Question

Elephant seals can hold their breath for over an hour while hunting for food underwater. A researcher wanted to test the hypothesis that seals could spend so much time underwater because they were less sensitive to changes in CO2. Which experiment would be a good way to test the hypothesis? O Increase the buffering capacity of the blood and measure venous CO2 during a dive. O Expose seals to different partial pressures of CO2 before they dive and measure arterial oxygen saturation while they are diving. O Expose seals to different partial pressures of CO2 before they dive and measure how long they stay underwater O Give the elephant seals a drug that increases hemoglobin concentration and measure dive duration.

Answer 1

To test the hypothesis, the researcher can expose seals to different partial pressures of CO2 before they dive and measure how long they stay underwater.

Step-by-step explanation:

To test the hypothesis that elephant seals can spend a long time underwater because they are less sensitive to changes in CO2, the researcher can expose seals to different partial pressures of CO2 before they dive and measure how long they stay underwater. By manipulating the CO2 levels, the researcher can determine if there is a correlation between CO2 sensitivity and dive duration. This experiment would provide direct evidence of the seals' ability to tolerate changes in CO2.

Increasing the buffering capacity of the blood and measuring venous CO2 during a dive would not directly test the hypothesis but would provide information on how CO2 is managed during a dive. Giving the seals a drug that increases hemoglobin concentration and measuring dive duration would also not directly test the hypothesis, but it would provide information on how hemoglobin concentration affects dive duration.

Answer 2

An appropriate experiment to test if elephant seals have lessened sensitivity to CO2 changes would be exposing them to varied CO2 partial pressures before diving and observing their underwater duration.

Step-by-step explanation:

To test the hypothesis that elephant seals can spend extended periods underwater because they are less sensitive to changes in CO2, a suitable experiment would be to expose the seals to different partial pressures of CO2 before they dive and then measure how long they stay underwater. This approach directly assesses the impact of increased CO2 levels on the diving behavior of the seals, which could suggest alterations in their CO2 sensitivity. It is important to measure the duration of their underwater stay, as it reflects the ability of seals to tolerate higher levels of CO2 without surfacing for air. The other proposed experiments, such as increasing buffering capacity, measuring venous CO2 during a dive, measuring arterial oxygen saturation while diving, or giving a drug to increase hemoglobin concentration, do not directly assess sensitivity to CO2 in relation to dive time.