J.1 Lower Invertebrates MC

Aboral

The surface of an organism opposite to its oral surface.

Reproduction and Feeding

The two life functions that all animals have.

How many of the following are TRUE about animals that have a polymorphic life cycle?

• Larvae help distribute the species

• Larvae can reproduce more adults

Characteristics of adult sessile animals

Adult sessile animals may have features like larvae, broadcasting, being hermaphroditic, or radial symmetry.

Spongin

A protein that provides support in poriferans.

Function of Amoebocytes

produce spicules.

How do hermaphroditic animals like sponges avoid self-fertilization?

developing sperm and ova at different times.

5. Sponges exist at the cellular level of organization. What does this mean? 

lack true tissues.

Nematocyte

A cell type that is NOT characteristic of poriferans.

5. What causes the formation of Gemmules

inclement water conditions.

5. How many of the following distinguish the body cavity of a jellyfish from that of a sponge?

Lined with endoderm

Used for extracellular digestion

: Allows gas exchange with tissues

Sac-shaped instead of tube-shaped

5. How many of the following cells types are sandwiched between the endoderm and the ectoderm of Hydra?

Nerve and muscle cells

Medusa

What do jellyfish polyps produce when they reproduce vegetatively?

Anthozoans

5. Which class of Phylum Cnidaria contains sessile members that help build coral reefs? 

5. Which is TRUE of most jellyfish?

either male or female and reproduce by broadcasting gametes.

Cephalization

5. Aggregation of nervous tissue in one region of an organism, thus defining a “head”?

Polyp

The non-motile (or lesser motile) body form of a cnidarian.

Hermaphrodite

An organism that bears both genders.

Mesoglea

Layer of cells lying between ectoderm and endoderm not differentiated into a tissue.

Schyphozoa

Class of cnidarians to which jellyfish belong.

Phylogenetic tree

A diagrammatic arrangement of phyla showing supposed evolutionary relationships.

Nerve net

Random arrangement of nerve cells lacking main nerve cords and ganglia in cnidarians.

Polymorphic

having more than one body form in their life cycle.

Nematocysts

Cells that use water pressure to release a barbed protein when disturbed.

Spicule

Deposits that form skeletal/supporting structures in sponges.

Nephridiophores

Tiny tubes that collect waste fluids from flame cells and conduct them outside.

Cyst

A sac-like pocket developing around an irritant, such as a dormant worm larva.

Pharynx

Muscular region anterior to the esophagus that passes food to the esophagus.

Pseudocoelom

A body cavity having mesoderm on its outer surface and endoderm on its inner surface.

Ladder-like

Descriptive of the bilateral arrangement of the nervous system of planaria.

Proglottid

Hermaphroditic section of a tapeworm.

Larva

The immature version of an animal that undergoes metamorphosis.

Scolex

Anterior end of a tapeworm specialized for attachment to host tissues.

Filaria

Parasitic thread-like nematode, responsible for conditions like elephantiasis.

Ganglion

Collection of nerve cell bodies outside of the central nervous system.

Body wall tissues of planarian

Correct order from GVC is endoderm – mesoderm – ectoderm.

36. Which features contribute to the swimming motion of planaria?

Cilia and muscle tissue

36. From what feature did flame cells derive their name?

cilia.

Eyespots of a planarian

Light sensitive

 Bilaterally symmetrical

 Connected to ventral nerves

40. After a planarian digests its food, how are the nutrients delivered to cells?

Directly from the extensive GVC

41. What travels along nephridiophores?

They carry fluid wastes.

41. Which of the following correctly matches these flatworms to their lifestyle?

Planaria are free living; flukes and tapeworms are parasitic.

Ascaris

An organism that is NOT a member of Phylum Platyhelminthes.

41. The primary host in a polymorphic life cycle is the host that?

the adult parasite lives in

41. A polymorphic life cycle provides an advantage

to a parasite because the?

young depend on a different food source

46. Which system in a fluke is the MOST developed?

The reproductive

46. How is the scolex of a tapeworm specialized?

attachment to a host.

46. What could one expect to find in a proglottid?

sex organs.

46. How is the body plan of a nematode different from that of a platyhelminth

space between mesoderm and endoderm

46. What feature of the intestines of a nematode distinguishes them from a GVC?

two openings