Which gas is essential for human respiration?
Category: Knowledge · Difficulty: medium
Hint: It's a byproduct of photosynthesis.
Answer
Oxygen
Explanation
Oxygen is vital for respiration in humans and animals, produced by plants during photosynthesis.
This is a medium knowledge riddle — a moderate challenge for most people. The answer is Oxygen.
More Knowledge riddles
- Which Shakespearean play features a character who famously says, 'To be or not to be'?
- What is the approximate length of the Great Wall of China when all its branches are included?
- I can be measured but never seen, created by hands yet I've never been. What am I?
- What two ingredients are typically found in a peanut butter and jelly sandwich?
- I can bark without a dog, and I can lead you to places without a leash. What am I?
- I have hands but cannot clap. I can tell you the time but don’t speak a word. What am I?
- What color is a ripe banana?
- If there are 7 days in a week, 24 hours in a day, and 60 minutes in an hour, how many seconds are in a day?