Question

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. Q1 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 featureswould 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) Q2 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) Q3 In a stream you are observing, you see a living organism that appears to be Catadromous. Explain what this means for their physiology? (5) Q4 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)

Answer 1

Ans 1) There are a lot of analysis that needs to be done to find out if it is terrestrial or aquatic animals. The respiratory system for both is different from each other. In the terrestrial animals have lungs or other organs that are similar to lungs which help in the process of breathing. The mammal pulls air into their lungs and breathes. The respiration in aquatic animals generally takes place either through skin or their gills. This is the first step into understanding if it is an aquatic or terrestrial animal. The marine vertebrates have a postanal tail which is used for movement. It has a vertebral column that develops from the notochord and a closed loop circulatory system. They have limbs and lungs that help it to adapt to the terrestrial life. Due to the presence of the limbs, it is most likely to be a terrestrial invertebrate.