Daily challenge · 29 October 2026
Science and nature
0 players took on this challenge.
Question 1
Corals and sea anemones belong to which animal group?
- A Molluscs
- B Cnidarians
- C Arthropods
- D Echinoderms
Corals and sea anemones are cnidarians, a group that also includes jellyfish.
Question 2
What substance is a major component of the cell walls of fungi?
- A Cellulose
- B Chitin
- C Keratin
- D Silica
Fungal cell walls contain chitin, the same tough material found in the external skeletons of many arthropods.
Question 3
In what year did Edward Jenner perform the experiment commonly regarded as the first vaccination against smallpox?
- A 1761
- B 1796
- C 1824
- D 1858
In 1796, Jenner inoculated a boy with material from cowpox lesions and later tested his protection against smallpox.
Question 4
What term describes the independent evolution of similar features in distantly related organisms?
- A Genetic drift
- B Convergent evolution
- C Artificial selection
- D Co-evolution
Convergent evolution occurs when similar traits evolve independently, often because organisms face similar environmental pressures.
Question 5
What is the name of the process by which plants release water vapor, mainly through pores in their leaves?
- A Transpiration
- B Germination
- C Fermentation
- D Translocation
During transpiration, water evaporates from plant tissues and escapes chiefly through leaf pores called stomata.
Question 6
In genetics, what is the inheritance pattern called when a heterozygote has an intermediate phenotype between the two homozygotes?
- A Codominance
- B Incomplete dominance
- C Sex linkage
- D Epistasis
With incomplete dominance, neither allele fully masks the other, so the heterozygote shows an intermediate phenotype.
Question 7
Because of the Coriolis effect, moving air is deflected in which direction in the Northern Hemisphere?
- A To the left
- B To the right
- C Toward the equator only
- D Straight upward
Earth's rotation causes moving air to be deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.
Question 8
Which spacecraft made the first successful landing on a comet's surface, in 2014?
- A Huygens
- B Philae
- C Hayabusa2
- D Viking 1
The Philae lander, carried by the Rosetta mission, made the first successful landing on a comet when it reached Comet 67P in 2014.
Question 9
The 1953 Miller–Urey experiment produced which kind of organic molecules from a mixture of gases and water exposed to electrical sparks?
- A Amino acids
- B DNA strands
- C Cell membranes
- D Chlorophyll
The experiment produced amino acids and other organic compounds under laboratory conditions intended to represent aspects of early Earth.
Final question
Approximately how old is the Vredefort impact structure in South Africa, the largest confirmed impact structure on Earth?
- A 202 million years
- B 660 million years
- C 2.02 billion years
- D 4.1 billion years
The Vredefort impact structure formed about 2.02 billion years ago.