Unit 9 the nervous system

Vocabulary list to text a

anemone n	[əˈneməni]	анемона (морская)
appropriate adj	[əˈprəʊpriət]	соответствующий
cnidarians n pl	[naiˈderiənz]	книдарии
comb jelly n	[kəʊm] [ˈdʒeli]	гребневик
complexity n	[kəmˈpleksɪti]	сложность
cord n	[kɔːd]	хорда
ctenophores n pl	[ˈtenəˌfɔːz]	ктенофоры
diffuse adj	[dɪˈfjuːz]	диффузный
dilate v	[daɪˈleɪt]	расширяться
echinoderms n	[iˈkainəˌdɜːmz]	иглокожие
homeostasis n	[həʊmiəʊˈsteɪsɪs]	гомеостаз
hydra n	[ˈhaɪdrə]	гидра
intervention n	[ˌɪn.təˈvənʃən]	вмешательство
jellyfish n	[ˈdʒelifɪʃ]	медуза
limb n	[lɪm]	конечность
malfunction n	[mælˈfʌŋkʃən]	плохое функционирование
mezozoans n pl	[mezoˈzoʊən]	мезозой (животные)
multicellular adj	[mʌltiˈseljələr]	многоклеточный
peripheral adj	[pəˈrɪfərəl]	периферическая
pupil n	[ˈpjuːpl]	зрачок
radiate v	[ˈreɪdieɪt]	расходиться в виде лучей
spinal cord n	[ˈspaɪnəl kɔːd]	спинной мозг
sponge n	[spʌndʒ]	губка
vary v	[ˈveəri]	различаться
visceral adj	[ˈvɪsərəl]	висцеральный

Text a structure of the nervous system

 

The nervous system is the part of an animal's body that coordinates its behavior and transmits signals between different body areas. Its main functions are 1) to collect sensory information from the body and external environment; 2) to process and interpret all sensory information; 3) to create an appropriate response. The nervous system is made up of nervous tissues that are, in turn, made up of many types of neurons. There are billions of neurons connected throughout the animal’s body. These neurons are connected end to end and transmit electrical impulses from one point to another.   Nervous systems are found in almost all multicellular animals, but vary greatly in complexity. The only multicellular animals that have no nervous system at all are sponges and microscopic organisms called mesozoans. The nervous systems of ctenophores (comb jellies) and cnidarians (e.g., anemones, hydras, corals and jellyfishes) consist of a diffuse nerve net. All other types of animals, with the exception of echinoderms and a few types of worms, have a nervous system containing a brain, a central cord (or two cords running in parallel), and nerves radiating from the brain and central cord. The size of the nervous system can be from a few hundred cells in the simplest worms to 100 billion cells in humans.

In vertebrate animals, the nervous system consists of two main parts, called the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS contains the brain and spinal cord. Both the brain and the spinal cord are highly protected. The brain is protected by the skull and the spinal cord - by the vertebral bones. The brain is the largest part of the central nervous system. It regulates many different functions of the body. It processes all incoming information, and tells the body what to do in response. The spinal cord controls the flow of information to and from the brain.

The peripheral nervous system (PNS) is a collective term for the nervous system structures that do not lie within the CNS. It consists of nerves connected to the brain and the spinal cord. The peripheral nervous system has two types of neurons that are constantly at work. Neurons that send impulses from the central nervous system to limbs and organs are called motor (or: efferent) neurons. Neurons that receive sensory information and transmit it to the central nervous system are called sensory (or: afferent neurons). Therefore, as the stimulus is received, the sensory (afferent) neurons work and as reaction is needed, the motor (efferent) neurons go to work.

The PNS is divided into “somatic” and “visceral” parts. The somatic nervous system controls voluntary body movements such as walking, for example. It contains all the neurons that are connected with skeletal muscles and skin. The visceral nervous system, which is also known as the autonomic nervous system, controls internal body functions that are not under conscious control (heart and respiratory rates, digestion, etc). The autonomic nervous system has two subsystems with different functions – the sympathetic system and the parasympathetic system. They work opposite each other to maintain homeostasis.

The sympathetic system stimulates the “flight or fight”⃰ response that allows an animal to face up to an attacker or make a rapid departure. It increases the heart and respiratory rates, as well as the amount of blood flowing to the skeletal muscles while blood flow to less critical regions is reduced. It also causes the pupils of the eyes to dilate. In contrast to the sympathetic nervous system, the parasympathetic nervous system slows down the heart rate when the fight-or-flight response is no longer needed. It maintains the normal functions of the relaxed body, which are sometimes called the “housekeeping” functions. This part of nervous system promotes effective digestion, maintains a regular heartbeat and rate of breathing.

  Malfunction of the nervous system can occur as a result of genetic defects, physical damage due to trauma or toxicity, infection or simply of ageing. The medical specialty of neurology studies disorders of the nervous system and looks for interventions that can prevent or treat them.

*fight or flight – борьба или бегство Exercise 1. Complete the table a) on the parts of the nervous system b) and their functions.

Part of the nervous system	Function

Exercise 2. Look at the diagram above and speak on the structure of the nervous system.

Exercise 3. Complete the following sentences. Choose the ending according to the text. 1. The main functions of the nervous system are …  . 2. Nervous systems are found in almost all multicellular animals, but … . 3. The nervous systems of ctenophores (comb jellies) and cnidarians (e.g., anemones, hydras, corals and jellyfishes) consist of … . 4. In vertebrate animals the nervous system consists of two main parts, called … . 5. The central nervous system contains … . 6. The brain regulates … . 7. The spinal cord controls … . 8. The peripheral nervous system is divided into… . 9. The visceral nervous system, which is also known as the autonomic nervous system, controls … . 10. The autonomic nervous system has two subsystems with different functions – … .

Exercise 4. a) Make up collocations using words from both columns.

blood	information
multicellular	rate
spinal	defects
incoming	flow
respiratory	cord
genetic	animals

 

b) Fill in the gaps with the collocations from above.

1. Nervous systems are found in almost all …, but vary greatly in complexity. 2. The … controls the flow of information to and from the brain. 3. Malfunction of the nervous system can occur as a result of … , physical damage due to trauma or toxicity, infection or simply of ageing. 4. The sympathetic nervous system increases the heart rate and …, as well as the amount of blood flowing to the skeletal muscles while … to less critical regions is reduced. 5. The brain processes all …, and tells the body what to do in response.

Exercise 5. Translate the derivatives. Make up your own sentences with some of these words. 1. Nerve, nervous, nervously, nervousness. 2. To vary, various, variously, variety. 3. To protect, protection, protecting, protector. 4. To respond, responding, response, respondent.

Exercise 6. Give the English equivalents to the Russian words in brackets. 1. The nervous system is the part of an animal's body that (координировать поведение и передавать сигналы) between different body areas. 2. Its main functions are 1) to collect (сенсорная информация) from the body and external environment; 2) to process and (интерпретировать сенсорную информацию); 3) to create an (соответствующий ответ). 3. These neurons are connected end to end and (передавать электрические импульсы) from one point to another. 4. Nervous systems are found in almost all multicellular animals, but (сильно различаться по сложности). 5. In vertebrate animals the nervous system consists of two main parts, (называемых центральная нервная система и периферическая нервная система). 6. The somatic nervous system (контролировать сознательные движения тела). 7. The sympathetic nervous (вызывать расширение зрачка глаза). 8. The parasympathetic nervous system promotes effective digestion, maintains (регулярное сердцебиение и частоту дыхания).

Exercise 7. Translate into English.

1. Нервная система имеется у всех многоклеточных животных. 2. У позвоночных животных нервная система состоит из центральной нервной системы и периферической нервной системы. 3. Центральная нервная система включает в себя головной мозг и спинной мозг. 4. Головной мозг регулирует много разных функций тела, он перерабатывает всю входящую информацию и сообщает телу, что надо делать в ответ на входящую информацию. 5. Периферическая нервная система – это общий термин для всех структур нервной системы, которые лежат вне центральной нервной системы. 6. Периферическая нервная система состоит из нервов, соединенных с головным мозгом и спинным мозгом.

Exercise 8. The answers to the following questions are the summary of the text. Answer these questions and give the summary of the text.

1. What are the functions of the nervous system?

2. Of what tissues is the nervous system made up?

3. What are the animals that have no nervous system?

4. What are the main parts of the nervous system in vertebrates?

5. What is the function of the brain?

6. What does the spinal cord control?

7. What is the peripheral nervous system?

8. What are the two types of neurons of the peripheral nervous system?

9. What is somatic nervous system responsible for?

10. What are the two subsystems of the autonomic nervous system?

11. What are the functions of the somatic nervous system?

12. What does parasympathetic system control?

13. Why does malfunction of the nervous system occur?

14. What branch of medicine studies malfunction of the nervous system?