Herbert

Question 0

Four traits that distinguish mammals from reptiles?

Answer 0

Homeothermic
Suckling of young
Body hair
Muscular diaphragm

Question 1

What is the difference between prototheria, metatheria, and eutheria?

Answer 1

Prototheria- egg layers (monotremes)
Metatheria- embryonic young (marsupials)
Eutheria- birth more developed young

Question 2

What are the origins of marsupials and monotremes?

Answer 2

Breaking off from Antarctica 35-40 million years ago

Question 3

What are the origins of Australian eutherians?

Answer 3

Island hopping 5-6 million years ago

Question 4

What are the most easily recognisable differences between ameridelphia and australidelphia?

Answer 4

Structure of the tarsal bones

Also blood proteins, DNA and sperm morphology

Question 5

What are the four orders of marsupials?

Answer 5

Dasyuromorphia
Peramelemorphia
Diprotodontia
Notoryctemorphia

Question 6

What is the name of the opposable 1st digit on the hind foot present in some marsupials?

Answer 6

Hallux

Question 7

Define polyprotodont

Answer 7

Multiple pairs of lower incisors

Question 8

Define diprotodontia

Answer 8

One pair of incisors in the lower jaw.

Question 9

Define syndactyly

Answer 9

Normal occurrence of having two or more fused digits in a mammal species.

Question 10

Between what two digits is syndactyly most common?

Answer 10

II and III

Question 11

What is the dentition of dasyuromorphids?

Answer 11

Polyprotodont

Question 12

Would a spotted quoll have one or more digits fused together naturally?

Answer 12

No, it is a dasyurid, they do not have any syndactyly

Question 13

Bandicoots have three pairs of equal sized lower incisors.

Answer 13

Yes they are of the order peramelemorphia which are polyprotodonts

Question 14

Syndactyly is a defining aspect of peramelemorphia

True/ False

Answer 14

True

Question 15

What does the order notoryctemorphia include?

Answer 15

Marsupial moles

Question 16

All diprotodonts have one pair of lower incisors

True or false?

Answer 16

True

Question 17

What order do koalas belong to?

Answer 17

Diprotodontia

Question 18

All diprotodonts have syndactyly

True/ False

Answer 18

True

Question 19

What is the significance of the path of the ureters in marsupials?

Answer 19

Prevents the fusion of the vagina into a single structure

Question 20

Define polyoesteus

Answer 20

Multiple cycles in breeding season

Question 21

How is ovarian activity modulated in marsupials?

Answer 21

By lactation

Question 22

Describe the placenta of bandicoots koalas and wombats

Answer 22

Chorioallantoic

Question 23

Structure and function of the pouch?

Answer 23

Structure
Invagination of skin of ventral abdomen through a gap in cutaneous muscles, interior skin is hairless, coated by a brown secretion

Function
High humidity and stable temperature for growing young
Mammary glands with long nipples to suckle young

Question 24

What is embryonic diapause?

Answer 24

A female mates while a young is in her pouch. The conceptus is suspended until the first young has finished suckling.

Question 25

How does embryonic diapause work?

Answer 25

Corpus luteum develops and is then inhibited by suckling stimulus

Question 26

Solitary marsupials are usually...

Answer 26

Small nocturnal carnivores/omnivores Exceptions include brushtails and koalas

Question 27

What is sexual size dimorphism?

Answer 27

Significant difference in size between the sexes within a species

Question 28

How do marsupials cope with cold conditions?

Answer 28

1 increase metabolic rate 2 huddling in groups 3 torpor (pseudo hibernation)

Question 29

How do marsupials cope with heat?

Answer 29

Panting, sweating, licking paws

Question 30

How is a marsupial heart different to a eutherians heart?

Answer 30

``` 30% heavier Resting heart rate = lower Max heart rate = similar Max stroke volume is larger CO = greater Resting respiratory rate = lower Tidal volume = greater ```

Question 31

What is the difference in resting body temperature between marsupials and eutherians?

Answer 31

2-3 degrees lower

Question 32

What is a volplane?

Answer 32

Fold of skin between elbow/digit 1 forelimb and stifle/digit 5 of hindlimb that allows for gliding

Question 33

Regarding the hind limb of marsupials what could be regarded as insufficiently developed?

Answer 33

Patella

Question 34

What is the top speed of a kangaroo?

Answer 34

70 km/he

Question 35

Outline the gastrointestinal tract of a carnivorous marsupial.

Answer 35

Very simple No caecum Small intestine and large intestine short with similar diameter.

Question 36

What is the difference between the gastrointestinal tracts of omnivores and carnivores?

Answer 36

``` Salivary glands are larger Small intestine is longer Large intestine more developed for fermentation Caecum = generally large Colon = longer and greater diameter ```

Question 37

What is the dentition of an omnivorous marsupial?

Answer 37

Polyprotodont

Question 38

What is the diastema?

Answer 38

Space where the premolars are present in the mouth of diprotodonts

Question 39

Outline the characteristics of a foregut fermenters gastrointestinal tract.

Answer 39

``` Stomach expanded and sacculated Caudal "hindstomach" = glandular Cranial forestomach = fermentation Small intestine = long Colon and caecum well developed ```

Question 40

What species are foregut fermenters

Answer 40

Kangaroos and wallabies

Question 41

Outline the characteristics of a Hindgut fermenters gastrointestinal tract

Answer 41

Simple stomach | Enlarged caecum and/or colon

Question 42

What is the cardio gastric gland patch?

Answer 42

Invaginated area of mucosa near the cardia

Question 43

What are some problems for Hindgut fermenters?

Answer 43

Less opportunity to absorb microbial amino acids and b vitamins Issues with antibiotics

Question 44

What is caecotrophy?

Answer 44

Ingestion of caecal faeces for nutritional purposes.