HBS Unit 3.4 Test

Normal H2O levels with more ADH

1. Less H2O in the blood 2. Detected by osmoreceptors in the hypothalamus 3. Signals thirst by telling the pituitary to release more ADH 4. Signals the nephron to reabsorb more H2O, decreasing urine production.

Normal H2O levels with less ADH

1. More H2O in the blood 2. Detected by osmoreceptors in the hypothalamus 3. Signals the pituitary to release less ADH 4. Signals the nephron in the kidney to reabsorb less water, creating more urine.

Ureter

A duct leading from the kidney to the urinary bladder.

Explain how a shortage of water affects the health of your cells. Make sure to use words such as osmosis, hypertonic solution, hypotonic solution, or isotonic solution in your answer.

A shortage of water will cause your cells to be hypotonic, meaning that there is more water inside the cells than outside because you are losing water due to either urinating, dehydration, or sweating. The water will move from an area of higher concentration to a lower concentration through a process called osmosis. This process will occur until the cells are isotonic, meaning that the concentration of water both inside and outside of the cells are the same. If there is not enough water in the cell, it will die.

Urethra

A tube that releases urine from the body near the vagina in females or through the penis in males; also serves in males as the exit tube for the reproductive system.

Why did Bill keep running to the bathroom?

Alcohol reduces the ADH hormone production which will cause the kidneys to flush water rather than absorbing it.

What is the purpose of aldosterone?

Aldosterone is the hormone produced by the adrenal glands above the kidneys and plays a central role in regulating the blood pressure by increasing the amount of sodium reabsorbed in the bloodstream to increase the amount of potassium excreted in urine. It also increases the amount of water reabsorbed which increases the blood volume, thus increasing blood pressure.

Which parts of the nephron does aldosterone act on?

Aldosterone mainly acts on the distal convoluted tubule and collecting duct of the nephron to directly impact the sodium reabsorption and potassium excretion, as well as hydrogen ion excretion.

How did the events of Bill's day impact his body's ability to conserve and balance water?

Bill is dehydrated because alcohol suppresses the ADH hormone causing the body to become unbalanced so his body continues to excrete more water making him even more dehydrated.

Would blood ADH levels be higher or lower than normal in a person who just completed a three-mile run without drinking any water? Explain.

Blood ADH levels would be higher than normal in a person who ran three miles because antidiuretic hormone works to conserve water within the body. A diuretic is something that increases urine formation, thus an ANTIdiuretic does the opposite. Since the person just ran three miles, they sweated a lot more water out of their system, therefore they need more water in their body.

Explain why diagnostic tests are classified as a type of medical intervention.

Diagnostic tests are classified as a medical intervention because they were created in order to test individuals and treat or create preventative measures for the patient.

Explain how drinking too much water can throw off the electrolyte balance in your blood. How does this imbalance specifically affect the nervous system and the muscular system?

Drinking too much water can throw off the electrolyte balance in your blood because it can dilute the electrolyte. Electrolytes like sodium and potassium play an important role in the body for not only water conservation, but nerve signals as well (sodium-potassium pump). Without a sufficient concentration of sodium and potassium, a neuron cannot conduct its signal properly.

Urinalysis is an important diagnostic tool for the determination of medical disorders. However, urinalysis has many other uses. Describe one other reason a person may have his/her urine tested.

Drug testing for a school sport or job.

T or F: The kidneys are found on the anterior wall of the kidney

False

Where does the most reabsorption take place in the nephron?

Most of the fluid is reabsorbed by the p.c.t. and the descending limb of the loop of henle

Is the ADH feedback loop an example of positive or negative feedback? Explain.

Negative feedback because it involves trying to conserve water resulting in increased blood pressure and volume when they are too low.

Urine is produced by the

Nephron

How will other body systems be affected if the kidneys begin to shut down? Explain your answer.

Normally, kidneys work with the cardiovascular system to control blood pressure. Everytime blood pressure falls too low, an enzyme called renin is released by the kidneys. Renin signals the liver to make a hormone called angiotensin in order to tell the blood vessels to constrict, elevating blood pressure. However, an overactive renin-angiotensin system can lead to problems. Cells may grow to quickly or too slowly causing inflammation, hardening of the arteries, and/or blood clots. In essence, if your kidneys shut down you blood pressure becomes uncontrollable.

Kidney

One of a pair of vertebrate organs situated in the body cavity near the spinal column that excrete waste products of metabolism, in humans are bean-shaped organs about 4½ inches (11½ centimeters) long lying behind the peritoneum in a mass of fatty tissue, and consist chiefly of nephrons by which urine is secreted, collected, and discharged into the pelvis of the kidney whence it is conveyed by the ureter to the bladder.

The kidneys are supplied blood by which arteries?

Renal arteries

Which muscles are voluntary muscles at the end of the urethra that controls whether or not urine is released?

Sphincter muscles

Explain the role of the digestive system, the respiratory system and the urinary system in the removal of waste. How do these waste products relate to the three core resources?

The large intestine absorbs water from the remaining product of digestion and excretes the waste material from the body. Within the urinary system the kidneys are able to filter out and reabsorb products such as glucose and electrolytes, while letting waste products such as salts, ammonia, some amino acids, and by products of bile to be excreted from the body in the form of urine. Feces is made by the processes of digestion, and urine is principally made of water. Carbon dioxide is a waste byproduct of cellular respiration in our bodies that is fueled by the oxygen we breathe in.

Explain how both the digestive system and the urinary system work to conserve water in the human body.

The large intestine within the digestive system conserves water by excreting it as waste or keeping it when it is needed. The urinary system controls the amount of salt and water balance in the blood through aldosterone.

If you stretched the nephrons in a kidney from end to end, they would be over 40 miles long! Explain how this structure directly relates to the function of the kidney.

The nephron is the functional unit of the kidney that works to filter, reabsorb, and secrete nutrients throughout the body to create urine.

Urinary System

The organs of the urinary tract comprising the kidneys, ureters, urinary bladder, and urethra.

What organs or structures in the body (other than the urinary system) help you maintain a water balance?

The pituitary gland helps maintain water balance by controlling the amount of ADH and aldosterone secreted. When the body is low in water the pituitary secretes more ADH into the bloodstream. The circulatory system also maintains water balance because without it, the hormones wouldn't be able to get to the other structures of the body.

Urinary Bladder

The pouch where urine is stored prior to elimination.

Where does the most GLUCOSE reabsorption occur in the nephron?

The proximal convoluted tubule

What is the overall purpose of ADH?

The purpose of ADH is to control how much urine is produced in the nephron.

What is the purpose of reabsorption in the nephron?

The purpose of reabsorption in the nephron is to return the nutrients we need to survive back into the blood.

In what direction are substances moving during the process of secretion? Explain what these substances are and why they are excreted from the body.

The substances move in the direction from the bloodstream to the tubules, however that is opposite of the direction reabsorption takes place. These substances include potassium ions, creatinine, NH4+, hydrogen ions, urea, hormones, and some drugs. It's important for these to leave the body because they are considered toxic to the body if there is too much.

Bladder is made up of what kind of tissue?

Transitional epithelium

Urine

Waste material that is secreted by the kidney, is rich in end products (as urea, uric acid, and creatinine) of protein metabolism together with salts and pigments, and forms a clear amber and usually slightly acid fluid.

What is happening to his body since he is producing so much urine?

With low ADH levels Bill's bladder is filling up quickly and he is becoming dehydrated.