Дистанційне навчання 6-Д Pace Work (Science) 31/03/2021

Theme: Fossils.

In order to learn new items we start to work with lexical cards. (cards #1) Here you can see some new words:

- a fossil – the remains or impression of a (usu. prehistoric) plant or animal hardened in rock

- extinct – without a survivor; without force; dead

- mammoths – any of several species of extinct elephant s whose fossils have been found in Pleistocene deposits (beginning 1.8 million years ago) on every continent.

- resin – a sticky substance that is produced by some trees

- leach – to dissolve out soluble constituents from (ashes, soil, etc.) by percolation; to cause (water or other liquid) to percolate through something.

- fossilization – noun the process of converting, or of being converted, into a fossil.

Reading

  Now we are going to read the text.

Fossils

     Fossils are the actual remains of plants or animals or the petrified traces of plants or animals.

Giant woolly creatures, called mammoths, have been found perfectly preserved in frozen soil. The mammoth is an animal now extinct. Extinct means no longer existing. The mammoth was a large type of elephant which once lived on the earth.The frozen physical remains of mammoths have been found in very cold, frozen regions. The frozen physical remains of mammoths are one kind of fossil.

Sometimes the physical remains of plants or animals are preserved in ice and snow, but sometimes the actual physical remains are preserved in amber. Amber, before it hardens, is a sticky substance called resin. Resin flows from certain trees and plants. Insects get caught in the resin. More resin falls on the insect and covers it completely. Later the resin hardens into amber, and the insect is perfectly preserved inside. Here is a picture of a piece of amber. Do you see the insect preserved inside the amber? Notice that the amber is a hard, yellowish brown substance.

Petrified traces of plants or animals are called fossils. Petrified means that the fossils have been turned to stone.

Probably the most common type of petrified fossil studied by paleontologists is a print fossil. A paleontologist is a scientist who studies fossils, which are actually the physical remains of a plant or animal or traces of past life. "Paleontologist” is the name for a scientist who studies all different kinds of fossils.

Sometimes a print fossil exists because a leaf left an impression, or print, in mud. Then the mud hardened and became stone. The impression of the leaf was left behind, although the leaf itself had decayed.

Another example of a print fossil is one which has the impression of a footprint. People and animals have left impressions of footprints in mud, which have later hardened into stone.

Some print fossils are molds where animal bodies once lay. These fossils were formed when mud covered the animals' bodies. Later, the bodies of the animals dissolved, but the impressions of the animals' bodies were left in the rock. Paleontologists can fill the molds with materials that harden into the shapes of the animals which once lay covered with mud.Paleontologists study all kinds of fossils. Fossils are the actual physical remains of plants or animals or petrified traces of plants or animals.

How Are Fossils Formed?

Some animals, such as mammoths, have been preserved in ice, and insects h preserved in resin hardened into amber.Most fossils were formed, however, after a plant or animal was buried under sediment. Sediment is material, such as stones, mud, and sand, which has bee along by water or wind. Whenever a load of sediment buried a creature, its were held together by sediment. After a while, the body decayed away and only parts (teeth, bones, shells) were preserved.Creationists (people who study science in the light of God's creation) agree Flood is the explanation for the fast forming of fossils. Usually there is little or no warning whenever a flood comes. Animals do not have time to escape. Floods carry sediment which buries the animals.

Sometimes the minerals of animal bones are leached. Leached means the mini the bones are washed away. Leaching has a peculiar effect on a bone fossil. L> leaves the bone fossil very light in weight. To prevent breaking a leached bon necessary to handle it very carefully. Petrified fossils are heavy, whereas leached are very light in weight.

"Fossilization'' is the word which describes what happens when things are quickly without having time to decay. In order for fossilization to take place, plants or animals must be buried quickly under sediment or something like volcanic ash fossils are found in sedimentary rock. Below is a picture of how fossilization car whenever an organism (a living thing) is trapped and buried in sediment.

     You have got the card with the task. We have just read the text and now let’s complete the sentences. (card #2)