The internal skeleton of echinoderms is made of calcium-stiffened ____ that develop from mesoderm

a. ampullae
b. ossicles
c. radial canals
d. ring canals
e. madreporites


B

Biology & Microbiology

You might also like to view...

The H5N1 influenza killed more than 50% of those infected

a. True b. False Indicate whether the statement is true or false

Biology & Microbiology

Animal breeders use a _______ to determine whether an organism is heterozygous or homozygous for a particular trait.

a. Punnett square b. reciprocal cross c. test cross d. self cross

Biology & Microbiology

In flowering plants, pollen grains form in the

flower's male parts called

a. stamens. b. anthers. c. carpels. d. megaspores. e. endosperms

Biology & Microbiology

In DNA, the phosphate groups and the sugars are the outside of the double helix

a. true b. false

Biology & Microbiology