Video Watching

Watch a video clip and answer the following questions. 

Notes

assembly[ə'sembli] 

    n. [C] a unit consisting of components that have been fitted together 集合 

furrow['fʌrəu] 

    n. [C] a long narrow cut in the ground, especially one made by a plough for planting seeds in 犁沟；沟 

plateau['plætəu]

    n. an area of flat land that is higher than the land around it 高原 

translucent[træns'lu:s(ə)nt] 

    adj. allowing light to pass through but not transparent 半透明的 

pore[pɔ:(r)] 

    n. [C] one of the very small holes in the skin毛孔 

perspire[pə'spaiə(r)] 

    vi. to produce sweat on the body 出汗；排汗 

magnify['mæɡnifai] 

    vt. to make sth look bigger than it really is 放大 

epidermis[,epi'də:mis] 

    n. [sing, U] (epi-, prefix on, over) the outer layer of the skin 表皮 

keratin['kerətin] 

    n. [U] a protein found in horny tissue 角蛋白 

waterproof['wɔ:təpru:f] 

    adj. that does not let water through 防水的 

lipid['lipid] 

    n. any of a class of organic compounds that are fatty acids or their derivatives that are insoluble in water but soluble in organic solvents 脂质

Script

 

Look,a bare hand. We sometimes lay our forehead on it when we feel tired. The envelope of the body, a living border between the inside and the outside, between thewet and the dry, the skin is an assembly of regular cells. It's covered with a network of furrow sand plateaus. The translucent spheres are drops of sweat which have reached the surface through pores. The skin thus evolves, breathes and perspires, getting rid of certain wastes of the body. This tormented landscape is our epidermis, magnified 150 times within it the layers of cells are in constant renewal. Cells are already dead when they reach the surface, disposed of and replaced by others produced in deeperlayers.

Here is a hair, magnified 180 times its root, invisible on the screen, loses itselfin the epidermis.A slight cut, this gray area at the center of the image, allows us to distinguish the various cell layers that constitute the epidermis. As we move deeper, we come across livingcells whose nucleus we can sometimes distinguish, those regular bubbles we can seeat the bottom of the screen. Above, flat cells, emptied of their content !constitute the upper layer of the epidermis. Within these, we find a very resistant protein, keratin , which can also be found in hair, and nails, and teeth. Here we are now at the heartof the epidermis.The membranes form a protective waterproof barrier. For this very purpose, they are joined together by something like a press stud, this dark crescent at thecenter ofthe image. Yet we can also see how they are arranged in lipid layers placedside by side1limiting exchanges with the outside. our microscope has unfortunately now reached its limits. Beyond this, nothing more is visiblefor the moment.