Dr. digger, a paleontologist, finds a fossil that he describes in his journal. the creature was approximately 1 meter long, with its backbone fused into a large shell covering the body cavity. it had a beaklike mouth, without teeth, and all four limbs were in the form of flippers. based on anatomical similarities, to which modern animal is dr. digger’s creature most closely related?
a. zebra
b. bony fish
c. sea turtle
d. snake

Ans.

The fossil found by Dr. Digger was about 1 meter long, with backbone, body cavity covered by shell, beaklike mouth with no teeth. Along with these characters, it also had four limbs that were present in the form of flippers. All these features are present in a sea turtle as sea turtle is a tetrapod, its body cavity is protected by a hard shell made up of many bones, and it has flippers that help in swimming.  

Hence, the correct answer is option 'c). sea turtle.'

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.

i think the answer is c hope this