Test: Human Physiology: Endocrine System - NEET MCQ

The basal metabolic rate of the body is controlled by the hormones T3 and T4 (Thyroxine), produced by the thyroid gland in response to the thyroid stimulating hormone (TSH), produced by the anterior pituitary. T3 and T4 bind to receptors on the mitochondria, causing an increase in the production of ATP, as well as an increase in the transcription of genes that help utilize glucose and produce ATP, resulting in the higher metabolism of the cell.  When blood glucose levels rise, insulin is secreted by the pancreas, lowering blood glucose by increasing its uptake in cells and stimulating the liver to convert glucose to glycogen, in which form it can be stored. Cortisol (or hydrocortisone) is the most important human glucocorticoid. In the fasted state, cortisol stimulates gluconeogenesis in the liver. This pathway results in the synthesis of glucose from non-carbohydrate substrates, such as amino acids and glycerol from triglyceride breakdown. Thus, all the three play an important role in the carbohydrate metabolism.

The spleen consists of two different tissue types red pulp and white pulp. Red pulp, also called as splenic pulp, consists of blood and reticular fibers. This portion of the human spleen helps to filter the aged/damaged red blood cells. White pulp also called Malpighian bodies of the spleen or splenic lymphoid nodules refers to small nodules within the spleen that are rich in lymphocytes and help to fight infection. Those are the main functions of the spleen. The spleen does not have any endocrine function and does not secrete any hormones. So, the correct answer is option B.

Diabetes and Urine Composition:


When it comes to diabetes, the composition of urine can provide valuable insights into the condition. Here are the key components that can be found in the urine of individuals with diabetes:
1. Sugar:
- High blood sugar levels in diabetes can lead to the presence of excess glucose (sugar) in the urine. This condition is known as glucosuria.
- Glucosuria occurs when the blood sugar levels exceed the renal threshold, causing the kidneys to excrete the excess glucose in the urine.
2. Ketones:
- Ketones are byproducts of fat metabolism that are normally produced in small amounts. However, in uncontrolled diabetes or when insulin is deficient, the body may start breaking down fat for energy, leading to an increase in ketone production.
- Ketones can be detected in the urine through a test called a urine ketone test. The presence of ketones in the urine may indicate diabetic ketoacidosis (DKA), a serious complication of diabetes.
3. Protein:
- In some cases, diabetes can cause damage to the kidneys, leading to a condition called diabetic nephropathy.
- Diabetic nephropathy is characterized by the presence of protein in the urine, a condition known as proteinuria.
- Proteinuria may indicate kidney dysfunction and is an important marker of diabetic kidney disease.
4. Other Components:
- Although not specific to diabetes, urine may also contain other components such as salt (sodium chloride) and fat (lipids) which can be influenced by dietary factors and overall health.
It is important to note that the presence of these components in urine is not exclusive to diabetes and can also be observed in other conditions. Therefore, it is crucial to consult a healthcare professional for proper diagnosis and management of diabetes. Regular monitoring of blood glucose levels and urine analysis can help in the assessment of diabetes control and the early detection of complications.

It is a polypeptide of 27 amino acids. It is secreted by cells in the duodenum when they are exposed to the acidic contents of the emptying stomach. It stimulates the exocrine portion of the pancreas to secrete bicarbonate into the pancreatic fluid (thus neutralizing the acidity of the intestinal contents).

Because if there will be a rise in blood pressure ultimately the heart beat rises and ADH is secreted when there is loss of water (it can be taken as adverse conditions)

Both are required in small amount.
Enzymes present very low amount in the cell and they do not altered during reaction.a small amount of enzyme can catalyze between 1 to 1000 molecules substrate per hour.
Hormones: The main function of endocrine gland is to secrete hormones directly into bloodstream. Very small amount of hormones can trigger very large response in the body.each type of hormone influences only certain organ and tissue.

Explanation:
The largest amount of iodine is found in the thyroid gland. The thyroid gland is responsible for producing thyroid hormones, which are essential for the regulation of metabolism and growth. Iodine is a crucial component of these hormones, and the thyroid gland has the highest concentration of iodine in the body.
Reasoning:
- Iodine is an essential mineral that is required for the production of thyroid hormones.
- The thyroid gland is responsible for synthesizing and releasing thyroid hormones.
- The thyroid gland actively takes up iodine from the bloodstream and incorporates it into thyroid hormones.
- The thyroid gland requires a significant amount of iodine to produce an adequate amount of thyroid hormones.
- Therefore, the thyroid gland contains the largest amount of iodine in the body.
Summary:
In summary, the largest amount of iodine is found in the thyroid gland. This is because the thyroid gland requires a significant amount of iodine to produce thyroid hormones, and therefore, it has the highest concentration of iodine in the body.

When it comes to hydration, water is the best option for people with diabetes. That's because it won't raise your blood sugar levels. High blood sugar levels can cause dehydration. Drinking enough water can help your body eliminate excess glucose through urine.

Adrenaline is a hormone secreted by adrenal medulla under an emergency condition to prepare the body for flight or fight response by increasing the intensity of the effect of sympathetic stimulation and response. The pituitary gland regulates secretions of other glands. Thyroid gland serves to regulate the basic metabolic rate. Parathyroid gland regulates blood calcium and phosphate level. Thus, the correct answer is D.

The posterior pituitary is often termed the neurohypophysis because the hormones of this part of the pituitary are released directly from the axonal endings of their source neurons into the circulation.

Secretion of the posterior pituitary hormones is directly from magnacellular neurons of the paraventricular and supraoptic nuclei into the circulation. These neurons project axons into the posterior pituitary via the hypothalamo-neurohypophyseal tract and terminate on a capillary bed of the inferior hypophyseal artery. Control of release in this system is under neural control and so this represents a reflex system with neural input and hormonal output.

The chemical substances that are secreted by cells/tissues or glands are categorised as biological substances. It includes digestive juices, hormones and other secretions. Gastrin, thyroxin and oxytocin are the hormones secreted by stomach, thyroid gland and posterior pituitary respectively. These are biochemical substances. Creatinine is a breakdown product of creatine phosphate and does not fall under the biological category of chemical substances. Thus, the correct answer is D.

Anterior pituitary secretes gonadotropins (FSH and LH). Follicle stimulating hormone (FSH) and LH promote the development of gametes and production of sex hormones by leydig cells and developing follicles in male and females respectively. Human chorionic gonadotropin is a placental hormone that maintains the corpus luteum to continue the secretion of progesterone and estrogens till placenta takes over secretion of progesterone and estrogen during pregnancy. Insulin regulates blood sugar level and is not involved in secretion of sex hormones. Thus, the correct answer is D.

• Excess secretion of growth hormones in adults especially in middle age can result in severe disfigurement which is known as Acromegaly, which may lead to serious complications.
• The disease is hard to diagnose in the early stages and often goes undetected for many years.

Insulin and glucagon are hormones, they control/balance the blood sugar level in the body. They both are produced in the Pancreas (Langerhans Islets), Insulin by the beta cells, and Glucagon by the alpha cells.

They are antagonistic, meaning, they have opposite effects:

1. If the blood sugar (glucose) level is high, insulin is released. Insulin lowers the level by certain reactions (skeletal muscle cells and fat cells remove (and store) more glucose, also more glucose gets converted to glycogen in the liver, - also for storage, etc)

2. If the blood sugar (glucose) level gets low, glucagon is released. Glucagon activates the stored glycogen to convert back into glucose and be released into the blood stream, thus raising the level.

In healthy individuals these 2 hormones keep the blood sugar level in balance.

Islets of Langerhans are the cells in the pancreas. The β- cells of Langerhans produce insulin which is the hormone required for the regulation of the blood sugar. 
The anterior part of the pituitary gland secretes the Follicle Stimulating Hormone. Follicle stimulating hormone is one of the hormones essential to pubertal development and the function of women's ovaries and men's testes. In women, this hormone stimulates the growth of ovarian follicles in the ovary before the release of an egg from one follicle at ovulation. It also increases oestradiol production.
The function of the thyroid gland is to take iodine, found in many foods, and convert it into thyroid hormones: thyroxine (T4) and triiodothyronine (T3). Thyroid cells are the only cells in the body which can absorb iodine. These cells combine iodine and the amino acid tyrosine to make T3 and T4.
The parafollicular cells of thyroid gland secrete calcitonin. The hormone helps in the regulation of calcium and phosphorus in the blood. The female ovary has got nothing to do with Calcitonin.
Hence, the correct option is Option C.

The adrenal cortex—the outer part of the gland—produces hormones that are vital to life, such as cortisol (which helps regulate metabolism and helps your body respond to stress) and aldosterone (which helps control blood pressure).

The pars distalis region of pituitary produces growth hormone, prolactin, thyroid-stimulating hormone, adrenocorticotrophic hormone, luteinizing hormone, and follicle-stimulating hormone.

Vitamin D is a hormone and is mostly produced by our skin in due to sunlight and can also be found in the food eaten. The liver and kidney convert the vitamin D into active hormone which is called calcitriol. It is required to absorb calcium from our stomach into the blood.
Thyroxine is a hormone secreted by the thyroid gland. It helps in regulating the metabolic rate, heart rate maintenance of bones etc.
Adrenaline is a hormone secreted by the medulla of the adrenal glands. It functions as a chemical mediator and also transmit nerve impulse to various organs.
So, all of the above are hormones. So,the answer is D.

The correct answer is option D: 2

- The hypothalamus is indeed the basal part of the diencephalon.
- The hypothalamus does not contain ganglia but contains neurosecretory cells.
- GnRH from the hypothalamus does stimulate the anterior pituitary to release gonadotropins.
- The posterior pituitary is under direct neural regulation, not chemical regulation, by the hypothalamus.

Aldosterone of the adrenal cortex is life-saving hormone because it serves to retain sodium and water to maintain a sufficient blood volume for circulation. So, it maintains the osmolarity and volume of ECF. The pituitary gland regulates secretion of other endocrine glands. Pineal gland secretes melatonin that regulates body’s daily rhythms. Thyroid hormones regulate the basic metabolic rate. Thus, the correct answer is C.

Neurohypophysis (pars nervosa), also known as posterior pituitary, stores and releases two hormones called oxytocin and vasopressin.

Male Sex Hormones:
- Androgens: Androgens are male sex hormones that play a crucial role in the development and maintenance of male reproductive tissues and secondary sexual characteristics. They are primarily produced in the testes and include testosterone, dihydrotestosterone (DHT), and androstenedione.
- Insulins: Insulins are peptide hormones produced by the pancreas that regulate blood sugar levels. They are not male sex hormones.
- Aldosterones: Aldosterones are mineralocorticoid hormones produced by the adrenal glands. They primarily regulate electrolyte and water balance in the body and are not male sex hormones.
- Pheromones: Pheromones are chemical substances produced by organisms to communicate with others of the same species. While they can influence reproductive behavior, they are not considered male sex hormones.
Therefore, the correct answer is Androgens (C) as they are the male sex hormones responsible for the development and maintenance of male characteristics.

An impairment affecting synthesis or release of ADH results in a diminished ability of the kidney to conserve water leading to water loss and dehydration. This condition is known as Diabetes Insipidus.

The endoderm gives rise to the epithelium of the pharynx, including the eustachian tube, the tonsils, the thyroid gland, parathyroid glands, and thymus gland; the larynx, trachea, and lungs; the gastrointestinal tract (except mouth and anus), the urinary bladder, the vagina (in females) and the urethra. The adrenal glands develop from two separate embryological tissues; the neural crest ectoderm and the intermediate mesoderm.

Gastrin acts on the gastric glands and stimulates the secretion of hydrochloric acid and pepsinogen.

• Endocrine glands lack ducts and are hence, known as ductless glands.
• Their secretions are called hormones.
• As these glands do not have ducts, therefore they release their secretions directly into the bloodstream.

In females, LH induces ovulation of fully mature follicles (graafian follicles) and maintains the corpus luteum, formed from the remnants of the graafian follicles after ovulation.

Thymosins play a major role in the differentiation of T-lymphocytes, which provide cell-mediated immunity, and also promote production of antibodies to provide humoral immunity.

• The pituitary gland is located in a bony cavity called sella tursica and is attached to hypothalamus by a stalk. 
• In females, it stimulates a vigorous contraction of uterus at the time of child birth, and milk ejection from the mammary gland.
• The pineal gland is located on the dorsal side of forebrain.
• After ovulation, the ruptured follicle is converted to a structure called corpus luteum, which secretes mainly progesterone.

Androgens stimulate the growth of facial and axillary hair.