The mechanism for excreting nitrogenous waste in aquatic animals was ineffective on land because
A) land animals concurrently developed a more efficient reproduction system.
B) land animals found better food sources.
C) land animals had a more difficult time with water balance than aquatic species.
D) aquatic animals did not have as much protein in their diets as did land animals.
Answer: C
You might also like to view...
In negative control, a gene is switched off when _____
A) a kinase adds a phosphate to DNA B) lactose is transported into the cell C) a regulatory protein binds to DNA and shuts down transcription D) a regulatory protein is removed from DNA and shuts down transcription
The EIA test for HIV infection is a direct test for HIV envelope proteins
Indicate whether the statement is true or false.
The present rate of species loss ________
A) suggests that about 25% of all plant and animal species may be extinct by the end of the century B) is about the same as it has been during the last 100,000 years C) is as much as 100 times higher than at any time in the last 100,000 years D) is slower than in recent years because of conservation efforts
All of the following are characteristics that make plasmids good cloning vectors, except
A. they are well characterized. B. they can accept a relatively large amount of foreign DNA. C. they are small. D. they can be transferred into appropriate host cells. E. they can carry genetic markers, such as antibiotic resistance genes.