What were the first animals to leave the sea and adapt to a terrestrial environment? When did they do so? What physiological properties did they have that made them able to do so?
What will be an ideal response?
Answer: The first land animals were lobe-finned fish, which made their way onto land during the Devonian Period. These fish possessed internal sacks that could be filled with air to supplement their respiration through gills. They would also have had fins that were strong enough to move overland.
You might also like to view...
An entrepreneur wishes to make a profit by purchasing gold by weight at one altitude and selling it at the same price per newton at another altitude. The entrepreneur should
A. buy at a high altitude and sell at a low altitude. B. buy at a low altitude and sell at a high altitude. C. disregard altitude because it makes no difference. D. none of the above
Which nutrient is most directly responsible for efficient water uptake and conservation?
A) Nitrogen B) Potassium C) Phosphorus D) Titanium
Nebular theory of solar system origin seems to fit the facts more than other theories.
Indicate whether the statement is true or false
Which of the following statements is not true?
A. Except for those living near nuclear plants or uranium mines we are not normally exposed to radiation. B. A given radioisotope behaves chemically just like non-radioactive isotopes of the same element. C. Inferences about the effects of low doses of radiation are drawn, in part, by extrapolation from incidents of high dosage. D. Some radioisotopes are also chemical toxins.