--- title: Sharks — a lesson of Mova's school · trees and pragmatics description: «Sharks», a lesson of the biology course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: A shark is a fish with no bones at all: its skeleton is cartilage, the bendy stuff in your nose and ears, so it is light and flexible, and because cartilage rots a --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/biology/28-sharks/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/) / Sharks # Sharks Lesson 28 of the biology course of Mova's primary school: 19 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](https://md.mova.elamur.ai/free/en/school-run/biology/28-sharks/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/0/) — A shark is a fish with no bones at all: its skeleton is cartilage, the bendy stuff in your nose and ears, so it is light and flexible, and because cartilage rots away, shark fossils are mostly teeth. - [1](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/1/) — Those teeth sit in rows like a conveyor belt; when one breaks a new one moves forward, so some sharks lose tens of thousands in a lifetime, and that is why a sandy beach can be full of tiny black shark teeth. - [2](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/2/) — Sharks have senses you don't: pores on the snout, the ampullae of Lorenzini, feel the faint electricity of a fish's muscles, so a shark can find a fish hiding under the sand. - [3](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/3/) — Films like Jaws show sharks hunting people; in truth, sharks kill only a handful of people a year, usually by mistaking a swimmer for a seal, while people kill around 100 million sharks a year. - [4](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/4/) — And the biggest shark of all, the whale shark, up to 12 to 18 metres long, eats only plankton and tiny fish and lets snorkellers swim beside it. - [5](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/5/) — Sharks lose teeth all the time and grow new ones from the rows behind, some tens of thousands in a lifetime. - [6](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/6/) — A shark's skeleton is made of cartilage, which is lighter and bendier than bone, so shark fossils are mostly teeth. - [7](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/7/) — Great white sharks often attack seals from below and can burst right out of the water; they grow to about 6 metres and can live over 70 years. - [8](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/8/) — Sharks smell blood well, but the story that they can smell one drop from miles away is exaggerated. - [9](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/9/) — Sharks don't hunt humans; bites are very rare and often a mistake, and people kill around 100 million sharks a year. - [10](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/10/) — The whale shark is the biggest fish in the world, up to about 12 to 18 metres, filters plankton and is harmless to people. - [11](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/11/) — Some sharks, like great whites and makos, must keep swimming to push water over their gills, while nurse sharks can rest on the bottom. - [12](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/12/) — Sharks have no swim bladder, so many sink if they stop swimming. - [13](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/13/) — Sharks sense the faint electricity of living animals with pores on their snouts called the ampullae of Lorenzini. - [14](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/14/) — Shark skin is covered in tiny tooth-like scales called dermal denticles that help water flow smoothly, and some swimsuits copy them. - [15](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/15/) — Hammerheads have eyes at the ends of a wide flat head, which gives better all-round vision and spreads out their electric sensors. - [16](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/16/) — The Greenland shark is the longest-living animal with a backbone known, probably at least 270 years, growing about a centimetre a year. - [17](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/17/) — Some sharks and rays lay eggs in leathery cases called mermaid's purses, while other sharks give birth to live pups. - [18](https://md.mova.elamur.ai/free/en/corpora/school/biology/28-sharks/18/) — Many sharks are endangered because they grow slowly and have few young, and they keep oceans healthy by eating sick fish. - ← previous: [Dolphins, porpoises and seals](https://md.mova.elamur.ai/free/en/corpora/school/biology/27-dolphins-porpoises-and-seals/) - next →: [Crocodiles and alligators](https://md.mova.elamur.ai/free/en/corpora/school/biology/29-crocodiles-and-alligators/) - ↑ back to [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/)