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Why do some cacti take in carbon dioxide at night?

A saguaro takes in carbon dioxide during the cooler night, storing carbon in organic acids for use in daylight. This timing helps connect photosynthesis with the challenge of conserving water. Explore how CAM plants separate steps that many other plants perform during the day.

4–5 min

Questions you could explore

  • What is stored overnight, and what happens to it in daylight?
  • How can that timing help with water loss?

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Nature and biology

How does a honey bee dance give directions?

A returning honey bee can communicate about food without leading every other bee to it. The direction and duration of its waggle dance carry information that other bees can use beyond the dark hive.

3–5 min

How does a honey bee dance give directions?

Nature and biology3–5 minA returning honey bee can communicate about food without leading every other bee to it. The direction and duration of its waggle dance carry information that other bees can use beyond the dark hive.

Nature and biology

How can an octopus change color so quickly?

An octopus can alter the appearance of its skin far faster than a new coat of pigment could grow. Tiny structures already in the skin control what becomes visible, with pigment and reflected light playing different roles.

5–7 min

How can an octopus change color so quickly?

Nature and biology5–7 minAn octopus can alter the appearance of its skin far faster than a new coat of pigment could grow. Tiny structures already in the skin control what becomes visible, with pigment and reflected light playing different roles.

Nature and biology

Finding prey through returning echoes

An echolocating bat uses the delay and character of returning sound to follow a target. Its calls can change as it approaches prey, connecting the sound it sends with the information it needs next.

3–5 min

Finding prey through returning echoes

Nature and biology3–5 minAn echolocating bat uses the delay and character of returning sound to follow a target. Its calls can change as it approaches prey, connecting the sound it sends with the information it needs next.

Why do some cacti take in carbon dioxide at night? | Speech Topic | speaking.app