Deck 19: Amphibians: the First Terrestrial Vertebrates

Question 1

Which of the following designations applies to 4-legged "crown group" descendants in the sarcopterygian lineage.Recall that "crown group" refers to 4-legged extant animals and their closest common ancestor.

A)Tetrapoda
B)Gnathostome
C)Apoda
D)Agnatha
E)Amniote

Answer 1

A

Question 2

The sternum is reduced or absent in members of the order

A)Caudata.
B)Urodela.
C)Gymnophiona.
D)Anura.
E)Caudofoveata.

Answer 2

D

Question 3

The ancestral tetrapodomorph lineage which led to reptiles,birds,and mammals is called the ____________ lineage.

A)Actinopterygii
B)Amphibia
C)Lissamphibia
D)Reptiliomorpha
E)Agnathan

Answer 3

D

Question 4

A fossil often depicted as an example of an early amphibian is

A)Latimeria.
B)Hyla.
C)Archaeopteryx.
D)Ichthyostega.
E)Etheostoma.

Question 5

Members of the salamander family Salamandridae are commonly called

A)caecilians.
B)newts.
C)anurans.
D)neotenes.
E)whiptails.

Question 6

The last trunk vertebra of the amphibians is the __________ vertebra.

A)thoracic
B)sacral
C)lumbar
D)cephalic
E)caudal

Question 7

A ventral plate of bone called the __________ is present in the anterior,ventral trunk region of many amphibians.This plate provides support for the forelimbs and protection for internal organs.

A)ilium
B)coccyx
C)sternum
D)ischium
E)scapula

Question 8

Caecilians belong to the amphibian order

A)Caudata.
B)Anura.
C)Urodela.
D)Caudofoveata.
E)Gymnophiona.

Question 9

The skin of amphibians is

A)highly glandular.
B)thick and dry.
C)covered with a fine hair.
D)covered with fine scales.

Question 10

Salamanders belong to the amphibian order

A)Anura.
B)Gymnophiona.
C)Squamata.
D)Testudines.
E)Caudata.

Question 11

The structures responsible for color and color changes in amphibian skin are

A)mucous glands.
B)warts.
C)keratins.
D)pigment glands.
E)chromatophores.

Question 12

The ilium,ischium,and pubis comprise the __________ of amphibians.

A)hind limbs
B)front limbs
C)neck
D)pectoral girdle
E)pelvic girdle

Question 13

Larval stages of frogs and toads are usually referred to as

A)tadpoles.
B)newts.
C)neotenic.
D)amphipods.
E)amniotes.

Question 14

The most fully terrestrial salamanders belong to the family

A)Plethodontidae.
B)Salamandridae.
C)Amphiumidae.
D)Bufonidae.
E)Ranidae.

Question 15

Frogs and toads belong to the amphibian order

A)Tetrapoda.
B)Anura.
C)Urodela.
D)Gymnophiona.
E)Caudofoveata.

Question 16

Fertilization is always internal in caecilians; larval stages are often

A)carried in special pouches on the back of the male until development is completed.
B)neotenic.
C)called newts.
D)held in the oviducts and the young emerge from the female as miniatures of the adult.
E)carried in the mouth of the female until development is completed.

Question 17

True toads belong to the family

A)Hylidae.
B)Dendrobatidae.
C)Rhynchocephalia.
D)Ranidae.
E)Bufonidae

Question 18

Female salamanders have a special pouch,the __________,in which sperm are stored.

A)ovarian cecum
B)vaginal pouch
C)spermatheca
D)spermatophore
E)uterus

Question 19

When the amphibians first moved onto land,there was

A)an environment relatively free from predators.
B)a readily available food source.
C)competition with the reptiles.
D)An environment relatively free from predators and a readily available food source are both correct.

Question 20

Members of the amphibian order Anura have the tail vertebrae fused into a rodlike

A)pygidium.
B)telson.
C)uropod.
D)urostyle.
E)anal cirrus.

Question 21

Gas exchange across the skin is called

A)ram ventilation.
B)countercurrent exchange.
C)cutaneous respiration.
D)buccopharyngeal exchange.
E)branchial respiration.

Question 22

In amphibians,a __________ valve in the conus arteriosus or ventral aorta helps direct blood into pulmonary and systemic circuits.

A)bicuspid
B)tricuspid
C)mitral
D)semilunar
E)spiral

Question 23

Unlike other vertebrates,amphibians have contractile vessels called lymphatic __________ that pump fluids through the lymphatic system.

A)arches
B)hearts
C)aortae
D)arteries
E)capillaries

Question 24

Larval amphibians are usually __________ in their feeding habits.

A)sanguinivorous
B)carnivorous
C)herbivorous
D)omnivorous
E)insectivorous

Question 25

When in water amphibians

A)produce large quantities of ammonia.
B)produce minute quantities of hypertonic urine.
C)excrete large quantities of salt through the kidneys.
D)actively absorb large quantities of water through the skin.
E)produce large quantities of hypotonic urine.

Question 26

The _______ of the amphibian middle ear is the single auditory ossicle.

A)incus
B)malleus
C)tympanum
D)quadrate
E)stapes

Question 27

The __________ receives airborne vibrations and transmits them to the middle ear.

A)protractor lentis
B)operculum
C)columella
D)stapes
E)tympanic membrane

Question 28

Which of the following is a function of the midbrain of amphibians?

A)processing visual sensory information
B)regulation of heartbeat
C)regulation of color exchange
D)regulation of visceral functions
E)initiation of receptor responses

Question 29

__________ act to amplify the calls of frogs that are produced by the vocal cords.

A)Pulmonary diverticulae
B)Vocal sacs
C)Amphibian tongues
D)Spiral valves
E)Vocal valves

Question 30

Much of the movable lower eyelid of amphibians is transparent and is called the

A)optic tectum.
B)nictitating membrane.
C)protractor lentis.
D)retractor lentis.
E)tympanum.

Question 31

__________ is a series of abrupt structural,physiological,and behavioral changes that transform a larval frog into an adult.

A)Regeneration
B)Neoteny
C)Metamorphosis
D)Amplexus
E)Parthenogeny

Question 32

The __________ of the amphibian heart receives blood from the lungs.

A)left atrium
B)left ventricle
C)right atrium
D)sinus venosus
E)pulmonary heart

Question 33

Because amphibians depend on external sources of heat to maintain body temperatures,they are said to be

A)endothermic.
B)amphithermic.
C)homeothermic.
D)isothermic.
E)ectothermic.

Question 34

This type of organism has been implicated in the recent global decline of amphibians.

A)nematode
B)fungus
C)tsetse fly
D)copepod
E)amoeba

Question 35

To focus on near objects,the amphibian lens is moved forward by the __________ muscle.

A)retractor pencil
B)posterior adductor
C)protractor lentis
D)anterior adductor
E)spectator

Question 36

The outermost structure of the ear of anuran amphibians is a/an

A)pinna.
B)semicircular canal.
C)tympanic bulla.
D)tympanic membrane.
E)auditory meatus.

Question 37

In their feeding habits,most adult amphibians are

A)herbivores.
B)carnivores.
C)sanguinivores.
D)frugivores.
E)scavengers.

Question 38

Pulmonary ventilation in amphibians with lungs is accomplished by

A)the diaphragm.
B)the ribs.
C)ram ventilation.
D)a buccal pump.
E)countercurrent exchange.

Question 39

In anurans,fertilization involves the male mounting and clasping the female followed by external fertilization--a behavior called ____________.This behavior is in contrast to the use of __________ in salamander sperm transfer.

A)amplexus/spermatophores
B)clasping/amplexus
C)appositioning/ copulation
D)copulation/ spermatophores
E)copulation/ amplexus

Question 40

In anurans,long hind limbs and powerful muscles form an efficient __________ system for jumping.

A)lever
B)undulatory
C)hydrostatic
D)accordion
E)pulley

Question 41

Amphibians are vulnerable to a wide range of environmental disturbances.Conservation measures,therefore,need to be very wide-ranging and include both short-term and long-term efforts.Based on what you now know of amphibian biology,check all of the following statements that could be reasonable conservation strategies?

A) In the long term,wetland conservation measures will preserve the freshwater habitats that amphibians need for breeding,larval development,and adult survival.
B) In the short term,captive breeding programs and fungal treatment programs can help preserve endangered species.
C) In the short term,hobby aquarium enthusiasts can help by maintaining specimens collected in the wild.
D) In the long term,international measures to control climate change and alleviate drought will help protect amphibian habitats and improve the chances for amphibian survival.
E) In the short term,translocating nonnative amphibians into regions where threatened species are known to exist will help protect habitats for the threatened species.

Question 42

The Global Amphibian Assessment estimates that this fraction of amphibians are threatened with extinction.

A)1/10
B)1/5
C)1/3
D)2/3
E)3/4

Question 43

The sarcopterygian heart had two atria and a partially divided ventricle.Modern amphibians have two atria and an undivided ventricle.This seems like an evolutionary step backwards,but it is not.All of the following statements help us understand why the undivided ventricle is adaptive for amphibians except one.

A)Because gas exchange occurs in the skin of amphibians, venous return of blood to the right side of the amphibian heart is often comprised of oxygenated blood.
B)When an amphibian is submerged, its lungs are not in use.Blood returning to the right side of the heart and leaving the undivided ventricle can be shunted away from the lungs.
C)Blood from the left atrium can bypass the ventricle and go directly into the conus arteriosus and the systemic circulation.
D)Even though we don't understand how it occurs, the spiral valve in the conus arteriosus helps send less oxygenated blood from the right side of the heart to the lungs and more highly oxygenated blood from the left side of the heart to the systemic artery and the rest of the body.This situation is most likely to occur when the amphibian is on land.

Question 44

The retention of juvenile traits throughout the life of the organism is known as

A)amplexus.
B)paedomorphosis.
C)neoteny.
D)parthenogeny.
E)tympanum.

Question 45

Which of the following statements is (are)true regarding the reptiliomorph lineage? Check all that apply.

A) The reptiliomorph lineage includes modern reptiles (including birds)and mammals as well as extinct relatives of these animals.
B) The reptiliomorph lineage includes both amniote and anamniote ancestors.It is possible that we will never know where amniotic membranes arose within this lineage as soft embryonic membranes do not fossilize.
C)Anamniotes are definitely considered to have been reptiles even though they did not have amniotic eggs.Other characteristics are definitely reptilian.
D) Anamniotes had a mix of amphibian/reptilian features including five digit forelegs and an atlas and axis that increased head mobility.Anamniotes are probably basal in position in the lineage they share with amniotes.

Question 46

"Amphibia" means double life,which refers to amphibians dividing their lives between water and land.Which of the statements below accurately reflect how the skin promotes this double life or how it limits the extent to which amphibians can become fully terrestrial? Check all that apply.

A)Scales,warts,and epidermal thickenings that would prevent water loss and promote a more terrestrial lifestyle never occur in amphibians.
B) The skin is very glandular,which helps keep the skin moist.Granular glands secrete toxins that help protect amphibians from predators.
C) The skin is usually very thin and lacks insulating qualities.In water,an amphibian usually takes on the temperature of its surroundings.Out of the water,the thin,vascular skin can quickly warm an amphibian basking in the sun.
D) The thin,moist skin helps us understand why most amphibians are nocturnally active.Even reproductive activities often occur at night.
E) Amphibians on land usually posture themselves erect on all four appendages to promote cooling or warming across their thin skin.
F) Amphibians can remain submerged for long periods,almost indefinitely,because respiratory gases are exchanged across their thin,vascular skin.

Question 47

The transition from fish-to-amphibian involved a series of changes in the vertebrate lineage that are all now very well documented.Which of the following statements accurately reflects our knowledge of these evolutionary events? Check all that apply.

A) Early amphibian fossils,such as Ichthyostega,show important transitional characteristics including mobile neck,loss of opercular bones,appendages with digits,loss of fin rays,and fused sacral vertebrae.
B) Ancient tetrapodomorph fossils,such as Tiktaalik,show important transitional characteristics such as cervical vertebrae,tetrapod-like forelimbs,dorsoventrally compressed skull,and the loss of opercular bones.
C)Molecular analyses,such as the study of the structure of Hox genes,provide powerful evidence supporting evolution of tetrapod appendages.
D) New fossil evidence now indicates that the anurans are basal tetrapods.Higher vertebrates,including mammals,evolved from the frog/toad lineage.
E)We now know precisely the tetrapodomorph species that became the first amphibian.

Question 48

Which gland has been shown to play a key role in the regulation of metamorphosis in amphibians?

A)pancreas
B)thymus
C)thyroid
D)adrenal
E)pineal

Question 49

Which of the following has been suggested as a likely reason for global amphibian decline?

A)ultraviolet radiation
B)environmental pollutants
C)acid deposition
D)urban sprawl
E)all of the answers are correct

Question 50

Amphibians are the "canary in the coal mine" when it comes to monitoring threated species.They are especially vulnerable to environmental threats.All of the following observations help us understand their vulnerable status except one.

A) They are both terrestrial and aquatic, so changes in either environment can potentially harm amphibians.
B) They are insensitive to parasites and other infections, so we know that population declines are related to environmental changes promoted by human activities.
C) They have a thin, vascular, moist skin. Pollutants and other agents can easily penetrate the skin and enter their bodies. They are vulnerable to desiccation.
D) They have both aquatic larval stages and adult stages that may be variously susceptible to environmental disturbances.

Question 51

Vertebrates in the sarcopterygian lineage eventually became fully terrestrial.Three sets of changes in this lineage promoted life on land.Two of these occurred early in the Tetrapodomorpha and are found in all tetrapods.One of these occurred later within the reptiliomorph branch of the tetrapodomorph lineage.Which one of the following is unique to the reptiliomorph lineage?

A)Snap-and-grab feeding modifications of the jaw and jaw musculature
B)Amniotic egg
C)Skeletal modification promoted mobility on land