Exam I

Question 1

Taxonomy of Mammals

Answer 1

Domain: Eukarya
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Mammalia
Subclass: Prototheria
Subclass: Theria
Infraclass: Metatheria
Infraclass: Eutheria

Question 2

What does “proto” mean?

Answer 2

Before

Question 3

What does “theria” mean?

Answer 3

Placenta

Question 4

What does “meta” mean?

Answer 4

Middle

Question 5

What does “eu” mean?

Answer 5

True

Question 6

What types of mammals belong to the subclass prototheria?

Answer 6

Egg laying mammals

Question 7

What types of mammals belong to the subclass theria?

Answer 7

Mammals with some type of placenta

Question 8

What type of mammals belong to the infraclass metatheria?

Answer 8

Marsupials; mammals with very little placenta development—not all have a pouch.

Question 9

What type of mammals belong to the infraclass eutheria?

Answer 9

Mammals with extensive growth of placenta and lengthy pregnancy.

Question 10

What are the unique characteristics of mammals?

Answer 10

1. Hair
2. Skin
3. Sweat Glands
4. Sebaceous Glands
5. Sweat Glands
6. Heterodont dentition
7. Muscular Diaphragm
8. Single innominate Bone
9. Synapsid Skull

Question 11

Describe the mammals hair?

Answer 11

Grows out of the hair follicle.
Most likely evolved as insulator for nocturnal mammals.
Some mammals are hairless as adults (dolphins).
Made of a protein karotin

Question 12

What are sweat glands?

Answer 12

Cool the body using evaporative cooling.

Humans and horses have the most; most mammals have many fewer; some have none.

Question 13

What are scent glands?

Answer 13

They can be located in many different places including the eyes, anal region, and between the toes.

Question 14

What are sebaceous glands?

Answer 14

They are associated with almost all hair follicles and they secrete oils to protect the hair.

Question 15

What is heterodont dentition?

Answer 15

Mammals who have different types of teeth.

Incisors, canines, pre-molars, and molars.

Question 16

Evolution of teeth?

Answer 16

Some have secondarily evolved to have no teeth or homodont dentition; some have lost certain types of teeth (i.e. rodents have no canines).

Question 17

How can you determine a mammals diet?

Answer 17

The numbers and shapes of teeth in mammals reflect their diet.

Question 18

What is the muscular diaphragm?

Answer 18

It is the membrane between the abdominal and thoracic cavities. It allows the mammal to actively draw air into the lungs.

Question 19

What is the single innominate bone?

Answer 19

It is the bone in the pelvis that articulates with the bones of the leg and spine. It increases core strength. It is located above the legs rather than side to side of the mammal’s body.

Question 20

How does the innominate bone change the movement patterns of mammals?

Answer 20

It causes mammals to undulate up and down while fish, reptiles undulate side to side.

Question 21

What is the synapsid skull?

Answer 21

Mammals and the reptile group with which they share a common ancestry, the synapsida, have a skull with one temporal opening by the squamosal bone.

Question 22

What is deciduous dentition?

Answer 22

Includes incisors, canines, and premolars, “milk teeth” and are replaced by permanent dentition.

Question 23

Why are deciduous dentition replaced by permanent dentition?

Answer 23

As young mammals their diets are different/change as they develop into adults. They have precise inclusion.

Question 24

Evolution of teeth?

Answer 24

Ancestral-cusps in a line

Question 25

Tribubercular Pattern?

Answer 25

3 cusps in triangle in upper molars

Question 26

Mastication?

Answer 26

Complex chewing movements. Used to initially crush and puncture food, and later sliced by shearing surfaces of molars.

Question 27

Teeth patterns of carnivores?

Answer 27

Cheek teeth evolve as blade-like (carnassial). They are adapted for slicing flesh and have a jaw action that is scissor-like

Question 28

Teeth patterns of herbivores?

Answer 28

Cheek teeth evolve as quadrate with flattened occlusal surfaces and the jaw action is horizontal and transverse.

Question 29

What is the dental formula for mammals?

Answer 29

It specifies the number and position of teeth on one side. Incisors 3/3, canines 1/1, premolars 4/4, molars 2/3 or (3/3, 1/1, 4/4, 2/3) x 2= 42

Question 30

How are individual teeth distinguished?

Answer 30

Individual teeth designated with upper case letters for upper teeth and lower case letters for lower teeth. P3 is upper premolar 3 m2 is lower molar 2

Question 31

How do you calculate the number of teeth in mammals?

Answer 31

(3/1 + 1/0 + 1/1 + 4/4) x2 =30 teeth

Question 32

Describe the tooth structure?

Answer 32

Cementum binds the tooth to the jaw (annually laid down) Inner dentine Outer enamel

Question 33

Brachydont?

Answer 33

short-crowned teeth

Question 34

Hypsodont?

Answer 34

high-crowned teeth

Question 35

Ever-growing?

Answer 35

continuously growing

Question 36

Diastema?

Answer 36

Space between incisors/canines and cheek teeth

Question 37

Bundont?

Answer 37

Rounded cusps on molars; covered in enamel

Question 38

Lophodont?

Answer 38

Cusps form ridges; not covered in enamel; hypsodont

Question 39

Selenodont?

Answer 39

Cusps form crescents; not covered in enamel; hypsodont

Question 40

The skull of mammals?

Answer 40

``` Single craniomandibular jaw joint Dentary/squamosal articulation Brain case is large Sagittal and lambdoidal crest Zygomatic arch usually present Secondary palate present Three middle ear bones Tympanic Auditory bulla ```

Question 41

What is the sagittal and lambdoidal crest?

Answer 41

Jaw muscle attachment

Question 42

What is the zygomatic arch?

Answer 42

Jaw muscle attachment

Question 43

What is the purpose of the secondary palate?

Answer 43

It increases air intake.

Question 44

What is the purpose of the three middle ear bones?

Answer 44

Transmit sound to the cochlea for better hearing.

Question 45

Which bones articulate with the skull?

Answer 45

Dentary/squamosal articulation

Question 46

What does articulation mean?

Answer 46

Place where bones come together usually in an area where the bones move relative to each other.

Question 47

How many bones does the pelvis consist of?

Answer 47

One. It has 3 processes: ilium, ischium, and pubis.