Wk 7 Urinary Flashcards
Afferent glomerular arteriole
The smallest arteriole branches
that carry blood into the renal glomerulus for filtration.
Aldosterone
A mineralocorticoid hormone secreted by the cortex
of the adrenal gland. It stimulates the kidney to conserve
sodium ions and water and to eliminate potassium and hydrogen ions
Antidiuretic hormone
A hormone released by the posterior pituitary. It facilitates water conservation in the body by
promoting water reabsorption from urine in the collecting
ducts. Low levels of ADH cause diabetes insipidus, a condition
that results in excessive water loss from the body through
increased urine volume.
Anurai
when the kidneys aren’t producing urine
Azotemia
A buildup of waste materials, particularly creatinine
and BUN, in the blood because of insufficient removal of these
substances by the kidneys.
Bowman’s capsule
Part of the renal corpuscle. It consists of two
layers: an inner, visceral layer that lies directly on the glomerular
capillaries and an outer, parietal layer. It functions as a plasma
filter in the process of urine formation.
Capsular space
The space between the visceral and parietal
layers of Bowman’s capsule.
Collecting duct
The system of tubules that collects tubular filtrate from the distal convoluted tubules and carries it to the
renal pelvis. They are not considered part of the nephron.
Cortex
the outer portion of the kidney. It contains the renal corpuscles, proximal convoluted tubules, distal convoluted tubules,
collecting ducts, and peritubular capillaries.
Distal convoluted tubule
The last tubular part of the
nephron before it enters the collecting duct. DCTs are found in
the kidney’s cortex.
Diuresis
Producing and passing large amounts of urine
Efferent glomerular arteriole
Arterioles that leave the glomeruli of the kidney. They are carrying blood that has been filtered by the glomeruli, so it contains less water. Blood in the
efferent glomerular arterioles has a higher concentration of
blood cells and plasma proteins than blood in the afferent glomerular arterioles.
Erythropoietin
The hormone produced by the kidney that stimulates the red bone marrow to increase its production of red
blood cells.
Fenestration
Small openings or holes (literally, windows); in the
walls of the glomerular capillaries, fenestrations allow certain
molecules to leave that would normally be too large to escape.
Glomerular filtrate
The fluid that has been filtered out of the
glomerular capillaries and into the capsular space.
Glomerular filtration rate
The rate at which plasma is
filtered into the capsular space. It is expressed in milliliters per
minute.
Glomerulus
The tuft of capillaries found in the renal corpuscle;
also called glomerular capillaries.
Glycosuria
The presence of glucose in the urine
Hilus
The isolated area of some organs where blood vessels and
other structures, such as nerves, enter and leave. For example,
the hilus of the kidney is the indented area on the medial side
where blood or lymph vessels and nerves enter and leave and
where the ureters leave the organ. The hilus of the lung is where
air passageways, blood, lymph vessels, and nerves enter and
leave.
Loop of Henle
The middle part of the tubular portion of a
nephron. It has a descending part that travels from the cortex
to the medulla and an ascending part that travels back to the
cortex. The loop of Henle is located between the proximal convoluted tubule and the distal convoluted tubule.
Medulla
The inner part of the kidney. It contains the loop of Henle,
peritubular capillaries, and collecting ducts.
Micturition
The process of expelling urine from the body; also
called urination or uresis
Nephron
The basic functional unit of the kidney. It is composed
of the renal corpuscle and the tubule system, which is made up
of the proximal convoluted tubule, loop of Henle, and distal
convoluted tubule
Oliguria
Passing small amounts of urine.
Osmotic diuresis
Diuresis produced by excess dissolved substances
in the fluid circulating through the tubules of the nephrons. The
excess glucose in the tubular fluid of animals with diabetes mellitus produces an osmotic diuresis that results in polyuria.
Peritubular capillary
Capillaries within the kidneys
Podocyte
Meaning “foot cells.” Podocytes make up the visceral
layer of Bowman’s capsule in the kidney. Podocytes form a permeable covering on the outside of the glomerular capillaries.
Polydipsia
Excessive thirst.
Polyuria
Production of an excessive volume of urine.
Postrenal uremia
usually associated with an obstruction
that prevents urine from being expelled from the body
Prerenal uremia
associated with decreased blood flow to
the kidneys and may be caused by conditions such as dehydration, congestive heart failure, or shock, if these conditions are
left untreated.
Prostaglandin
hormonelike substances that are produced and exert many effects locally in a variety of body tissues.
Sometimes called tissue hormones because they regulate biochemical activities in the tissues where they are formed.
Proximal convoluted tubule
The first part of the tubular
portion of a nephron.Its lumen is a continuation of the capsular
space of Bowman’s capsule in the renal corpuscle. The majority
of tubular reabsorption takes place from the PCT.
Reabsorption
The process by which some constituents of plasma
that were filtered out of the plasma by the glomerulus are
returned to the bloodstream. Water, glucose, amino acids, and
sodium are some of the substances that are reabsorbed.
Renal corpuscle
The first part of the nephron. It is composed of
the glomerular capillaries and Bowman’s capsule. The capsular
space of the renal corpuscle continues as the proximal convoluted tubule
Renal pelvis
The collection point for tubular filtrate as it leaves
the collecting ducts. When the fluid enters the renal pelvis, it is
in the form of urine that must be eliminated from the body. The
renal pelvis continues as the ureter that carries urine to the
urinary bladder.
Renal uremia
associated with an inability of the kidney
to regulate urine production adequately because of damage to
the nephrons
Renin
A hormone released in the kidney (by the juxtaglomerular
cells of the afferent glomerular arterioles) in response to low
blood pressure
Renin-angiotensin-aldosterone
system
A sequence of hormonal reactions, initiated by the kidneys in response to low
blood pressure, which results in vasoconstriction and increased
blood volume
Retroperitoneal
Behind the parietal layer of peritoneum that
lines the abdominal cavity, outside the abdominal cavity proper
The glomerular capillary
Most of the plasma protein
molecules are too large to pass through the glomerular capillary fenestrations.
Trigone
The triangular body of the urinary bladder located
between the openings of the ureters and the urethra.
Tubular filtrate
The glomerular filtrate after it has passed into the
proximal convoluted tubule. It will be called the tubular filtrate
throughout its entire journey through the nephron tubules even
though its chemical composition will change many times before
it enters the collecting duct.
Uremia
Urine in the blood. Refers to a buildup of waste materials,
especially urea, in the blood because of insufficient removal by
the kidneys
Uresis
Expelling urine from the body; also called micturition or
urination.
Ureter
The muscular tubes that leave the kidney at the hilus and
connect to the urinary bladder. They move urine to the bladder
by peristaltic smooth muscle contractions.
Urinary calculi
Uroliths or urinary tract stones.
Urolith
Urinary tract stones; precipitated aggregates of mineral
crystals that form macroscopic stones or sand anywhere in the
urinary tract.
