Quiz of the Day
Botany, Plants & Weird Science
Monday, 27 July 2026
They breathe, feel, and communicate — surprising truths about the plant kingdom you never expected
1. Plants respond to sound and vibrations. Research has shown that playing which type of music tends to stimulate plant growth?
- Heavy metal
- Both classical and heavy metal show effects in some studies
- Classical music
- Ambient sounds
Studies have found plants respond to sound frequencies between 100-500 Hz, which overlap both classical and certain heavy metal frequencies. One South Korean study found plants grew faster with both genres compared to silence. Scientists believe vibrations may mimic wind, triggering hormonal responses that strengthen stem growth.
2. The Venus flytrap closes its trap when an insect touches trigger hairs not once but a minimum of how many times?
- Twice
- Three times
- Five times
- Once
The Venus flytrap has evolved a counting mechanism — two touches within about 20 seconds trigger closure, preventing false alarms from raindrops. After closure, it counts further stimulations: at five or more, it knows something is inside and begins producing digestive enzymes. This plant 'counts' without a nervous system.
3. Which gas do plants release at night, when photosynthesis stops?
- Methane
- Carbon dioxide
- Oxygen
- Nitrogen
During the day, plants absorb CO₂ for photosynthesis and release O₂. At night, only respiration occurs — consuming O₂ and releasing CO₂, the same as animals. The net effect over 24 hours is still positive for oxygen production, but the old idea of never putting plants in a bedroom is based on this night-time CO₂ release.
4. The world's largest organism by area is a fungus — but the world's largest plant is a seagrass meadow in Australia. What species is it?
- Posidonia australis
- Cymodocea nodosa
- Thalassia testudinum
- Zostera marina
A single Posidonia australis clone in Shark Bay, Western Australia was discovered in 2022 to cover approximately 180 km² — making it the world's largest known plant. It grew from a single seed and has been spreading by clonal reproduction for about 4,500 years. Despite sexual reproduction being possible, this individual appears to have produced no seeds.
5. What is 'allelopathy' in botany?
- The attraction of plants to sunlight
- The process of seed dispersal by animals
- The reaction of plants to touch
- The release of chemicals by plants to inhibit competitors
Many plants practice chemical warfare — releasing substances through roots or leaves that slow the growth of competing species. Black walnut trees famously produce juglone, toxic to many garden plants. Garlic mustard, an invasive species in North America, releases allelopathic chemicals that disrupt the fungal networks native plants depend on.
6. The baobab tree, called the 'tree of life' in Africa, can store how much water in its trunk?
- Up to 500,000 litres
- Up to 120,000 litres
- Up to 2,000 litres
- Up to 500 litres
Large baobabs can store up to 120,000 litres of water in their swollen trunks — an extraordinary adaptation to seasonal drought. They can live for over 2,000 years. Communities in Southern Africa traditionally built homes and bars inside hollowed-out living baobab trees, some of which had natural cavities large enough for 30 people.
7. Research by Suzanne Simard revealed that trees in forests communicate and share resources through underground fungal networks called what?
- Root networks
- Spore highways
- Wood wide web
- Mycorrhizal networks
Simard's research showed that 'mother trees' — large, old trees — send carbon and nutrients to seedlings through mycorrhizal fungal networks, preferentially to their own kin. The popular term 'wood wide web' was coined by scientists to describe this inter-plant communication and resource-sharing system. It fundamentally changed how ecologists view forests.
8. The Mimosa pudica plant, known as the 'sensitive plant,' folds its leaves when touched. What is this response called?
- Thigmotropism
- Phototropism
- Nyctinasty
- Seismonasty
The Mimosa's rapid leaf-folding response is seismonasty — movement in response to shock or vibration. It happens because cells in the leaf joints rapidly lose water, causing collapse. Research found that Mimosa can be 'trained' to stop responding to a repeated harmless stimulus — demonstrating a simple form of learning without a brain.
9. Which plant is used to make around 70% of the world's chocolate supply?
- Cacao nacional
- Cacao forastero
- Cacao trinitario
- Cacao criollo
Forastero produces the bulk of commercial chocolate — it's hardy, high-yielding, and disease-resistant, though it has a less complex flavour than the premium Criollo variety. Fine chocolate makers seek out rarer Criollo or Trinitario varieties for their superior flavour complexity. The entire cocoa crop is threatened by climate change and the spread of Witches' broom disease.
10. Which plant family contains the most species of any flowering plant family on Earth?
- Asteraceae (daisies)
- Orchidaceae (orchids)
- Rosaceae (roses)
- Fabaceae (legumes)
There are approximately 28,000 species of orchid — more than all bird and mammal species combined. Orchids have evolved extraordinary pollination strategies, including mimicking female wasps to attract male wasps who attempt to mate with the flower and inadvertently carry pollen. Some orchids produce no nectar and rely entirely on deception.
11. Photosynthesis converts carbon dioxide and water into glucose and oxygen using energy from sunlight. What is the efficiency of photosynthesis at converting light to chemical energy?
- About 30-40%
- About 1-2%
- About 10-15%
- About 50-60%
Most plants convert only 1-2% of incident solar energy into chemical energy through photosynthesis — far less efficient than solar panels (15-25%). However, the total scale is staggering: plants fix about 120 billion tonnes of carbon per year globally. Researchers are working on 'artificial photosynthesis' that might achieve efficiencies of 10-20%.
12. The pitcher plant drowns insects in its digestive fluid. What prevents the plant from digesting itself?
- The digestive enzymes only activate when insects are present
- The walls are made of indigestible cellulose that enzymes can't break down
- The inner surface is coated in mucilage
- The walls are coated in wax
Pitcher plants produce enzymes similar to those in animal stomachs, but the plant's own cell walls are made of cellulose, lignin, and chitin — materials the enzymes can't digest. The plant tissue also has acid-resistant coatings. Some pitcher plants have evolved to trap and digest rats, lizards, and even small birds — their pitchers reaching 30 cm in depth.
13. The oldest living individual tree in the world, 'Methuselah,' is a Great Basin bristlecone pine. Approximately how old is it?
- 1,500 years
- 6,200 years
- 2,700 years
- 4,800 years
Methuselah is located in the Inyo National Forest in California and was approximately 4,855 years old as of 2024. Its exact location is kept secret to protect it from visitors. Older trees have been found — one was dated to 5,067 years — but have not been officially verified. These trees were already ancient when the Egyptian pyramids were built.
14. The 'corpse flower' (Amorphophallus titanum) produces the world's largest unbranched inflorescence and smells like rotting flesh. How often does it typically bloom?
- Every year
- Every 3-5 years
- Every 7-10 years
- Only once in its lifetime
The corpse flower blooms only every 7-10 years, and the bloom lasts just 24-48 hours during which it heats itself to body temperature to project the rotting smell further, attracting dung beetles and carrion flies as pollinators. Botanical gardens draw enormous crowds when one blooms — people queuing for hours for a few seconds of the smell.
15. Why do leaves change colour in autumn in temperate regions?
- They absorb more sunlight to generate heat
- They produce new red and yellow pigments in response to cold
- The green chlorophyll breaks down, revealing underlying pigments
- Insects feeding on leaves cause pigment changes
Green chlorophyll dominates in summer, masking other pigments. As days shorten, trees begin shutting down leaf production, stopping chlorophyll production. As it degrades, yellow and orange carotenoids (always present) are revealed. Red anthocyanins are actually newly produced as the tree reclaims nutrients from leaves before they fall — using sugar to make the pigment.