The organ of nutrition used in fetal development in the most successful mammals is the

A) mammary gland.
B) egg.
C) pouch.
D) placenta.
E) amniote egg.

Which characteristics best describe earthworms?

A) polychaete; fluid filled coelom
B) oligochaete; open circulatory system
C) moves by longitudinal muscle contraction; hydrostatic skeleton
D) oligochaete; scavengers; closed circulatory system
E) hermaphrodites that fertilize themselves; open circulatory system

The National Labor Union was one large union that directly represented workers from many trades, crafts, and industries.

During periods of fasting, why is fat said to have a protein-sparing effect?

A) The body oxidizes its spare protein before it depletes its fat reserves.
B) The body metabolizes fats and proteins through the same metabolic pathways.
C) The body must have an adequate fat intake in order to absorb and metabolize proteins.
D) The body must have an adequate protein intake in order to absorb and metabolize fats.
E) The body does not oxidize its proteins unless it has consumed its fat reserves first.

Wings on insects, flowers on plants, and feathers on birds are all examples of variations of some preexisting structures, otherwise known as:

A) preadaptations.
B) allopolyploidy.
C) paedomorphosis.
D) allometric growth.
E) punctuated equilibrium.

Continuous capillaries

A) have many thin areas called fenestrae.
B) are freely permeable to large molecules such as hormones.
C) have a wall where the endothelial cells fit very tightly together.
D) are more permeable than fenestrated capillaries but not as permeable as sinusoidal capillaries.
E) are characterized by continuous pores.