Porifera
Cnidaria
Vocabulary
Career or Challenge
Mixed Review
100

The term for a sponge's lack of a fixed body shape.

What is asymmetry?

100

The type of symmetry seen in jellyfish and coral.

What is radial symmetry?

100

The broadest level of taxonomic classification.

What is Domain?

100

This scientist studies marine animals and ocean ecosystems.

Who is a marine biologist?

100

The stinging structure inside a cnidocyte.

What is a nematocyst?

200

The opening sponges use to expel filtered water.

What is the osculum?

200

The free-swimming body form of a cnidarian.

What is a medusa?

200

This structure lets scientists compare DNA between species.

What is biochemistry (evidence)?

200

Sketch a simple sponge body plan and label 3 structures.

Structures may include ostia, osculum, spongocoel, choanocytes, spicules, amoebocytes, holdfast, porocytes, pinacocytes, ectoderm, endoderm, and/or mesohyl.

200

The single-opening digestive cavity in cnidarians.

What is the gastrovascular cavity?

300

The cells that create water current and trap food in a sponge.

What are choanocytes?

300

The (mostly) sessile, tube-shaped body form of a cnidarian.

What is a polyp?

300

A structure similar due to shared ancestry.

What is a homologous structure?

300

This scientist works most directly with the DNA and protein of organisms.

Who is a molecular biologist?

300

One example of a human threat to coral reefs.

What is warming ocean temperatures due to global warming?

What is pollution?

What is overfishing?

(Answers will vary. Any valid answer is acceptable.)

400

True or False: sponges have true tissues and organs. Explain why or why not.

False. Porifera cells work largely independently, with no organs or nervous system.

400
The simple, decentralized nervous system found in cnidarians.

What is a nerve net?

400

Convergent evolution produces this type of structure.

What is an analogous structure?

400

Sketch a cnidarian body plan, name the body plan, and label 3 structures.

Body plans include polyp or medusa.

Structures may include bell, mesoglea, gonads, tentacles, oral disc, column, basal/pedal disk, mouth, cnidocytes, nematocysts, and/or gastrovascular cavity.

400

Compare Porifera and Cnidaria by naming one key structural difference and one similarity between the two phyla.

Differences may include: What is symmetry? (asymmetry vs radial symmetry), What are specialized cells vs specialized tissues? 

Similarities may include: What is lack of cephalization? (no head or brain), What is aquatic organisms?, What is invertebrates/no backbone?

Any valid answer is acceptable.

500

Explain why a sponge can survive with no brain, muscles, or body systems.

It filter-feeds passively using choanocyte water currents and doesn't need to actively move or hunt to survive. No moving, no decision-making, no need for a brain or muscles. No need for body systems because the specialized cells work independently for all of the sponge's needs.

500

Explain why radial symmetry is well-suited to an animal that doesn't actively hunt.

It allows the animal to sense and respond to food or threats from every direction equally, without needing to "aim" a front end, or having blind spots "behind" the organism.

500

Explain the difference between an observation and an inference, with an example.

Observation = information gained through the five senses

Inference = a conclusion drawn from an observation along with prior knowledge

Example - answers will vary

500

This scientist spends more time in the natural habitats of animals than in a lab or office.

Who is a wildlife biologist?

500

Explain what coral bleaching is and what causes it.

Coral expels the algae, called zooxanthellae, living in its tissue due to some form of stress that causes the algae to produce toxins instead of food (usually increased water temperatures). The zooxanthellae provide the coral its color and 90% of its food, and expelling it causes the coral to lose its color and appear white, as well as lose its food source.