Flashcards in chapter 37 section 1 Deck (17)
One advantage of a coelom over a pseudocoelom is that a coelom
allows body wall muscles to contract without hindering digestion
One feature that is shared by many mollusks and annelids is the
. Mollusks in the class Gastropoda
have an open circulatory system
Bivalves have the following structures
An octopus generally moves by
crawling along the bottom with its tentacles
Identify the two main regions of a typical mollusk’s body
. The two main regions are the head-foot and the
Which region contains most of the internal organs?
The visceral mass contains most of
the internal organs.
Which region is directly involved with locomotion?
The head-foot is directly
involved with locomotion
. What is the usual function of the mantle in a snail or clam?
The mantle secretes the protective shell.
Contrast the feeding methods of gastropods and bivalves.
Gastropods use their radula to cut through leaves,
scrape up algae, drill holes through the shells of
other mollusks, and harpoon prey; bivalves filter
small organisms from the water that passes
through their gills.
Contrast sexual reproduction of marine clams and most freshwater clams.
Marine clams shed sperm and eggs into the water,
and fertilization occurs externally. In most freshwater
clams, eggs are fertilized internally by
sperm that enter through the incurrent siphon
A cephalopod called the paper nautilus makes a type of shell with its foot.
This shell, which consists largely of protein, is formed only by the female and is used to protect
the eggs. List four reasons why this shell is not a typical molluskan shell
A typical molluskan shell is secreted by the mantle,
consists of calcium carbonate, is formed by both
males and females, and protects the entire animal.
in gastropods, the visceral mass twists 180 degrees in relation to the gastropods head
the fluid in a open circulatory system.
a set of hemolymph filled spaces in the tissues of an animal with an open circulatory system
have their shells divided into two halves and connected by a hinge