Question

URGENT!!!!!

You are once again the science officer stationed on the starship NX-01. Upon discovery of a new planet, the mission of you team is to conduct a survey of the resources found on the planet. Now that you have conducted an ecological analysis of the planet, you have been called upon to some examine some of the living organisms on the planet. The area your team has been assigned to explore is located on East Darwin near the coast. The seawater is salty, approximately the same concentration as the seas on earth. Inland from the sea is a dry desert region with very little fresh water available. Between the desert and the sea are patches of scrubby grass, averaging approximately 35 cm in height.

While exploring the coastal areas of east Darwin, you find the remains of a large organism on the beach. The body is approximately 25m long, and appears to be some type of vertebrate-like organism. The organism has four relatively short limbs, attached to a heavy pectoral and pelvic girdle. Because of it’s location, you are at first unsure if it is an aquatic organism that washed up on the beach, or a terrestrial organism that died near the seashore. What respiratory, circulatory excretory and, structural features would you look for during your dissection to determine if it was aquatic or terrestrial? Explain why the structures you have mentioned are important in determining aquatic or terrestrial origins for the organism? (10 pts)

Describe some of the problems associated with the size of the organism mentioned in question #1. In your answer, address possible problems with movement, transfer of heat energy generated by the body and movement of materials across the epidermis. You must refer to the square cube law in your answer. If you answered terrestrial in question 1 assume your organism is terrestrial for question 2 as well. If you answered aquatic in question 1, assume your organism is aquatic for question 2 as well. (10)

In a stream you are observing, you see a living organism that appears to be Catadromous. Explain what this means for their physiology? (5)

These aquatic organisms can sense their environment in a variety of different ways. Discuss two different sensory systems that aquatic organisms may have that humans do not have. (5)

While continuing to explore your assigned area, you come across a small 4-legged organism (approximately 40 cm high, weight approximately 6 kg) with a feather-like outer covering. It inhabits the scrubby grass strips between the sea and the desert. As you observe the animal, you notice that after grazing on the grass, it walks to the sea and drinks the water. What adaptations might this organism have to be able to drink seawater? Explain. (10)

You are to travel to the cold regions in far north of the planet for your final explorations before you return to Earth from your continuing mission. Would you expect to large, small animals, both or none in this region? Why? (10)

Answer 1

Ans-1 the organism should have closed circulatory system and a well developed heart. The respiratory system will consist the lungs and a wind pipe. The excretory system will show to be urotelic and the limbs will be specialised for walking or running if it have a terrestrial origin but if it have aquatic origin then it would be having an open circulatory system and respiratory system will be having gills and the excreatory system will be amonotelic. The limbs will be specialised for swimming.

But as it's length is 25 m so possibly it must be an aquatic organism.

Ans-2 as stated in question that the organism is having a size of 25 m which is a very large size. According to square cube law it is having a large surface area so the heat transfer will be at a high rate and movement of other substance will also be at a high rate as surface area is large. It will be having difficulty in the movement as it will need more energy to move this much body mass.

Ans-3 catadromus means the fish like eel they migrate to sea from the rivers for the process of spawning. These fishes are born in the sea water or salty water from where they reach to fresh water in their juvenile age and stay up to their adulthood and after attaining a mature age they migrate back to the sea for the spawning.

Ans-4 they have sensory organs in respiratory system and skin which can sense any danger from the water flow. The changes in water current act as a signal for various organisms.

Some of them send waves likes bats and these waves return back after encountering some resistance and travel back as echo this also help organism in sensing the location of some object lying in their movement direction.