Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Vertebrate Zoology > Amphibians > Flashcards

Amphibians Flashcards

1
Q

Describe the class amphibia

A
  • aquatic / terrestrial
  • 3 extant orders within subclass Lissamphibia, shared derived characters in skin, eyes, ears, teeth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 3 extant orders in the subclass Lissamphibia?

A
  • anura - frogs and toads
  • caudata - salamanders and newts
  • gymnophiona - caecilians
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe aquatic larvae

A
  • biphasic life history with metamorphosis
  • obligatorily aquatic larvae - facultatively terrestrial adults
  • lateral lines
  • gills
  • fish-like circulatory systems
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe gills in aquatic larvae

A
  • external in embyonic stage
  • internal until metamorphosis in anurans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a classic Paleozoic amphibian example?

A
  • Archegosaurus
  • Larva 15cm, adult 1.5m
  • series showing less external gills over growth, increased skeletal growth
  • bony dermal scales unlike Lissamphibians
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the possible evolutionary origins of modern Lissamphibians?

A
  • Temnospondyls: carboniferous - early cretaceous
  • Lepospondyls: carboniferous - early permian
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the paedomorphism hypothesis of anuran origins?

A
  • retention of larval characters in an adult organism
  • juvenile characters of anurans:
  • miniature in size
  • preorbital skull short with broad rounded snout
  • relatively large orbits
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the derived character of subclass Lissamphibia?

A
  • Greek lissamphibia - smooth skin
  • members of all 3 orders have skin that lacks scales, kept moist by mucus glands, permeable and contains poison glands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe cutaneous gas exchange in amphibians

A
  • can obtain 20-95% oxygen through skin
  • 2/3 CO2 excretion through skin
  • continiously in both air and water
  • some needed in water
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are examples of amphibians that are needed in water for gas exchange?

A
  • many ranid frogs semi-aquatic
  • pipidae entirely aquatic
  • northern temperate frogs hibernate in water using cutaneous gas exchange
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe amphibian skin

A
  • outer epidermis and inner dermis
  • epidermis lightly keratinized and multi-layered
  • glands present
  • chromatophores in dermis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the lightly keratinized and multi-layered epidermis

A
  • thin outer layer of dead cells, little water resistance, periodic moults
  • layer of keratinocytes, limiting barrier for solute and water transport
  • lower layer regenerates epidermis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is an example of amphibian epidermal disease?

A

Chytridiomycosis:
- chytrid fungus
- skin parasite - superficial keratin layers:
- increased sloughing, decreased osmotic regulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What glands are present in the amphibian dermis?

A
  • mucus
  • poison
  • bioactive secretions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe mucus glands in amphibians

A
  • slippery and slimy mucus
  • contains mucopolysaccharides and mucoproteoglycans
  • moist surface to increase gas exchange & decrease water loss and friction
  • increased body temp leads to mucus discharge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe poison glands in amphibians

A
  • granular
  • secrete bioactive compounds, some from arthropod prey
  • e.g., alkaloids, bioactive peptides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the functions of bioactive secretions?

A
  • anti-microorganism
  • anti-oxidation
  • anti-predation
  • neuroendocrine regulation
  • imunoregulation
  • mating
  • anti-parasitism
  • wound healing
  • analgesia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the different chromatophores present in amphibian dermis

A
  • dermal chromatophore unit: triple cell structure
  • zanthophore - yellow
  • erythrophore - red
  • iridophore - blue or white
  • melanophore - black/brown
19
Q

Describe how iridophores give blue or white colours

A

reflective platelets (purine crystals) scatter light

20
Q

Describe how rapid colour changes occur in amphibian dermis

A
  • when frog darkens: melanosomes migrate around iridophore
  • hormonal controls
  • dimensions of iridophore platelets can change
21
Q

Describe chromatophore mutants with transparent skin

A
  • mutation to lose melanophores and iridophores
  • melanophore only loss is red
  • iridophore only loss is brown/black
  • double mutant has transparent skin
  • white peritonea on some organs, gall bladder transparent yellow and ova green
22
Q

Why are poison frogs variable colours?

A

bright colours advertise toxicity to predators - aposematism

23
Q

Describe the evolution of Early Triassic vs Modern Anuran skeletons

A

Early Triassic -> Modern Anuran
Short ilium -> Elongated ilium
No urostyle -> Urostyle
14 presacral vertebrae -> 5-9 presacral vertebrae
No tough sacral region -> Toughened sacral region
Shorter hindlimbs -> Longer hindlimb
Short tarsals -> Elongated tarsals
Tibia and fibula separate -> Fused tibia and fibula
Radius and ulna separate -> Fused radius and ulna

24
Q

What do the adaptations of modern anuran allow for?

A

better jumping

25
Q

Describe the evolution of anuran pelvic and thigh muscles

A
  • tail muscle of caudate - anuran urostyle muscle for dorsal rotation
  • semimembranosus pelvis to knee in both
  • strong muscle for initial phase of jumping, swimming, walking
26
Q

What is the difference between Anurans and Caudates?

A

caudate - vertebrate with a tail
anuran - no tail

27
Q

Describe the anuran pectoral girdle

A
  • complex and flexible girdle absorbs impact on landing
  • derived elements highlighted
  • structural variations used in frog taxonomy
28
Q

Describe the locomotion of landing in American bullfrogs

A

steep and fast takeoff
land first on extended forelimbs -> belly -> feet:
- belly hit, legs flexing
- legs mostly flexed and feet slap
- legs/feet elevated and hips flexed
- feet put down, toes held up
- toes put down

29
Q

Describe the evolution of basal frog ‘belly flop’ landing

A

rocky mountain tailed frog - slow and flat take-off
land on belly - same limb positions as takeoff
- body hits, limbs extended back
- movement stopped, hands going forward
- hands down, legs protracting over body
- legs/feet elevated, hips flexed
- feet put down, toes held up
- toes put down

30
Q

Describe the body characteristics of aquatic frogs

A
  • swim using powerful hindlimbs
  • lack tongues and teeth
  • suction feeding
  • forelimbs manipulate prey
  • clawed hindlimbs tear prey apart
  • retain lateral line as adults
31
Q

Describe the anuran body characteristics of tree frogs

A
  • several families - convergent evolution
  • tiny with long limbs
  • many change colour for camoflage
  • forward facing eyes
  • adhesive pads on digits
32
Q

Describe the highly derived anuran cranium

A
  • several typical tetrapod elements lost or fused
  • most of skull roof - frontoparietal complex
  • palate highly fenestrated
  • lacks dentition
  • frontoparietal - fusion of 2 bones at top
  • wide orbits for sunlight
33
Q

Describe amphibian eye bulging muscles

A
  • retractor bulbi retracts eyeball into buccal cavity - pushes food into oesophagus
  • levator bulbi eyeball after swallowing
  • use fenestration in cranium
34
Q

Describe anuran vision

A
  • large and protuberant - 360 degrees of vision
  • binocular vision of over 100 degrees to front
  • prey detected by movement and contrast
35
Q

Describe lingual feeding in anurans

A
  • protrudable tongue attached at lower jaw front
  • pivots around muscle - flipped out
  • prey adheres to sticky mucus
  • aquatic frogs lack tongue - use suction
36
Q

Describe the organs present in the body cavity

A
  • liver - dark lobes
  • stomach and intestine tubular
  • fat bodies - yellow filamentous structures
  • urinary bladder - large structure at posterior
  • lungs ‘underneath’ pectoral bones
37
Q

Describe water homeostasis in anurans

A
  • in dehydrated frog hypothalamus - increased AVT
  • antidiuretic peptide hormone leads to increase aquaporin water channels in kidney, urinary bladder, pelvic skin
  • frogs sense and do not sit in hyperosmotic water
38
Q

Describe the lung structure in frogs

A

gas exchange at alveoli between raidal folds that project into lumen
simple structure

39
Q

Describe buccal pump breathing and ventilation

A
  • narrow vocal slits on each side of buccal cavity - elastic vocal sac chamber
  • inspiration: buccal cavity expands, air drawn into cavity
  • expiration: buccal cavity contracts, air forced out
40
Q

Describe the 3 chambered heart in diving/hibernating frogs

A
  • right atrium: oxygen rich blood from cutaneous respiration
  • longitudinal baffle in outflow tract - decreased mixing of 2 flows
  • single ventricle pumps flood from both atria
  • if underwater: vascular constriction of pulmonary circuit - flow down left atrium
  • if lungs in use: pulmonary circuit - increased flow via left atrium
41
Q

Describe the female organs in amphibians

A
  • ovaries beside kidneys
  • bulge with ova if gravid
  • ova pass down pair of ovidcuts to cloaca
42
Q

Describe male organs in amphibians

A
  • testes attached to ventral surface of each kidney
43
Q

Describe fertilization in amphibians

A
  • external fertilization: cloacal apposition in most anurans
  • amplexus - male on back of female
  • male forelimbs wrapped round her body - stimulates female to release ova as spawn
  • sperm ejaculated from male cloaca onto eggs as female lays them

Vertebrate Zoology (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions