped out of the sponge

What type of larvae is this?

Parenchymella

What kind of larvae is this?

Amphiblastula

True or false: Ciliophores are primarily freshwater.

True, most of them live in freshwater, and they have two types of nuclei

Some ciliophorans have a lorica. What is a lorica?

A lorica is a hard covering, similar to a shell.

Describe the habitat, feeding, and ecology of ciliophores.

• Habitat: Planktonic, benthic, and parasitic

• Feeding: Micro omnivores

• Ecology: lower part of food web

Describe Phylum Choanoflagellata

• Body: Single cell, colony

• Flagellum, lorica

• Habitat: planktonic and benthic

• Lead to metozoan