Answer the questions. 1What are the characteristics of the mechanisms of fever?

1 What are the characteristics of the mechanisms of fever?

2 In what way is limitation of heat emission realized?

3 What does the decrease in skin temperature result in?

4 What is the spinal oscillator responsible for?

5 Why are contractile and non-contractile thermogeneses increased?

6 How long does the first stage of fever last?

7 What does stadium fastigii, or acme, signify?

8 What is the heat production and heat emission relationship like at stadium fastigii?

9 What does stadium decrementi result from?

10 What is the relationship between heat production and heat emission at stadium decrementi?

11 What can complicate abrupt enlargement of blood vessels in the case of critical temperature fall?

12 What is the effect ofrepeated injections of exogenous pyrogens and of endogenous pyrogens?

13 What is the difference betweenhyperthermia andfever?

6Complete the following sentences using an appropriate verb from the box.

Heat emission heat production temporary mechanisms thermogenesis vasoconstriction afferent spinal extensors stadium incrementi coefficient set-point constant homeostasis collapse pyrogen latent injection Indian ink hyperthermia dehydration hypoxia

1 Feveris characterized by the limitation of ………. with the simultaneous intensification of ………..

2 Hyperthermia, unlike fever, is a ………. increase of body temperature due to the disturbance of thermoregulatory ………. and brake-down of balance between ………. and heat emission (evolution).

3 Limitation of heat emission is realized by sympathetic ………. of skin blood vessels.

4 The ………. signalization of cold thermo receptors and shivering result from the decrease in skin temperature.

5 The ………. oscillator is responsible for the shivering reflex (simultaneous contraction of flexors and ……….).

6 The first stage of fever is ………., characterized by increasing temperature lasts, from 3 to 4 hours.

7 At the first stage of fever the respiratory ………. increases up to 1.0.

8 A new ………. of temperature homeostasis is reached at the stage of ………. temperature.

9 The stage of temperature decrease results from the recourse of the set-point of temperature ………. down to the normal level.

10 In case of critical temperature fall abrupt enlargement of blood vessels may be complicated by ………..

11 The onset of fever in response to ………. injection begins after a certain ………. period.

12 The latent period depends on the nature and potency of pyrogen, and the way of ………..

13 The blockade of the system of mononuclear phagocytes with ………. prevents the development of fever after introduction of exogenous pyrogens.

14 At ………. the ability of the organism to emit heat is lower than heat production.

15 Hyperthermia results in ………., circulatory disorders and ………..

7Complete the conversation with the words from the box.

homeostasis shivering skin sympathetic (x 2) hypoxia heat loss potency exogenous dehydration flexors activation adrenal medulla sympathetic injection latent collapse vagal exceeds endogenous

Examiner: Let’sdiscuss the fever in adults as well as experimental fever and hyperthermia. To begin with, how do fever and hyperthermia differ?

Student: Well, feveris characterized by the limitation of 1 ………. with the simultaneous intensification of heat production while hyperthermiais a temporary increase of body temperature due to the disturbance of thermoregulatory mechanisms and brake-down of brake-down of the balance between thermogenesis and heat emission. Examiner: What does hyperthermia result in?

Student: Hyperthermia results in 2 ………., circulatory disorders and 3 ……….. Fever does not produce any of the aforementioned consequences.

Examiner: What is thelimitation of heat emission realized by?

Student: It’s realized by means of 4 ………. vasoconstriction of skin

blood vessels.

Examiner: What do the afferent signalization of cold thermo receptors and shivering result from?

Student: They result from the decrease in 5 ………. temperature.

Examiner: What is the spinal oscillator responsible for?

Student: It is responsible for the 6 ………. reflex, that is simultaneous contraction of 7 ………. and extensors.

Examiner: Why are contractile and non-contractile thermogeneses are increased?

Student: They’re increased on account of 8 ………. reflexes and stimulation of the 9 ………. and, further, on account of the 10 ………. of the hypothalamus ––hypophisis–thyroid axis.

Examiner: What does the stage of constant temperature signify?

Student: This stage is the evidence of a new set-point of temperature 11 ………. having been reached.

Examiner: What does the stage of temperature decrease result from?

Student: This stage results from the recourse of the set-point of temperature homeostasis down to the normal level after the 12 ………. pyrogens have been exhausted, while the 13 ………. ones are no longer formed.

Examiner: And what is the balance of heat loss and heat production at this stage?

Student: Heat emission 14 ………. heat production.

Examiner: OK. What can happen in the case of quick temperature fall?

Student: In this caseabrupt enlargement of blood vessels, or 15 ………. enlargement, may be complicated by 16 ………..

Examiner: When does the onset of fever in response to pyrogen injection occur?

Student: It begins after a certain 17 ………. period whose duration is shorter in the case of an endogenous pyrogen 18 ………..

Examiner: And, finally, what does the length of the latent period depend on?

Student: In depends on the nature and 19 ………. of a pyrogen, and the way of injection.