What is it called when a seed starts to sprout?
AnswerGermination
A sprouting seed absorbs water, swells and sends out its first root and shoot.
Nature · Facts & stats
Growth facts & stats
7 fact-checked facts about growth in plants and living things, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
Which gas do green plants release into the air when they make food using sunlight?
AnswerOxygen
Most of the oxygen in Earth's air was produced by plants, algae and cyanobacteria over billions of years.
Going deeper
Which group includes some of the fastest-growing plants on Earth, with some species growing nearly a metre in a day?
AnswerBamboos
These giant grasses grow extremely fast because many segments of the stem lengthen at the same time.
In a plant, which tissue carries water up from the roots?
AnswerXylem
Xylem vessels move water and minerals upward, while phloem carries sugars around the plant.
The spirals in a sunflower head usually come in numbers from which famous sequence?
AnswerFibonacci sequence
Counting the spirals in each direction often gives neighboring numbers in the sequence, such as 34 and 55.
Expert level
If a population doubles every 10 years, how many times larger is it after 30 years?
Answer8 times
Three doublings give 2 × 2 × 2 = 8 times the starting size, which is how exponential growth works.
Which gland in the human body produces growth hormone?
AnswerPituitary gland
This pea-sized gland at the base of the brain releases growth hormone, much of it during sleep.
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