Excretory System | Mock Test | Staff Nurse | Guides Academy

Excretory System - Structure and function of kidney, formation and composition of urine, fluid and electrolyte balance

The excretory system plays a vital role in removing waste products and maintaining the body’s internal balance of water and salts. Its main organs include the kidneys, ureters, urinary bladder, and urethra. The kidneys filter blood to remove excess water, urea, and other waste materials, forming urine. This urine travels through the ureters to the bladder, where it is stored before being expelled through the urethra. The excretory system helps regulate blood pressure, pH levels, and electrolyte balance, ensuring the body’s internal environment remains stable and healthy.

Time: 15:00

What is the primary function of the kidneys in the excretory system?

[a] To produce hormones for digestion

[b] To filter blood, remove waste products, and maintain fluid balance

[c] To store urine before it is expelled

[d] To transport oxygen to body tissues

What is the microscopic, functional filtering unit of the kidney called?

[a] Medulla

[b] Renal pelvis

[c] Nephron

[d] Calyx

The cluster of tiny blood capillaries found within the Bowman's capsule where filtration begins is the:

[a] Loop of Henle

[b] Glomerulus

[c] Peritubular capillary

[d] Afferent arteriole

Which of the following represents the correct order of filtrate flow through a nephron?

[a] Collecting Duct -> Bowman's Capsule -> Loop of Henle -> PCT -> DCT

[b] Loop of Henle -> PCT -> DCT -> Bowman's Capsule -> Collecting Duct

[c] Bowman's Capsule -> Collecting Duct -> PCT -> Loop of Henle -> DCT

[d] Bowman's Capsule -> PCT -> Loop of Henle -> DCT -> Collecting Duct

The first step in the formation of urine, which occurs in the glomerulus, is:

[a] Tubular secretion

[b] Tubular reabsorption

[c] Glomerular filtration

[d] Micturition

Under normal conditions, which of the following substances should NOT be found in the glomerular filtrate?

[a] Glucose

[b] Water

[c] Urea

[d] Large proteins and blood cells

The process of selectively moving substances from the filtrate back into the blood is known as:

[a] Secretion

[b] Reabsorption

[c] Filtration

[d] Excretion

In which part of the nephron does the majority of tubular reabsorption occur?

[a] Loop of Henle

[b] Distal convoluted tubule (DCT)

[c] Proximal convoluted tubule (PCT)

[d] Glomerulus

What is the primary nitrogenous waste product found in human urine?

[a] Ammonia

[b] Urea

[c] Creatine

[d] Uric acid

Which hormone, released from the posterior pituitary gland, increases the permeability of the collecting ducts to water, thereby concentrating urine?

[a] Aldosterone

[b] Renin

[c] Antidiuretic hormone (ADH)

[d] Erythropoietin

The hormone Aldosterone primarily functions to regulate the balance of which two electrolytes?

[a] Calcium and Phosphate

[b] Sodium and Potassium

[c] Chloride and Bicarbonate

[d] Magnesium and Hydrogen

What is the primary stimulus for the release of aldosterone from the adrenal cortex?

[a] High blood glucose

[b] Dehydration and high blood osmolarity

[c] Low blood pressure and the activation of the renin-angiotensin system

[d] High blood pH

The kidneys help regulate blood pH by:

[a] Producing buffers for the blood

[b] Secreting aldosterone

[c] Secreting hydrogen ions (H+) and reabsorbing bicarbonate ions (HCO3-)

[d] Filtering out carbon dioxide

The tube that transports urine from the kidney to the urinary bladder is the:

[a] Urethra

[b] Ureter

[c] Collecting duct

[d] Renal artery

The presence of glucose in the urine, often a sign of diabetes mellitus, is called:

[a] Hematuria

[b] Proteinuria

[c] Glycosuria

[d] Ketonuria

What is the main driving force that pushes fluid and solutes out of the glomerulus and into the Bowman's capsule?

[a] Osmotic pressure of the blood

[b] Active transport by nephron cells

[c] The negative charge of the filtration membrane

[d] Glomerular hydrostatic (blood) pressure

The muscular sac that stores urine before it is expelled from the body is the:

[a] Kidney

[b] Urinary bladder

[c] Renal pelvis

[d] Ureter

The inner region of the kidney, containing the renal pyramids, is called the:

[a] Renal cortex

[b] Renal capsule

[c] Renal medulla

[d] Renal hilum

Tubular secretion is a process that moves substances from the:

[a] Filtrate into the nephron tubule

[b] Blood (peritubular capillaries) into the filtrate

[c] Glomerulus into the Bowman's capsule

[d] Filtrate back into the blood

What is the primary stimulus for the release of antidiuretic hormone (ADH)?

[a] An increase in blood pressure

[b] An increase in blood volume

[c] An increase in blood osmolarity (dehydration)

[d] An increase in blood pH

The presence of red blood cells in the urine is a condition known as:

[a] Anuria

[b] Pyuria

[c] Hematuria

[d] Glycosuria

The central collecting region in the kidney that receives urine from the calyces and funnels it into the ureter is the:

[a] Renal cortex

[b] Renal pelvis

[c] Renal pyramid

[d] Renal capsule

In response to dehydration, the body will secrete more ADH, resulting in urine that is:

[a] Greater in volume and more dilute

[b] Greater in volume and more concentrated

[c] Smaller in volume and more dilute

[d] Smaller in volume and more concentrated

Which of these is NOT a normal constituent of urine?

[a] Water

[b] Sodium ions

[c] Glucose

[d] Creatinine

The process of voiding the bladder is scientifically termed:

[a] Filtration

[b] Defecation

[c] Mastication

[d] Micturition