Question

1) The Shark's spiral valve (choose all that apply)

A) Keeps water out of the nostrils

B) is located in the intestine

C) is located in the stomach

D) Increased surface area for digestion/nutrient absorption

E) Provides buoyancy and increased efficiency of swimming

F) Allows water to flow over the gills

2) The closest extant organism that evolutionarily links fish and amphibians is:

A) salamanders

B) caecilians

C) acanthostega

D) conodonts

E) Lamprey

F) Lungfish

3) Animals that have body temperature dependent on the environments (Choose all that apply)

A) are endotherms

B) are homeotherms

C) are ectotherms

D) eat a lot to meet their high energy needs

E) Eat less due to low energy needs

F) Fish & sharks

G) Amphibians & reptiles

H) Birds

4) Fish and amphibians SHARE which of these characteristics: (Choose all that apply)

A) chordates

B) vertebrates

C) endotherms

D) poikilotherms

E) deuterostomes

F) Protostomes

G) Scaley skin

H) Amniotes

5) Which of the following characteristics are shared by a hagfish and a lamphrey? (choose all that apply)

A) a rasping tongue

B) paired fins

C) jaws

D) a notochord

E) Scaled skin

F) Gills

G) operculum

Answer 1

1. Sharks have spiral valve present in there colon of intestine,which help in the digestion and absorption of food by increasing the surface area of absorption.Thus B and D are correct.

2.Lungfish Protopterus is the connecting link between fishes and amphibians because it has fish like appearance, paired fins and also has amphibians like characters like internal nostrils, lungs and heart.Thus F is correct.

3.Organisms which can not regulate of maintain there body temperature are known as poikilotherms (cold blooded animals) or ectotherms .and due to lack of regulation of body temperature they require external source for the heat also they require very less amount of energy for survival ,thus they eat less food.Most fish, invertebrates,reptiles, and amphibians are ectothermic poikilotherms.Thus Option C,E,F,and G are correct .

4.All chordates are deuterostomes ,so fishes and amphibian are deuterostomes,poikilothermic , contain vertebral column thus are vertebrates.Fishes and amphibians are lower vertebrates and they lay anamniotic eggs,Amniotes includes the higher vertebrates such as reptiles, Aves,mammals as they lay amniotic eggs.Scales are present in the fishes but they are absent in the amphibians .Thus A ,B ,D E and H are correct.

5.Hagfish and Lamprey are the jawless fishes having operculum covering the gills and act as respiratory and feeding structure .They have elongated eel like, scaleless body structure and notochord is present in them.Thus D,F and G are correct.