Chapter 12 - Execratory System

Question 1

How/Where/Why is urea formed?

Answer 1

When there is an excess amount of proteins, they will turn into carbohydrates. In this process, proteins release a Nitrogen group. This nitrogen group turns into ammonia, and this compound is toxic. SO from there, ammonia links with a CO2 to create urea. This process happens in the liver and is called Deamination

Question 2

How is Uric Acid formed?

Answer 2

Nucleic acid is turned into Uric Acid

Question 3

How do we know when to pee?

Answer 3

Stretch receptors exist on the outside of the bladder which indicate to our brain that we need to go.

Question 4

What three things happen to form urine?

Answer 4

Glomerular filtration
Tubular Reabsorption
Tubular secretion

Question 5

What happens in glomerular filtration?

Answer 5

The Bowman’s capsule takes things from the glomerulus and will filter out things too large to go through, such as proteins, RBC’s, etc.

Question 6

What does filtrate consist of?

Answer 6

Water, Salts, Urea, Amino Acids, Glucose, Hormones

Question 7

What happens in tubular reabsorption?

Answer 7

Only 1mL of FIltrate out of 120 mL is not absorbed. Absoprtion happens when the aldosterone hormone is released,increasing permeability of the Nephron and allowing salts to flow out and into the capilaries. Water follows the salts out, as well as oppositely charged ions

Question 8

How does active transport work in the Nephron?

Answer 8

Molecules like Na+ will be taken through the cell membrane by carrier proteins. Oppositely charged ions will follow the Na+ and exit the Nephron as well.

Question 9

What is threshold level?

Answer 9

The level at which our blood does not allow anymore certain molecules to be reabsorbed. This is done to conserve energy. Unabsorbed molecules will stay in the filtrate and exit in the urine

Question 10

How does tubular secretion work?

Answer 10

Wastes from the blood are actively transported to the Nephron, supported by ATP from the mitochondria that exist on the outside of the Distal Tubule.

Question 11

How does the Kidney keep pH neutral?

Answer 11

The kidney creates HCO3- by taking CO2 ions from cellular respiration and linking it with H2O, creating H2CO3, from there, an H+ ion is taken out and the HCO3- is formed, leaving the kidney with a Na+ ion. This is because during cellular respiration, H+ ions are created. These ions are acidic, so HCO3- is made (a base) to neutralize the H+)

Question 12

How does the kidney help Water Balance?

Answer 12

By creating and letting out certain hormones like Aldosterone, Renin, and ADH

Question 13

How does Aldosterone work?

Answer 13

Aldosterone is released when there is a low Blood Sodium Level detected. The permeability of the Nephron will increase and allow for more Salts to leave the Nephron. When salts enter the blood, this will increase the blood pressure. Water will follow as well.

Question 14

What is Addisons Disease?

Answer 14

The lack of Aldosterone. Salt will stay in the urine, and not the blood

Question 15

What does Renin do?

Answer 15

Renin is released when there is low blood pressure. Renin activates Angiotensin, and this will release Aldosterone. Angiotensin causes Vasoconstriction, which increases blood pressure, and Aldosterone will also cause an increase in blood pressure. (More salt in blood = Higher BP)

Question 16

What does ADH do?

Answer 16

Activated when there is osmoregulairty. Does the opposite of Aldosterone. Will cause an increase in the reabsorption of water in the blood. This will dilure the blood and fix it if the blood is too salty, for example

Question 17

How are Kidney stones created?

Answer 17

When there is a larger amount of crystallizing minerals in your urine.

Question 18

How are kindey stones treated?

Answer 18

By shockwave therapy, breaking up the stones more so they are easier to excrete

Question 19

What is Diabetes Mellitus?

Answer 19

The lack of insulin. This causes an increase of glucose in the blood, and the threshold level of glucose is easier to release. This makes your urine full of glucose.

Question 20

What is diabetes Insipidus?

Answer 20

A lack of ADH. A lack of ADH means you will not be able to retain water in your blood, and thus pee a lot more and be more dehydrated.

Question 21

What is Nephritis?

Answer 21

The inflamation of nephrons. A type of nephritis is the increased permeability of the glomerulus. Sometimes, large molecules will slip through, like proteins. Since there is no mechanism to reabsorb them, they will stay in your urine.

Question 22

What is Hemodialysis?

Answer 22

A type of dialysis where your blood is taken out of your body via tube and encounters dialysis fluid. This fluid has things your body needs, and by concentration gradients, your blood will absorb them and get rid of your wastes.

Question 23

If your blood is very acidic, what should they put in dialysis fluid?

Answer 23

They should put a base in your dialsys fluid, so that your blood will absorb the base and your blood will be neutralized

Question 24

What is peritoneal Dialysis

Answer 24

Peritoneal Dialysis is where they put dialysis fluid in your abdomen, so that your blood will go past and, just like hemodialsys, take in the things it needs through concentration gradients. Drained and replaced multiple times a day

Question 25

What are different types of Nitrogenous wastes? Why do animals have different ones?

Answer 25

Mammals hold their nitrogenous wastes by converting it to urea, so we can hold onto it for long.
Fish keep their nitrogenous waste as ammonia because they can exchange it at any time.
Birds and reptiles turn their nitrogenous waste to uric acid.