Hormone Control of Water and Salt

Water reabsorption is controlled by the antidiuretic hormone (ADH) in negative feedback. ADH is released from the pituitary gland in the brain. Dropping levels of fluid in the blood signal the hypothalamus to cause the pituitary to release ADH into the blood. ADH acts to increase water absorption in the kidneys. This puts more water back in the blood, increasing the concentration of the urine. When too much fluid has accumulated in the blood, sensors in the heart signal the hypothalamus to cause a reduction of the amounts of ADH in the blood. This increases the amount of water absorbed by the kidneys, producing large quantities of a more dilute urine.

Aldosterone, a hormone secreted by the kidneys, regulates the transfer of sodium from the nephron to the blood. When sodium levels in the blood fall, aldosterone is released into the blood, causing more sodium to pass from the nephron to the blood. This causes water to flow into the blood by osmosis. Renin is released into the blood to control aldosterone.

If kidneys are diseased and not working properly, the accumulation of waste in the system will eventually results in death. Infection, environmental toxins such as mercury, and genetic disease can have devastating results by causing disruption of kidney function. Some kidney diseases can be treated with medication. Severe kidney diseases require more intense treatment. Many kidney problems can be treated by dialysis, where a machine acts as a kidney. The patient should have his (her) blood pumped through a dialysis machine which filters the waste from the blood and returns the clean blood. A dialysis patient has to spend nearly sixty hours each week attached to the machine.

Kidney transplants are an alternative to dialysis. The most radical treatment for kidney disease is a kidney transplant. Healthy people can live comfortably with only one kidney. Therefore, their other kidney can be donated to a person with kidney disease. The donor and patient must have very similar genetic structures in order for the patient to accept the new kidney without complications. The patient also receives anti-rejection drugs. During a kidney transplant operation, the healthy kidney is placed in the abdomen of the patient and attached to the blood vessels and bladder. The patient's original kidneys are not removed.

Kidney Stones

In some cases, excess wastes crystallize as kidney stones. They grow and can become a painful irritant that may require surgery or ultrasound treatments. Some stones are small enough to be forced into the urethra, others are the size of huge, massive boulders.

 

XIV.Mix and match:

1. uric acid a)antidiuretic hormone which reduces the

2. urea rate of urine output

3. urine is b)a substance derived from creatineand

4. creatinine creatine phosphate in muscle

5. renin c)a nitrogen-containing organic acid

6. vasopressin that is the end-product of nucleic acid

Metabolism

d) an enzyme released from the blood by the

Kidney in response to stress

E) the main breakdown product of protein

Metabolism

F) the fluid excreted by the kidneys, which

contains many of body`s waste products

XV. Make the sentences complete:

Urethra

1. Urethra is the tube that …… a) longer (about 20 cm) and runs through

the penis.

2. The female urethra is …… b) urethritis.

3. The male urethra is …… c) conducts urine from the bladder to the

exterior.

4. Urethra, as well as urine, receives …… d) by administration of appropriate

antibiotics.

5. The inflammation of the urethra e) quite short (about 3.5 cm).

is called ……

6. The treatment of urethritis due to f) the secretion of male accessory sex

infection is …… glands and spermatozoa.

 

 

XVI. Rearrange the sentences in correct order:

 

Ureter

 

5. Ureteritis is an inflammation of the ureter which usually occurs in association with inflammation of the bladder.

6. They conduct urine from the pelvis of the kidneys to the bladder.

7. Smooth muscles contract to force urine into the bladder.

8. Ureter is either of a pair of tubes, 25-30 cm long.

9. The walls of the ureters contain thick layers of smooth muscle between an outer fibrous coat and an inner mucous layer.

 

XVII.!Запомните правило

Emphatic Construction

 

В английском языке существует усилительная конструкция – It is (was) …… that (who), которая служит для выделения членов предложения. Эта конструкция может употребляться только в настоящем и прошедшем времени, и стоит всегда только в единственном числе, хотя слова, которые выделяются при помощи конструкции могут быть как в ед. так и во мн. числе.

На русский язык она переводится словом именно.

 

e.g. It is in the alveoli that the respiratory metabolism takes place. – Именно в альвеолах происходит дыхательный метаболизм.

 

e.g. It was Alexander Fleming who discovered penicillin in 1942. – Именно Александр Флеминг открыл пенициллин в 1942 году.

 

N.B. Обратите внимание на тот факт, что при выделении неодушевленных предметов в составе конструкции используется слово - that, а при выделении людей – who.

 

Read and translate the sentences incorporating Emphatic Construction:

 

1. It was Sechenov who investigated blood gases.

2. It is hemoglobin that carries oxygen to different tissues of the human body.

3. It is uric acid that is the component of the urine.

4. It is the accumulation of urea in the bloodstream together with other nitrogenous compounds that results in uraemia.

5. It was at our chemist`s that I bought these drugs to relieve bladder spasms.

6. It was urologist in our local polyclinic who prescribed me Monurol for the treatment of uncomplicated urinary infection.

7. It is sodium chloride that is another major constituent of urine.

 

 

XVIII.Read the text “Bladder” and find the sentences incorporating Emphatic Construction:

Bladder

Bladder is a sac-shaped organ that has a wall of smooth muscle. It is bladder that stores the urine produced by the kidneys. Urine passes into the bladder through the ureters. The release of urine from the bladder is controlled by a sphincter at its junction with the urethra. It is the bladder neck that is the outlet of the bladder where it joins the urethra. In males it is in contact with the prostate gland. Bladder is under the control of the autonomic nerves of the pelvis. It is the neck of the bladder that is the commonest site for the retention of urine.

Inflammation of the urinary bladder is called cystitis. Most commonly it is the bacterium Escherichia coli that causes this inflammation. An acute attack of cystitis is treated by antibiotic administration and a copious ([`koupj s] – обильный) fluid intake.

 

XIX.Substitute English words for the Russian ones:

 

Kidney

 

Kidney is either of the пара of organs responsible for the выделение of азотистых wastes, principally моча, from the blood. The kidneys are situated at the back of the брюшная полость, below the диафрагма, one each side of the позвоночник. Kidneys are supplied with blood by the почечные arteries. Each kidney is enclosed in a волокнистая capsule and is composed of an outer кора and внутренняя medulla. The active единица of the kidney is the нефрон within the cortex and medulla. The nephrons filter the blood under давление and then reabsorb water and selected вещества back into the blood. The urine thus сформированная is conducted from the nephrons через the renal трубочки into the renal pelvis and from here to the мочеточник, which leads to the мочевой пузырь.

 

Quiz:

Excretory System

 

1. Excretion is the removal of the metabolic wastes of an organism. These wastes must
have travelled at one time in the:

A. lungs

B. blood
C. rectum

2. The excretory system consists of:
A. rectum, lungs, skin and kidneys
B. rectum, liver and kidneys

C. lungs, liver, skin and kidneys

3. The wastes excreted from the lungs are:
A. carbon dioxide and excess oxygen

B. carbon dioxide and nitrogen

C. water and carbon dioxide

4. The role of the liver in excretion is the production of urea from:
A. ammonia

B. uric acid

C. fatty acids

5. Examples of nitrogenous wastes are:
A. fatty acids and glycerol

B. water and carbon dioxide

C. urea and uric acid

6. Sweat contains:

A. water, excess salt and ammonia

B. excess water, excess salt, urea and uric acid

C. excess water and salt only

7. The outer layer of the skin is the:
A. epiglottis

B. dermis

C. epidermis

8. The organs responsible for filtering the blood arethe:
A. kidneys

B. intestines

C. rectum

9. Approximately how much blood is filtered every day?
A. 150 to 200 litres

B. 2 to 3 litres

C. 1 litre

10. What name is given to the millions of tiny filtering units that make up each kidney?

A. nephrons

B. tubules

C. filter organs

11. The tube between the kidney and the urinary bladder is the:
A. renal vein

B. urethra

C. ureter

12. The tube that carries urine from the bladder to the outside of the body is the
A. renal vein

B. urethra

C. ureter

13. What is the name of the circular muscle that controls the flow of urine from the body?
A. bladder muscle

B. kidney muscle

C. sphincter muscle

14. 'Body balance' of temperature and water salt and glucose levels is correctly termed:
A. peristalsis

B. homeostasis

C. endometriosis

15. Examples of how the body maintains a constant body temperature are:
A. sweating and urination

B. salt and fibre excretion

C. “goosebumps and glucose excretion

 

Read the text concerning the effect of taking drugs on the renal system; make the summary of the text in Russian:

Drug history

 

Renal failure has important effects on drug metabolism and pharmacokinetics, and drugs may damage the kidneys. Examples of drugs which accumulate in renal failure are digoxin, lithium, aminoglycosides, opioid analgesics and water-soluble beta-blockers such as atenolol.

A wide range of drugs may alter renal function, or cause renal failure, including angiotensin-converting enzyme Inhibitors, angiotensin receptor antagonists and non­-steroidal anti-inflammatory drugs. These drugs have no adverse effect on normal kidneys, but reduce glomerular filtration when the kidneys are underperfused. Non-steroidal anti-inflammatory drugs, in particular, can dramatically reduce renal function in the presence of systemic infection or hypovolaemia. They are commonly taken as over-the-counter drugs so it is always necessary to ask about their usage.

Other drugs are toxic even to the normal kidneys. Examples include aminoglycosides, amphotericin, lithium, ciclosporin and tacrolimus, and in overdose, paracetamol.

Some drugs cause renal failure by indirect mechanisms. An example is rhabdomyolysis and myoglobinuric acute renal failure occurring in intravenous drug and cocaine users.

 

Render from Russian into English:

Мочевыделительная система

Мочевыделительная система у человека представлена почками, мочеточниками, мочевым пузырём и мочеиспускательными каналами.

Почки - это парный орган. Они имеют бобовидную форму и гладкую ярко-коричневую поверхность. Вес каждой почки у взрослого человека колеблется от120гр. до 200гр., длина 10-12см., ширина 5-6 см., толщина 3-4 см. Почки расположены в поясничной области по обе стороны от позвоночника. Они окружены жировой клетчаткой (волокнистой) и соединительной тканью.

В почке есть крупные артерии и вена, лимфатические сосуды, нервные волокна.

Почка- это система однотипных по строению образований, называемых нефрона. Каждый из них является отдельной функциональной единицей.

Почки, будучи экскреторным органом, выводят из организма продукты азотистого обмена - мочевину, креатинин, мочевую кислоту и др., избыток солей и воды, а также различные чужеродные вещества. Но эта функция у почек не основная. Главное в работе почек - это регуляция водного и электролитного обмена, чтобы поддерживать важнейшие параметры организма: объём и осмотическое давление крови и жидкостей