A&P 2: TopHat Lab 16

Kidney

Primary excretory organ of the body; filters the blood; keeps useful molecules and ions; gets rid of toxins, and metabolic wastes; regulates the volume of the blood by excreting or retaining water; regulates blood pressure by adjusting blood volume; regulates the pH of the blood by excreting excess H+ ions, which contribute to blood acidity; involved in the production of red blood cells, and the synthesis of vitamin D; approximately 11-12 cm long, 5-7 cm wide, and 3 cm thick; located in the lumbar region on either side of the spine, and lay against the body wall; embedded in fat, and lay beneath the parietal peritoneum; connected to the dorsal aorta by the renal arteries, and to the posterior vena cava by the renal veins

Urethra

Exits the urinary bladder and carries the urine to the outside

Renal cortex

Superficial layer of the kidney; shaded dark brown due to the dense system of blood vessels that aid in the filtering of blood in the kidney

Renal medulla

Inner layer of the kidney that contains the renal pyramids

Renal pyramid

Series of darker, conical regions found in the renal medulla; majority of nephron tubules occur in these regions

Renal columns

Inward extensions of the renal cortex into the renal medulla; separate the renal pyramids and help distinguish the different lobes of the kidney

Renal papillae

Tips at the base of the renal pyramids that project into a minor calyx; drain urine from the pyramids into the minor calyxes.

Minor calyx

Cup-shaped cavity at the base of the renal papilla; drains urine from the renal papillae into the major calyxes

Major calyx

Cavity formed by the convergence of several minor calyces; drains urine from the minor calyxes into the renal pelvis

Renal pelvis

Funnel-shaped cavity formed by the convergence of the major calyxes; collects urine from the major calyxes and joins the ureter

Ureter

Tube that conducts urine from the renal pelvis and kidney to the urinary bladder for storage

Renal capsule

Connective tissue covering the external surface of the kidney

Renal artery

Vessel which carries oxygenated blood from the aorta to the kidney to be filtered

Renal vein

Vessel that carries un-oxygenated and filtered blood from the kidney to the inferior vena cava

Leukocytes in Urine

Urine is normally sterile. Therefore, the presence of white blood cells in the urine suggests a urinary tract infection

Nitrite in Urine

Formed when bacteria in the urine change nitrate to nitrite; presence of this compound indicates a probable urinary tract infection

pH of Urine

Measure of the acidity or alkalinity of the urine; factors such as drugs, diet, time of day, and health affect the pH of urine. Normal pH of urine is 6.0, but can range from 4.5 to 8.0.

Protein in Urine

Large molecules not normally found in the urine, or only in small amounts; presence may be caused by severe emotional stress, strenuous exercise, fever or chronic causes may include diabetes, malaria, heart disease, high blood pressure, sickle cell anemia, or even pregnancy

Glucose in Urine

Usually reabsorbed by the kidney and is not found in urine; high glucose levels in urine can indicate diabetes, kidney damage, or stress

Ketone in Urine

Produced when fat is metabolized for energy; may indicate a low carbohydrate diet, starvation, or ketoacidosis.

Ketoacidosis

Life-threatening chemical imbalance that occurs in people with diabetes; caused when cells do not get enough glucose to meet energetic demands and begin breaking down fat for energy

Bilirubin in Urine

Not normally found in urine; formed from the breakdown of red blood cells; may indicate liver damage, or blockage of the flow of bile from the gallbladder

Urobilinogen in Urine

Usually only present in small amounts; forms from the breakdown of bilirubin; eliminated from the body through the bile, and goes into the digestive tract; may indicate liver damage or blockage of the flow of bile from the gallbladder

Blood

Normally not filtered by the kidney because they are too large to pass through the glomerulus; indicates damage to the kidney caused by inflammation, kidney stones, kidney disease, or blunt trauma. Menstruating females often show a positive result of this test, although the cells are not coming from the urinary system.

Identify A

Renal Pyramid - picture

Identify B

Renal Column - picture

Identify C

Renal cortex - picture

Identify D

Minor Calyx - picture

Identify E

Renal Pelvis - picture

Identify F

Ureter - picture

Identify G

Major Calyx - picture

Identify I

Renal Papilla - picture

Cells in Urine

Epithelial cells result from a sloughing off of the lining of the urinary tract into the filtrate; presence of blood cells in the urine may indicate inflammation of the urinary tract or a urinary disease

Casts in Urine

Hardened proteins and cells that can form plugs in the shape of the distal convoluted renal tubule, or collecting duct; flushed from the tubules by the urine; form in very acidic urine, when proteins are present, and/or when the urine is very concentrated

Crystals in Urine

Form when minerals crystallize in the urine, due to either highly acidic or basic urine pH; normally, people have a few of these in their urine; may indicate kidney stones, or a metabolic problem

Centrifuge

Device that uses rapid rotation to generate high centrifugal force, separating substances of different densities

Method used for obtaining the sediments from the urine and making wet mount

1. Fill a centrifuge tube to the appropriate level indicated by the instructor.

2. Place the centrifuge tube in the centrifuge according to the instructions of your instructor.

3. Close the lid of the centrifuge.

4. Spin the urine at a speed of 15000 rpm for five minutes.

5. Obtain a clean microscope slide and coverslip. Put a drop of methylene blue stain on the center of the slide.

6. Pipette a drop of urine sediment onto the stain, in the center of the microscope slide.

7. Place the cover slip on the slide.

8. Examine the sediment under low and high magnification and look for the solid components

Squamous Epithelial Cells in Urine

Flat nucleated cells that shed from the lining of the urethra; have a large, non-uniform appearance

Transitional Epithelial Cells in Urine

Rough cuboidal cells that shed from the lining of the ureters, urinary bladder, and renal pelvis of the kidneys

Erythrocytes in Urine

RBCs found in urine; presence may indicate some kind of kidney damage

Leukocytes in Urine

Nucleated WBCs; presence may indicate a urinary tract infection

Erythrocyte Cast in Urine

A precipitate of RBCs in the shape of a tubule or duct

Leukocyte Cast in Urine

A precipitate of WBCs in the shape of a tubule or duct

Granular Cast in Urine

A precipitate of cells that remained in the duct but degenerated into a granular cast

Hyaline Casts in Urine

A cast composed of RBCs, WBCs, and oval fat droplets

Calcium Oxalate Crystals in Urine

Greenish crystals usually in the shape of an octahedron (polygon with 8 sides)

Uric Acid Crystals in Urine

Yellow to reddish-brown crystals, highly variable in shape

Calcium Phosphate Crystals in Urine

Have various forms, including six to eight sided prisms appearring in single or rosette shapes