Free Homeostasis MCQs with Answers
698 Homeostasis MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Homeostasis maintains a stable internal environment through the kidney and urinary system, thermoregulation and excretion. The kidney topics include filtration, selective reabsorption, urine formation and water balance, while thermoregulation involves sweating, vasodilation, vasoconstriction and hormonal control; excretion is different from egestion, which removes undigested food.
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Read the Homeostasis notesFree MDCAT chapter notes with key terms698 questions · page 19 of 35
361. Which structure receives about 20% of total blood and has a weight less than 1% of the total body:
- A. Heart
- B. Lungs
- C. Kidney
- D. Liver
Explanation: Option C is correct.The kidneys receive approximately 25% of cardiac output or 1250 ml/min via the renal arteries.
Correct answer: Kidney- A. Overcooled body
- B. Bacteria
- C. Environmental changes
- D. Pollution
Explanation: Option A is correct.The hairs in mammals act as insulating organs and reduce heat loss.
Correct answer: Overcooled body- A. Kidney
- B. Gills
- C. Skin
- D. All of the above
Explanation: Option A is correct.The kidneys in fishes play a vital role in osmoregulation, helping maintain the balance of water and salts in their…
Correct answer: Kidney- A. Winter
- B. Summer
- C. Autumn
- D. Spring
Explanation: Option A is correct.Correct! Amphibians, as poikilothermic organisms, hibernate in winter when the environment gets too cold for them to…
Correct answer: Winter- A. Renal pelvis
- B. Hilum
- C. Medulla
- D. Pyramid
Explanation: Option B is correct.The hilum is the indentation on the medial side of the kidney through which the renal artery enters and the renal vein…
Correct answer: Hilum- A. Ammonia
- B. Urea
- C. Uric acid
- D. Fatty acid
Explanation: Option C is correct.The correct answer is uric acid, which is the least toxic excretory product.
Correct answer: Uric acid- A. Xerophytes
- B. Mesophytes
- C. Hydrophytes
- D. Halophytes
Explanation: Option C is correct.Potamogeton is a genus of aquatic plants commonly known as pondweed.
Correct answer: Hydrophytes- A. Polydipsia
- B. Polyuria
- C. Polyphagia
- D. Polyanypsida
- E. Both A and B
Explanation: Option B is correct.Polyuria is defined as the production of an abnormally large volume of urine.
Correct answer: Polyuria- A. Hagfish
- B. Freshwater fish
- C. Bonyfish
- D. Cartilaginous fishes
Explanation: Option B is correct.Bony fishes live in marine ecosystems and they do not have specialised organs to cope up with extreme salty…
Correct answer: Bonyfish- A. The cells of the tubules detect the osmotic pressure of the blood
- B. Water is extracted from the glomerular filtrate in the proximal tubule
- C. The kidney produces hyptonic urine
- D. Hormones increase the permeability of the collecting ducts
- E. A low solute concentration is maintained around the collecting ducts
Explanation: Option D is correct.Water excretion by the kidney is regulated by the peptide hormone vasopressin.
Correct answer: Hormones increase the permeability of the collecting ducts- A. Urethra
- B. Ureter
- C. Uterus
- D. Eustachian tube
- E. Bile duct
Explanation: Option B is correct.Ureter is the tube that brings urine from kidney to the urinary bladder.So, Option B is correct.Option A: Urethra tube…
Correct answer: Ureter- A. Reptiles
- B. Turtles
- C. Mammals
- D. Fish
- E. None of these
Explanation: Option D is correct.Ammonia is a toxic by product of the metabolic removal of nitrogen from proteins and nucleic acids.
Correct answer: Fish- A. Loop of vessels
- B. Tubular epithelium
- C. Ball of capillaries
- D. Cup-shaped swelling
Explanation: Option C is correct.The glomerulus (plural glomeruli) is a network of small blood vessels (capillaries) known as a tuft, located at the…
Correct answer: Ball of capillaries- A. Malpighian tubules
- B. Protonephridia
- C. Metanephridia
- D. Nephron
Explanation: Excretion in Planaria takes place through **protonephridia** (Option B).
Correct answer: Protonephridia375. The movement of water to a lower solute concentration area through a semipermeable membrane is?
- A. Osmotic Potential
- B. Pressure potential
- C. Soil potential
- D. Solute potential
Explanation: The movement of water to a lower solute concentration area through a semipermeable membrane is called **osmotic potential** (Option A).
Correct answer: Osmotic Potential- A. A condition in which abnormally large volume of urine is produced
- B. A condition of exessive thirst
- C. A condition of excessive hunger
- D. A condition in which the concentration of blood decreases in the body
Explanation: Option B is correct.The term polydipsia refers to a condition of excessive thirst.
Correct answer: A condition of exessive thirst- A. Aldosterone
- B. Antidiuretic hormone (ADH)
- C. Parathyroid hormone (PTH)
- D. Atrial natriuretic peptide (ANP)
Explanation: Aldosterone is a hormone produced by the adrenal cortex that promotes the reabsorption of sodium ions (Na+) in the distal convoluted…
Correct answer: Aldosterone- A. Osmotic Pressure
- B. Soil potential
- C. Solute potential
- D. Solvent potential
Explanation: Osmotic pressure is the pressure exerted by a solution when it is separated by a semi-permeable membrane from pure water.
Correct answer: Osmotic Pressure- A. Steroid hormone
- B. Catechol amine
- C. Peptide hormone
- D. Glycoprotein
Explanation: Chemically, vasopressin is a peptide hormone, particularly nonapeptide (i.e. having nine amino acids).
Correct answer: Peptide hormone- A. Fluid retention
- B. Vasodilation
- C. Muscular expansion
- D. Vasoconstriction
- E. Vascular contraction
Explanation: Vasoconstriction is the narrowing of blood vessels, which reduces blood flow and increases blood pressure.
Correct answer: Vasoconstriction