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Texts: the cell. Cells pre-reading and reading tasks.

1. Study the meaning and pronunciation of the following words:

arrange (v)

[q'reIndZ]

располагать в определённом порядке, ,

break down (v)

['breIk'daVn]

разрушить

damage (v)

['dxmIdZ]

повреждать

exhibit (v)

[Ig'zIbIt]

показывать, обнаруживать, проявлять

join (v)

[dZOIn]

соединяться; объединяться

pack up (v)

['pxk'Ap]

упаковывать

pertain (v)

[pq'teIn]

относиться, принадлежать; иметь отношение (к чему-л.)

store (v)

[stO:]

хранить, сохранять

twist (v)

[twIst]

скручивать, согнуть, сворачивать

vary (v)

['vFqrI]

отличаться, разниться

apparatus

["xpq'reItqs]

прибор, инструмент; аппарат

cilia

['sIlIq]

реснички

gene

[dZi:n]

ген

generalization

["dZen(q)rqlaI'zeIS(q)n]

обобщение

helix

['hi:lIks]

завиток

mucus

['mju:kqs]

слизь

tissue

['tISu:, 'tIsju:]

ткань

eucariotic

["ju: qkqrI'PtIk]

эукариотный

tiny

['taInI]

крошечный

proper

['prPpq]

надлежащий, должный, правильный

2. Make sure you know the following words and word combinations:

to vary in size

in total

naked eye

instruction manual

waste chemicals

double

3. Comment on the headline of the text before reading it. What do you know about the cell? Read the text and point out what information is new for you. The cell

A cell is the fundamental organizational unit of life. One of the most important generalizations of modern biology is the cell theory. There are two components of the cell theory. It states: (1) that all living things are composed of cells and (2) that all cells arise from other cells. Living things are chemical organizations of cells and capable of reproducing themselves.

There are many types of cells, and just as many classifications to go with them. There are plant cells, animal cells, eucaryotic cells, procaryotic cells, and many others. Also within each of these divisions, there are smaller subdivisions pertaining to the specific properties or functions of the cells. Cells exhibit considerable variation in properties based on different arrangements of components. Cells also vary in size, although most of them fall in the range of 5 to 20 m

In total there are about 50 billion cells in your body! Each cell is so small it cannot be seen with the naked eye. However, with the help of a microscope we are able to study cells and discover how they work.

Nearly all cells have a nucleus, which is the control center of the cell. Ribosomes in cells do as the nucleus tells them. They act like factories, making proteins and other chemicals for our body. To work properly a cell needs energy and this energy comes from the food we eat. Power stations in the cell, called mitochondria, change the energy stored in food into a form of energy that can be used by the cell.

We start life as one cell, which divides into two. These cells also divide, and as more cells grow they form different shapes and sizes. Each of these different types of cell has its own job to do. Similar types of cell will join together to make tissues, which form organs like our brain and lungs.

How long a cell lives depends upon the type of cell it is. Skin cells die quickly and are constantly replaced by new cells. Nerve cells should last a human lifetime and cannot be replaced even if they are damaged.

The control center of the cell is called the nucleus. Inside the nucleus of each cell lie tiny threads called chromosomes. Inside the chromosomes are smaller structures called genes. It is in the genes that the instruction manual lies. The instructions are in the form of a chemical called DNA. DNA is shaped like a twisted ladder, known as a double helix.

Ribosomes make proteins, as instructed by the nucleus. The golgi apparatus packs up the proteins made by ribosomes, ready to be stored or transported. Lysosomes help break down substances in the cell. The cell membrane allows food in the form of sugars to enter, and allows waste chemicals made in the cell pass out. Cilia are like tiny hairs that beat, pushing mucus or fluid over the cell surface. Inside a cilia there are 20 little tubes, arranged in pairs, to make it strong.