Bio Ch. 49 Urinary System

Front 1

3 urinary systems

Back 1

1. Blood (or equivalent fluid) is filtered, removing water and small dissolved substances
2. Nutrients are selectively reabsorbed from filtrate
3. Any remaining water and dissolved wastes are excreted from the body

Front 2

vertebrate kidneys

Back 2

-Dissolved wastes are removed from body, but at the expense of losing water
--Useful nutrients can also be lost in the urine
-[kidneys] evolved in vertebrates to minimize water and nutrient loss

Front 3

excretory systems

Back 3

-eliminate nitrogenous wastes resulting from protein digestion
--excreted as ammonia, urea, or uric acid

Front 4

excretory systems eliminate

Back 4

-nitrogenous wastes resulting from protein digestion
-excreted as ammonia, urea, or uric acid

Front 5

Urea formation process

Back 5

-Amino acids are deaminated within cells, ammonia is formed
-Ammonia is carried in the blood to the liver, where it is converted to urea
-Urea is carried in the blood to the kidneys, where it is excreted in urine
-important because urea is less toxic to cells than ammonia

Front 6

birds and reptiles convert urea to:

Back 6

uric acid, which is not very water soluable
--uric acid is released as a solid with little water loss

Front 7

4 structures that make up the human urinary system:

Back 7

Kidneys, Ureters, Bladder, Urethra

Front 8

arteries

Back 8

carry blood OUT of heart, also carry oxygen

Front 9

Rhythmic contractions of the ureter transports urine to the:

Back 9

bladder

Front 10

Urine flows from each kidney into a :

Back 10

muscular tube, called a ureter

Front 11

the bladder wall is:

Back 11

lined with smooth muscle and is expandable
--Accommodates about 500 milliliters of urine

Front 12

kidney anatomy: identify outer layer of tissue, overlying deeper tissues, and inner chamber

Back 12

-outer layer of tissue: renal cortex
-overlying deeper tissues: renal medulla
-subdivided inner chamber: renal pelvis
--collects urine and directs it into the ureter

Front 13

kidney tissue is made out of microscopic tubules called

Back 13

nephrons

Front 14

Bowman's capsule

Back 14

cuplike structure that contains a capillary glomerulus; blood is filtered here

Front 15

Tubule

Back 15

long twisted tube; composed of the proximal tubule, loop of Henle, and distal tubule

Front 16

Collecting ducts

Back 16

collect fluid from many nephrons and deposits it in the renal pelvis

Front 17

Loop of Henle

Back 17

-(in the renal medulla) forms a salt and urea concentration gradient around the nephron tubule and collecting duct
-the longer the loop, the stronger the gradient
-the most concentrated fluid surrounds the bottom of the loop

Front 18

role of kidneys

Back 18

-Regulate blood water content
-Regulate blood pressure and oxygen levels
-Monitor and regulate dissolved substances in blood

Front 19

The ability of kidneys to reabsorb water is under influence of:

Back 19

-antidiuretic hormone (ADH)
--Produced by the posterior pituitary
--Makes the distal tubule and collecting ducts more permeable to water

Front 20

hormone kidney releases into blood stream when blood pressure falls

Back 20

renin

Front 21

hormone released by kidneys when blood oxygen levels are low

Back 21

-erythropoietin
--stimulates bone marrow to make more red blood cells
--more red blood cells increase the oxygen carrying capacity of the blood