Exercise 24. Give the definition of the following words.

Magnetic Resonance Imaging, ultrasound, cytology,fecal test,a pathologist, an electrocardiogram,intravenous pyelogram,ectoparasites,complete blood count, a biopsy, a myelogram,necropsy, skin scraping,saline, anemia, biochemistry panel.

Exercise25.TranslatethefollowingwordsandphrasesintoEnglish.

Установленный порядок обследования,относительно новый метод диагностики, соответствующие этиологические данные, точная лабораторная диагностика, окончательная идентификация, сбор информации о животном, значительно улучшить, увеличение числа эритроцитов,функционированиевнутреннихорганов (организма), стерильныйсолевойраствор, прямоймазок (безпоследующегопосева), проникатьвверхниеслоикожи, красящее вещество, взять биопсию,ушной клещ, магнитное поле.

Exercise 26.Agree or disagree with the statements.

1.Accurate laboratory diagnosis should be obtained in order to make conclusive identification of a disease. 2. Adequate etiological evidence can be of some importance only in case of infectious diseases. 3. Treatment and prevention of disease are the first steps in the disease recognition process. 4.Urinalysis is a measure of an animal’s white blood cells (WBC’s) and red blood cells (RBC’s). 5. Fecal test is aimed at the egg of the parasite, not the actual parasite. 6. Since parasites live only on the surface of the skin,the scraping is never done deep. 7.The electrocardiogram can help diagnose a heart that is having a problem but appears normal during a physical exam. 8. Cytology is one of the most crucial steps to determine what the lesion is, and whether it is benign or malignant.9. Both radiology and ultrasound allow to biopsy the inner organs using a small biopsy needle.10. MRI is particularly useful in neurologic diseases and for the diagnosis of problems in the brain.

Exercise 27. What diagnostic tests are the most common for:

- kidney diseases;

- heart diseases;

- anemia;

- disorders of the intestine;

- lung diseases;

- inflammation of skin;

- traumas;

- neoplasms;

- persistent fistula;

- coordination disorders.

Exercise 28. Studythe plans outlined below. What are the benefits of adopting them? Do you agree that they were developed for your pet to receive a broad range of services?Is it an important step in managing your pet's health? Do you think these plans provide your pet with the preventive care services? Do these plans assist tomonitor and treat conditions?

 

 

Canine Annual Wellness Plans

 

FelineAnnualWellnessPlans

 

UNIT 2

VIRUSES

TEXT A

VIRUSES –SUBMICROSCOPIC PARASITES OF PLANTS,

ANIMALS AND BACTERIA

 

VOCABULARY LIST TO TEXT A

adsorption n	[ædˈsɔːpʃn]	адсорбция, прикрепление
assembly n	[əˈsembli]	синтез
bacteriophage n	[bækˈtɪərɪə(ʊ)feɪdʒ]	бактериофаг
capsid n	[ˈkæpsɪd]	капсид (белковая оболочка вируса)
capsomer n	[ˈkæpsəmə]	капсомер(структурная единица капсида)
cell-preference n	[sel ˈpref(ə)r(ə)ns]	клеточная специфичность
core n	[ˈk ɔː]	сердцевина
deoxyribonucleic adj	[diˌɒksiˌraɪbəʊnjuːkleɪɪk]	деоксирибонуклеиновый
DNA virus	[ˈdiːˈenˈeɪˈvaɪrəs]	дезоксивирус
double stranded	[ˈdablstrændɪd]	двуцепочечный
entry n	[ˈentrɪ]	проникновение
helical adj	[ˈhelɪk(ə)l]	спиральный
genome n	[ˈdʒiːnəʊm]	геном, совокупность генов
icosahedral adj	[ˌaɪkəsəˈhiːdrəl]	кубический, икосаэдральный
latent adj	[ˈleɪt(ə)nt]	латентный, скрытый
lytic cycle	[ˈlitiksaɪkl]	литический цикл
machinery n	[məˈʃiːn(ə)rɪ]	механизм
naked virus	[ˈneɪkɪd]	“раздетый” вирус
nanometer n	[ˈnænəˌmiːtə]	нанометр
nucleocapsid n	[ˈnjuːˌkləʊˈkæpsɪd]	нуклеокапсид
receptor n	[rɪˈseptə]	рецептор
release n	[rɪˈliːs]	освобождение
replication n	[replɪˈkeɪʃ(ə)n]	репликация
ribonucleic adj	[ˌraɪbəʊnjuːkliːɪk]	рибонуклеиновый
RNA virus	[aː(r)ˈeneɪˈvaɪrəs]	рибовирус
rota virus	[ˈrəʊtəˈvaɪrəs]	ротовирус
single stranded	[ˈsɪŋɡ(ə)lstrændɪd]	одноцепочечный
spiky adj	[ˈspaɪki]	покрытый шипами
take over v	[ˈteɪkˈəʊvə]	здесь: перестроить
virion n	[ˈvaɪrɪən]	вирион

 

A virus is an infectiousagent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. They range in size from about 20 to 400 nanometres in diameter (1 nanometre = 10^-9 meters).The virus particles are 100 times smaller than a single bacteria cell. A virus particle (virion) has two main parts:

- A nucleic acid genome –the core of the virus with the DNA or RNA (deoxyribonucleic acid and ribonucleic acid respectively). The DNA or RNA holds all of the information for the virus.

- Protein Coat (capsid) –covering over the nucleic acid that protects it. It may contain enzymesthat enable the virus to enter its appropriate hostcell. Capsid has a symmetrical structure and is built of one or more subunits packed like a chemical crystal. A structural unit consisting of the genetic material of a virus and the protein thatsurrounds it is called a nucleocapsid.

Sometimes the capsid is surrounded by an additional spiky coat called the envelope (lipid membrane). Many viruses do not have this envelope and are called naked viruses. This coat enables the virus to survive outside the cell sufficiently long to spread elsewhere via the blood.

Viruses by themselves are not alive. They cannot grow or multiply on their own and need to entera human or animal cell and take over the cell to help them multiply. The virus particles or the virions attack the cell and take over its machinery to carry out their own life processes of multiplication and growth. Viruses are not simply taken into cells, they must first attach to a receptor on the cell surface. Each virus has its specific receptor. It is the distribution of these receptor molecules on host cells that determines the cell-preference of viruses. For example, the cold and flu virus prefers the mucus lining cells of the lungs and the airways.

There are a few basic steps that all viruses follow and these are called the lytic cycle. These include:

1. A virus particle attaches to a host cell. This is called the process of adsorption.

2. Entry is the process when the virus particle injects its DNA or RNA into the host cell.

3. The cellular enzymes start making new virus particles. This process is called replication.

4. The particles of the virus created by the cell come together to form new viruses. This is called assembly.

5. The newly formed viruses kill the cell so that they may break free and search for a new host cell. This is called release.

The infected cell usually dies because the virus keeps it from performing its normal functions. Before it dies, however, the cell has already released new viruses, which go on to infect other cells. Some viruses do not kill the cells they infect, but instead change the cells’ functions. Sometimes, the infected cell loses control over normal cell division and cancer cells are produced. Some viruses that do not kill the cells they infect leave their genetic material in the host cell, where it can remain inactive for a long time. This is called a latent infection. When the cell is disturbed, the virus may begin to replicate and cause disease.

Viruses are transmitted in a variety of ways, depending on the body system affected. For example, common viruses of the respiratory tract are usually inhaled, and viruses of the digestive tract are often swallowed. Other viral infections are transmitted by the bites of insects and other parasites (such as mosquitoes and ticks). Most viruses infect only one or a few species. For example, canine parainfluenza virus does not infect people. Feline leukemia virus does not infect dogs. Rabies is an exception and can affect any mammal.

The body has a number of defences against viruses. Physical barriers, such as the skin, prevent easy entry. When a virus enters the body, it triggers the body’s immune defences. These defences begin with white blood cells, such as lymphocytes, which attack and destroy the virus or the cells it has infected. If the body survives the viral infection, the lymphocytes “remember” the invader and can respond more quickly and effectively to a later infection with the same virus. This is the basis of immunity.

All viruses can be divided into two groups based on their nucleic acid: DNA viruses and RNA viruses. The genomes of viruses can be comprised of single or double stranded DNA or RNA.

A capsid is almost always made up of repeating structural subunits that are arranged in one of three symmetrical structures: helical, icosahedral or complex.

1. Helical structures. There is a capsomer (a morphological unit of the capsid of a virus) coiled around a central axis to form a helical structure. This is a common structure seen in single stranded RNA viruses.

2. Icosahedral structures. In these structures, the subunits are arranged in the form of a hollow, quasi spherical structure, with the genome within. Rota virus has twelve capsomers and is spherical.

 

3. Complex structures. There is a capsid that is neither purely helical, nor purely icosahedral. There may be extra features like protein tails or a complex outer wall. Bacteriophages are examples of this type of viral structure.

Bacteriophages, also known as phages, are viruses that infect bacteria.Bacterial viruses are specific to one or a limited number of bacteria; thus, they are named after the bacteria group, strain, or species that they infect. For example, the phages that infect the bacterium Escherichia coli are called coliphages.

 

TRICKY WORDS