Daily challenge · 15 October 2026
Science and nature
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Question 1
What is a young frog called before it develops legs?
- A A tadpole
- B A newt
- C A polliwog's egg
- D A toadlet
A frog's aquatic larval stage is called a tadpole.
Question 2
In a compound microscope, which lens is closest to the specimen?
- A The eyepiece
- B The objective lens
- C The condenser
- D The field lens
The objective lens sits near the specimen and forms the first magnified image.
Question 3
What is another name for the aurora australis?
- A The northern lights
- B The southern lights
- C The zodiacal light
- D The gegenschein
Aurora australis is commonly called the southern lights.
Question 4
Which plant did Gregor Mendel use in his classic inheritance experiments?
- A Garden peas
- B Corn
- C Snapdragons
- D Fruit flies
Mendel studied garden pea plants, whose contrasting traits were useful for tracking inheritance.
Question 5
Which NASA spacecraft became the first lander to operate successfully on the surface of Mars?
- A Viking 1
- B Mars Pathfinder
- C Sojourner
- D Phoenix
Viking 1 landed in 1976 and returned data from the Martian surface.
Question 6
What does a spectrograph separate light into for analysis?
- A Different wavelengths
- B Different temperatures
- C Different magnetic fields
- D Different directions of gravity
A spectrograph spreads light into its component wavelengths, producing a spectrum.
Question 7
What is the scientific study of tree rings called?
- A Palynology
- B Dendrochronology
- C Limnology
- D Phenology
Dendrochronology uses tree rings to study growth and date wood.
Question 8
Which enzyme joins DNA fragments by sealing breaks in the sugar-phosphate backbone?
- A DNA ligase
- B DNA helicase
- C RNA polymerase
- D Restriction enzyme
DNA ligase seals breaks in DNA strands, including joins between DNA fragments.
Question 9
Which spacecraft returned the first samples from an asteroid to Earth?
- A Hayabusa
- B OSIRIS-REx
- C Stardust
- D Hayabusa2
Japan's Hayabusa mission returned particles from asteroid Itokawa in 2010.
Final question
What is the name of the protein complex in photosystem II that catalyzes the splitting of water during photosynthesis?
- A The cytochrome b6f complex
- B The oxygen-evolving complex
- C The ATP synthase complex
- D The reaction center of photosystem I
The oxygen-evolving complex, which contains a manganese-calcium cluster, extracts electrons from water in photosystem II.