Lab 15 Outline: Mammalia

Question 1

Mammalia

Answer 1

• specialized sweat glands
• body covered with hair
• dentary is the only bone in the lower jaw; articulates with squamosal bone
• heterodonts
• endothermic
• 4 chambered heart and a pair of lungs
• internal fertilization; viviparious

Question 2

specialized sweat glands of mammals

Answer 2

• mammary glands
• sweat glands
• sebaceous glands
• scent glands

Question 3

body covered with hair

Answer 3

-vibrissae: sensory
guard hairs:
under fur: insulation

Question 4

Prototheria (Monotremata)

Answer 4

• platypus and echidnas
• only five extant species
• offsprings are supplied with milk, but mother has no nipples
• two uteri joined at urogenital passage that opens in the cloaca
• most ancestral lineage of mammals

Question 5

Metatheria (Marsupialia)

Answer 5

• most with marsupium
• short gestation period: newborn is poorly developed (altricial)
• two seperate uteri and vaginas; males often with bifurcated(branching) penis

Question 6

Eutheria ( “True” Placentals)

Answer 6

most diverse group of mammals
fully viviparous mammals with placenta
offspring are born more developed (precocial)