Trees Lesson 60 of the biology course of Mova's primary school: 16 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: the lesson at school .
1 Count the rings on a stump in the woods and you know its age: each year makes one ring, pale wood from fast spring growth and darker wood from slower late summer; a wide ring was a good year, a thin one a hard year. 2 Trees are the record breakers of the living world: bristlecone pines over 4800 years old, a redwood called Hyperion about 116 metres tall, and a single oak that is home to more than 2000 kinds of living things. 3 Most of a tree is made from the air: it takes in carbon dioxide, keeps the carbon in its wood and gives out oxygen, which is why old forests matter so much for the climate. 4 Cartoons show trees as lonely and silent; under the ground their roots are joined to fungi that swap water and minerals for sugar, and some scientists think trees may share food this way, though how much is still argued about. 5 Each year a tree grows a new ring of wood under its bark; scientists use tree rings to learn about the weather hundreds or thousands of years ago. 6 Some Great Basin bristlecone pines in California are over 4800 years old; they grow very slowly in a cold, dry place where few pests survive, and slow-grown wood is dense and tough. 7 The tallest known living tree is a coast redwood called Hyperion, about 116 metres tall, and the giant sequoia General Sherman is the biggest by volume; much taller is hard for any tree, because lifting water up to the top leaves gets too hard. 8 Bark protects the living wood from insects, disease, fire and cold, and under it a thin living layer makes new wood and bark; cutting a ring of bark all round can kill a tree. 9 Cork comes from the thick bark of the cork oak, peeled about every 9 years without killing the tree. 10 An oak gall forms when a tiny wasp lays an egg in an oak bud and the tree grows a ball round it; for centuries people made black ink from oak galls. 11 Pine cones open their scales in dry weather to let winged seeds blow away, since seeds travel best on dry windy days, and close in damp air and rain; some open only after a forest fire. 12 Deciduous trees drop their leaves in autumn and protect next year's tiny leaves and flowers inside buds wrapped in tough scales; horse chestnut buds are glued shut and sticky, and conkers are poisonous to eat. 13 Beech trees make a thick roof of leaves, so little grows beneath them except plants like bluebells that flower in spring before the beech leaves open. 14 Many tree roots are joined to fungi, a link sometimes called the «wood wide web»; the mushrooms are only the fruit of a much bigger fungus underground, and wild mushrooms must never be picked or eaten as some are deadly. 15 The baobab stores large amounts of water in its spongy trunk to survive months without rain, drops its leaves in the dry season so it does not lose water through them, and some baobabs are over 1000 years old. 16 Rainforests cover only about 6 percent of the land but hold more than half of all the kinds of land plants and animals, and most of the animals live up in the canopy, where most of the fruit, flowers and leaves are. ← previous Seeds and fruit and how they travelnext → Carnivorous and strange plants↑ back to Biology This page in Markdown → https://md.mova.elamur.ai/free/en/corpora/school/biology/60-trees/