Urinalysis Lab

Question 1

What does the excretory system consist of?

Answer 1

kidneys, ureters, bladder, and urethra

Question 2

What are the primary functions of the excretory system?

Answer 2

• excretion (eliminating metabolic waste products)
• regulates the amount of water in the body
• regulates concentrations of various electrolytes in the body fluids
• regulates the pH of blood.

Question 3

what are the six roles kidneys play in the establishment of homeostasis?

Answer 3

1. excretion of metabolic wastes products
2. reabsorption of water and important nutrients
3. regulation of plasma ion composition
4. acid-base homeostasis
5. blood pressure regulation
6. hormone secretion

Question 4

what are the three major regions of the kidney

Answer 4

1. renal cortex
2. renal medulla
3. renal pelvis

Question 5

Urine produced by the kidneys is sent for storage in the bladder by the ________, which are continuous with the renal pelvis. From the bladder, urine is drained by the ________.

Answer 5

ureters, urethra.

Question 6

what is the functional unit of the kidney?

Answer 6

nephron

Question 7

what is each nephron composed of?

Answer 7

• initial filtering component (the renal corpuscle)
• tubule specialized for reabsorption and secretion (the renal tubule)

Question 8

renal corpuscle

Answer 8

initial filtering component

Question 9

renal tubule

Answer 9

tubule specialized for reabsorption and secretion

Question 10

where is the renal corpuscle located?

Answer 10

located within the renal cortex

Question 11

what does the renal corpuscle consist of?

Answer 11

consists of the glomerulus and Bowman’s capsule.

Question 12

Glomerulus

Answer 12

A capillary tuft that receives its unfiltered blood supply from an afferent arteriole of the renal circulation.

Question 13

what does the glomerular blood pressure provide?

Answer 13

Provides the driving force for fluid and solutes to be filtered out of the blood and into the space made by Bowman’s capsule.

Question 14

Non-filtered blood passes into the_______ ______ which then moves into the ______ _____ (collecting capillaries intertwined with the convoluted tubules) where substances may be secreted or reabsorbed or further down the nephron.

Answer 14

efferent arteriole, vasa recta

Question 15

vasa recta

Answer 15

collecting capillaries intertwined with the convoluted tubules

Question 16

Efferent venules from other nephrons combine to form the ____ _____?

Answer 16

renal vein

Question 17

What is the Bowman’s capsule composed of?

Answer 17

Composed of an inner visceral (simple squamous epithelial cells) and outer parietal (simple squamous epithelial cells) layers.

Question 18

What is the visceral layer of the Bowman’s capsule made of?

Answer 18

made of podocytes

Question 19

what is the function of podocytes?

Answer 19

Send foot processes that interdigitate over the glomerulus forming filtration slits.

Question 20

ultrafiltration (= glomerular filtration)

Answer 20

process of filtration of the blood

Question 21

what is he normal rate of filtration?

Answer 21

125 ml/min

Question 22

Small molecules (e.g., water, glucose, ions, amino acids, urea) pass freely through the slits. However, large molecules (e.g., proteins such as albumin) and cells (e.g., red blood cells and platelets) cannot pass. The filtrate enters the space
located between the visceral and parietal layers called the Bowman’s space.

Question 23

Bowman’s space

Answer 23

The space located between the visceral and parietal layers of the Bowman’s capsule

Question 24

what does the convoluted tubule consist of?

Answer 24

This tubule contains a single layer of cuboidal cells surrounding the lumen. These cells are covered with microvilli which increases the surface area for reabsorption

Question 25

In addition to water, approximately ________ of the ions and almost all of the filtered organic solutes (e.g., glucose and amino acids) entering the proximal convoluted tubule are actively reabsorbed into surrounding the _______ ______.

Answer 25

two-thirds, peritubular capillaries.

Question 26

From the proximal convoluted tubule, filtrate enters the _____ __ _____ which extends down into the renal medulla.

Answer 26

loop of Henle, renal medulla

Question 27

What is the primary role of the Loop of Henle?

Answer 27

to concentrate the salt in the surrounding medullary space.

Question 28

The descending limb of the loop of Henle is ________to water but ________ to solutes, thus water moves across the tubular wall into the medullary space and making the filtrate ________.

Answer 28

permeable, impermeable, hypertonic

Question 29

The filtrate then enters the ascending limb which is ______ to water. In this region, Na+ , Cl− , and K+ are actively transported into the ________ ______, now making the filtrate hypotonic and the medullary space hypertonic (very salty).

Answer 29

impermeable, medullary space

Question 30

Active transport of these ions from the ascending limb creates an osmotic pressure drawing water from the ________ ____ into the ________ _____.

Answer 30

descending limb, medullary space

Question 31

where is the distal convoluted tubule located?

Answer 31

Located back in the renal cortex.

Question 32

what does the distal tubule do?

Answer 32

excretes H+ and ammonium to regulate pH.

Question 33

what is secreted into the distal tubule?

Answer 33

urea

Question 34

what does the distal convoluted tubule do?

Answer 34

delivers filtrate to the collecting ducts that begin in the
renal cortex and extend deep into the medulla

Question 35

The bladder is voided by the process of?

Answer 35

micturition via the urethra.