A student observes a wormlike organism crawling about on dead organic matter. Later, the organism sheds its outer covering. One possibility is that the organism is a larval insect (like a maggot). However, it might be a member of the phylum ________, and one way to distinguish between the two possibilities is by looking for ________.
A) Platyhelminthes; a cuticle of chitin
B) Nematoda; an alimentary canal
C) Annelida; a body cavity
D) Nematoda; a circulatory system
E) Annelida; muscle in the body wall
Water striders serve as a model organism for the study of sexual conflict between males and females.
Model Organism Drosophila
For some Americans, religion is an “easy-going, makes-little-difference” matter, as expressed in ...
The three states of matter: solid, liquid, and gas.
Type of pathogen organism
Chemical, Biochemical, and Organic Sedimentary Rocks