Mammalian Characteristics

Question 1

What is a Mammal?

Answer 1

1. fur, hair, pelage
2. mammary glands
3. muscular diaphragm
4. jaw composed of single bone (dentary)
5. three bones in the middle ear

Question 2

What are the 3 bones in the middle ear?

Answer 2

1. stapes
2. quadrate (incus)
3. articular (malleus)

Question 3

What are the parts of a hair?

Answer 3

(starting from the inner hair)

1. medulla
2. cortex
3. cuticle scale

Question 4

What makes hair colored?

Answer 4

Results from melanin granules

1. pheomelanin (yellows and reds)
2. eumelanin (black and brown)

Question 5

What are the different types of coloration?

Answer 5

1. countershading
2. disruptive
3. warning
4. cryptic

Question 6

Gloger’s Rule

Answer 6

• animals are darker in warm/ humid areas
• animals are lighter in dry areas
• this is b/c melanin and hair are degrading by bacteria, thermoregulation, and crypsis

Question 7

Modifications of Skin (scales)

Answer 7

Epidermal Derived
-beavers, opposum, muskrat
-overlp and not bony
Dermal Derived
-aramdillos
-do not overlap and bony

Question 8

Specialized Hairs

Answer 8

1. vibrissae
   - sensory and tactile hairs
   - whiskers
2. undercoat
   - wool, thermoregulation
3. gaurd hairs
   - protection, markings

Question 9

Axial Skeleton

Answer 9

1. cervical
2. thoracic
3. lumbar
4. sarcum
5. coccyx

Question 10

Teeth

Answer 10

Homodont: all the same
Heterodont: all different
Thecodont:teeth are rooted
Diphydont: 2 sets over life time

Question 11

Secodont

Answer 11

• carnivores
• primative
• sharp cutting teeth

Question 12

Bunodont

Answer 12

• omnivores

- round cusped

Question 13

Lophodont

Answer 13

• elephants, horses

- expanded ridges

Question 14

Selenodont

Answer 14

• crescent shaped ridges

- elk, deer

Question 15

What are the carnassial pairs?

Answer 15

The last upper premolar and the first lower molar

Question 16

What is the Diastema?

Answer 16

The empty space between the incisors and premolars