ZO 315 -- COMPARATIVE ANATOMY

EXAM 3

1.	RELATIONSHIPS:  Describe the relationships between 7 of the following 8 pairs of 
terms below.  Do not simply define the terms, but tell me how they are related to 
each other.  You may discuss the 8th pair of terms for extra credit, but be sure to 
indicate which pair of terms is to be graded as the bonus.  [4 pts. each]

	a) pronephric duct // mesonephric duct:
	b) ureteric diverticulum // metanephric blastema:
	c) medulla oblongata // diencephalon:
	d) nephrostome // ostium tubae:
	e) encephalization quotient // intelligence:
	f) opisthonephros // mesonephros:
	g) mesonephric duct // accessory urinary duct:
	h) uterus // oviducts:

2.	Compare and contract the mesonephric and metanephric kidneys.  Give three (3) 
similarities and three (3) differences.  [12 pts.]

3.	Explain sexual bipotentiality.  How are the indifferent gonads alike, and how do they 
ultimately become different?  [15 pts.]

4.	What functions were associated with the three regions of the primitive vertebrate 
brain?  Since these primitive vertebrates had such a simple brain, how did they 
control or coordinate locomotor movements?  [10 pts.]

5.	Why do sharks have relatively large brains?  Why are their brains larger than we 
would expect?  [10 pts.] 

6.	Why is the separation of excretory and reproductive structures more important for 
females than for males?  How is this separation thought to have taken place?  What 
evidence is available?  [10 pts.]

7.	FUNCTIONAL SIGNIFICANCE:	Briefly explain the functional significance of five (5) of 
the following anatomical features.  You may answer the other two for bonus credit, 
but you must mark them EC to receive the extra credit.  [3 pts. each]

	a) scrotal sacs of mammals:
	b) nephrostome:
	c) auricles of cerebellum (aquatic verts):
	d) hypothalamus:
	e) choroid plexus:
	f)  longer nephric tubules of mammals:
	g)  hemipenes:

8.	Describe three anatomical features of mammals and explain how each feature is 
necessary or important for homeothermy (maintenance of warm body temperature).  You 
may include features of any organ system.  [9 pts.]