BIO3 - Molluscs and Annelids

What is a defining characteristic of annelids?

• Exoskeleton

• Fused rings in their bodies

• Segmented appendages

• External gills

Which of the following are living shelled cephalopods?

• Ammonites

• Nautiluses

• Squids

• Octopuses

1. Which class of molluscs have bodies that are encased in eight dorsal plates?

• Cephalopods

• Gastropods

• Chitons

• Bivalves

According to molecular analyses, how many major clades can annelids be divided into?

• One

• Two

• Three

• Four

Which among the following is an excretory organ present in molluscs remove metabolic wastes from the hemolymph?

• foot

• metanephridium

• radula

• visceral mass

What structures do many members of the Errantia clade possess on each body segment?

• Antennae

• Parapodia

• Tentacles

• Suckers

Which of the following is not a characteristic of a bivalve?

• It has a shell divided into two halves drawn together by sartorius muscles.

• It has sensory tentacles along the edge of its' mantle.

• It is aquatic.

• It has no distinct head.

Which subgroup of annelids includes species that are less mobile and may live in protective tubes?

• Oligochaetes

• Errantians

• Sedentarians

• Leeches

What chemical do leeches secrete to prevent blood from coagulating during feeding?

• Chitin

• Hemoglobin

• Hirudin

• Melanin

Which external feature of a squid does it use to point and direct itself in different directions?

• flagella

• ammonite

• radula

• siphon