Question

Which adaptation allowed the Tibetans to live at high altitudes?(1 point)
Responses

lower oxygen saturation
lower oxygen saturation

an enlarged right ventricle
an enlarged right ventricle

more efficient hemoglobin in the blood
more efficient hemoglobin in the blood

greater ability to digest starch

Answer 1

The adaptation that allowed the Tibetans to live at high altitudes is **more efficient hemoglobin in the blood**. This adaptation helps them effectively use the limited oxygen available at high elevations.

Answer 2

Tibetans’ physiological adaptations make them less likely to suffer from(1 point)
Responses

altitude sickness.
altitude sickness.

blood clots.
blood clots.

pulmonary hypertension (or high blood pressure).
pulmonary hypertension (or high blood pressure).

heart attacks.

Answer 3

Tibetans’ physiological adaptations make them less likely to suffer from **pulmonary hypertension (or high blood pressure)**. Their bodies have adapted to high-altitude conditions, reducing the risk of complications associated with low oxygen levels, including pulmonary hypertension.

Answer 4

Which data would be the best evidence to support the claim that natural selection was still occurring in human populations?(1 point)
Responses

With better medical technology, more people are surviving for longer periods of time, which has dramatically increased the human population.
With better medical technology, more people are surviving for longer periods of time, which has dramatically increased the human population.

Because humans spend more time with digital technology, more people suffer with eye strain compared to previous generations.
Because humans spend more time with digital technology, more people suffer with eye strain compared to previous generations.

Natural disasters have become more intense over the years, which has caused people to move away from certain regions of the planet.
Natural disasters have become more intense over the years, which has caused people to move away from certain regions of the planet.

Hotter temperatures during the summer months cause more deaths, and survivors tend to give birth to children that are more resistant to heat.

Answer 5

The best evidence to support the claim that natural selection was still occurring in human populations is: **Hotter temperatures during the summer months cause more deaths, and survivors tend to give birth to children that are more resistant to heat.** This response indicates a survival advantage leading to potential evolutionary changes in the population, which is a core principle of natural selection.

Answer 6

What do populations living at high elevations have to adapt to?(1 point)
Responses

higher average temperatures.
higher average temperatures.

higher heart rates among children.
higher heart rates among children.

lower ultraviolet light intensity.
lower ultraviolet light intensity.

lower oxygen levels.

Answer 7

Populations living at high elevations have to adapt to **lower oxygen levels**. At high altitudes, the air contains less oxygen, which can pose challenges for respiration and adaptation.

Answer 8

An enlarged right ventricle both increases oxygen intake and the risk of pulmonary hypertension. How can natural selection result in an adaption that produces both positive and negative effects?(1 point)
Responses

The negative effects appear before reproductive age in certain environments.
The negative effects appear before reproductive age in certain environments.

The positive effects outweigh the negative effects in certain environments.
The positive effects outweigh the negative effects in certain environments.

The negative effects appear later in life in certain environments.
The negative effects appear later in life in certain environments.

The positive effects appear after reproductive age in certain environments.

Answer 9

Natural selection can result in an adaptation that produces both positive and negative effects because **the negative effects appear later in life in certain environments.** If the beneficial effects of an adaptation enhance reproductive success before the negative effects manifest, the adaptation can be favored by natural selection despite its later drawbacks.