Zoology MCQs for NEET — Practice Questions with Answers

Angiotensinogen, which is converted to angiotensin I, is secreted by the liver. This protein plays a key role in the renin-angiotensin system, which helps regulate blood pressure and fluid balance.

Secretion of renin from Juxtaglomerular (JG) cells is stimulated by a fall in glomerular blood flow, glomerular blood pressure, and Glomerular Filtration Rate (GFR). Therefore, all these factors contribute to the secretion of renin.

ADH, also known as Antidiuretic Hormone or vasopressin, is secreted by the neurohypophysis, which is the posterior part of the pituitary gland. The neurohypophysis releases ADH in response to signals from the hypothalamus when the body needs to conserve water. This hormone acts on the kidneys to reduce water loss.

Angiotensin II is a hormone that plays a crucial role in the regulation of blood pressure and fluid balance. It stimulates the adrenal cortex to release aldosterone, which in turn increases sodium and water reabsorption in the kidneys, thereby increasing blood volume and pressure.

The elimination of insoluble calcium phosphate takes place primarily through the large intestine. Calcium phosphate is a component of feces and is excreted from the body through the digestive tract. The kidneys play a role in maintaining calcium and phosphate balance by excreting soluble forms of these minerals in urine, but insoluble calcium phosphate is handled by the large intestine.

The presence of blood in urine is known as hematuria. It is a condition where red blood cells are found in the urine, which can be a sign of various underlying health issues such as infections, kidney stones, or urinary tract disorders. Therefore, the correct answer is 'Hemetourea', although the correct medical term is 'Hematuria'.

Uremia is a condition characterized by an excess of urea and other nitrogenous waste compounds in the blood. It occurs when the kidneys are unable to filter these waste products efficiently, often due to kidney failure. This can lead to various symptoms, including fatigue, confusion, and nausea.

The kangaroo rat has the longest loop of Henle among the given options. This adaptation allows it to concentrate urine to a great extent, conserving water in the arid environments where it lives.