Question

select all the correct answers.
what are three examples of negative feedback loops in earth’s environment?

• ice reflects radiation, decreasing temperatures in the atmosphere. this results in more ice formation
• as predators catch more prey, the number of prey decreases. this causes some predators to starve and eventually die.
• when ice begins to melt, it absorbs more radiation. this causes the ice to melt faster
• as more carbon builds up in the atmosphere, more of it gets absorbed by the oceans. this results in less carbon in the atmosphere
• as the population of a water plant rapidly increases, new offspring are unable to get enough sunlight. this results in a sudden increase in the plant’s death rate

Explanation:

1. Ice reflects radiation...: Negative feedback (cooler temps → more ice, which reflects more, cooling further? Wait, no—wait, ice reflects, so more ice → less radiation absorbed → cooler, which makes more ice. Wait, actually, this is a negative feedback? Wait, no, let's recheck. Wait, negative feedback loops counteract changes. Let's analyze each:

• Ice reflects radiation, decreasing temperatures... more ice: Wait, if ice reflects, temp drops, leading to more ice. But this is a positive feedback? Wait, no, maybe I messed up. Wait, let's check the other options.
• Predators catch more prey... prey decreases... predators starve/die: As prey decreases, predator population decreases (since they starve), which allows prey to recover. This is negative feedback (stabilizes predator-prey population).
• Ice melts, absorbs more radiation... melts faster: This is positive feedback (melting leads to more melting).
• More carbon in atmosphere... oceans absorb more... less carbon in atmosphere: Carbon increase → ocean absorption increases → atmospheric carbon decreases. This counteracts the initial increase, so negative feedback.
• Water plant population increases... new offspring no sunlight... death rate increase: As plant population grows, resources (sunlight) become scarce, leading to higher death rate, which stabilizes population. This is negative feedback (counteracts population growth).

Wait, initial analysis of the first option: "Ice reflects radiation, decreasing temperatures in the atmosphere. This results in more ice formation." Wait, if temp decreases, more ice forms, which reflects more radiation, leading to even lower temps? That would be positive feedback (amplifying the cooling). Wait, maybe I made a mistake. Let's re-express negative feedback: a change in a variable leads to processes that reverse the change.

• Predator-prey: Prey ↓ → Predator ↓ (since they starve) → Prey can recover. So prey decrease is reversed (since predator decrease allows prey to increase). So negative feedback.
• Carbon-ocean: Carbon ↑ → Ocean absorbs ↑ → Carbon ↓. So carbon increase is reversed. Negative feedback.
• Water plant: Population ↑ → Sunlight scarce → Death rate ↑ → Population ↓. So population increase is reversed. Negative feedback.
• First ice option: Ice ↑ → Temp ↓ → Ice ↑ (more ice). So temp decrease leads to more ice, which leads to more temp decrease. That's positive feedback (amplifying the cooling).
• Melting ice: Ice ↓ → Absorb more radiation → Temp ↑ → Ice ↓ more. Positive feedback.

So the correct ones are:

• As predators catch more prey... (predator-prey)
• As more carbon builds up... (carbon-ocean)
• As the population of a water plant... (plant population)

Wait, but let's check the first ice option again. Maybe the question's first option is worded as "decreasing temperatures in the atmosphere. This results in more ice formation." So temp decreases (due to ice reflecting) → more ice. But does more ice lead to less radiation absorbed, so temp decreases further? That's positive feedback. So the first option is positive, not negative. So the three correct are:

1. As predators catch more prey, the number of prey decreases. This causes some predators to starve and eventually die.
2. As more carbon builds up in the atmosphere, more of it gets absorbed by the oceans. This results in less carbon in the atmosphere.
3. As the population of a water plant rapidly increases, new offspring are unable to get enough sunlight. This results in a sudden increase in the plant’s death rate.

Answer:

• As predators catch more prey, the number of prey decreases. This causes some predators to starve and eventually die.
• As more carbon builds up in the atmosphere, more of it gets absorbed by the oceans. This results in less carbon in the atmosphere.
• As the population of a water plant rapidly increases, new offspring are unable to get enough sunlight. This results in a sudden increase in the plant’s death rate.