Endocrine System (Exam Mode)

Estrogen is a hormone that plays various roles in the body. It is responsible for causing breast growth, inhibiting FSH (follicle-stimulating hormone), and increasing follicle development. However, it does not have a function in decreasing overall transport proteins. Transport proteins are essential for the movement of molecules and substances in the body, and estrogen does not play a role in their decrease.

Vasopressin is not an anterior pituitary gland secretion. The anterior pituitary gland secretes TSH (thyroid-stimulating hormone), GH (growth hormone), and prolactin. Vasopressin, also known as antidiuretic hormone (ADH), is produced by the hypothalamus and released by the posterior pituitary gland. It plays a role in regulating water balance and blood pressure by controlling the reabsorption of water in the kidneys.

Angiotensin I is converted into Angiotensin II by ACE (Angiotensin Converting Enzyme). ACE is an enzyme that is primarily found in the lungs. It plays a crucial role in the renin-angiotensin-aldosterone system, which regulates blood pressure and fluid balance in the body. ACE catalyzes the conversion of Angiotensin I to Angiotensin II by removing two amino acids from Angiotensin I. Angiotensin II is a potent vasoconstrictor and also stimulates the release of aldosterone, which promotes sodium and water reabsorption, leading to increased blood pressure.

During phase 3 of the myocardial action potential, the ion that is moving the most is K+. This is because phase 3 is the repolarization phase, where the cell is returning to its resting state. K+ channels open, allowing K+ ions to move out of the cell, which helps to restore the negative charge inside the cell. This movement of K+ ions is responsible for the repolarization of the cell membrane.

Hypokalemia is a condition characterized by low levels of potassium in the blood. The U wave is an additional wave that appears after the T wave in an electrocardiogram (ECG). It is typically small and can be seen in some individuals, but it becomes more prominent in the presence of hypokalemia. Therefore, the U wave is associated with hypokalemia during an ECG.

Decreased capillary output is not a cause of peripheral edema because peripheral edema is the accumulation of fluid in the tissues due to increased capillary permeability or reduced levels of plasma proteins. Heart failure can also cause peripheral edema by impairing the heart's ability to pump blood effectively. However, decreased capillary output refers to a decrease in blood flow through the capillaries, which would not directly lead to fluid accumulation in the tissues.

An S3 heart sound is often associated with congestive heart failure (CHF). This extra heart sound occurs due to the rapid filling of the ventricles during the early phase of diastole. In CHF, the heart becomes weak and unable to pump blood efficiently, leading to fluid accumulation in the lungs and other parts of the body. This causes the ventricles to stretch and results in the S3 sound. Therefore, CHF is the most likely condition associated with an S3 heart sound.

Angiotensin II is a hormone that is involved in regulating blood pressure. It causes vasoconstriction, which means it narrows the blood vessels and increases blood pressure. Therefore, it does not cause vasodilation, which is the opposite effect of widening the blood vessels and decreasing blood pressure.

The ejection fraction is a measure of the percentage of blood that is pumped out of the heart with each contraction. It is calculated by dividing the stroke volume (the amount of blood pumped out of the heart with each contraction) by the end-diastolic volume (the amount of blood in the heart at the end of relaxation). Therefore, the correct answer is SV/EDV.

Thyroid Hormone T3 is known to have multiple functions in the body, including stimulating bone development and growth, creating beta-adrenergic responses, and causing brain development. However, it does not have the function of decreasing calcium re-absorption.

Bradykinin is a peptide that is involved in various physiological processes. It is known to cause elevated capillary permeability, which leads to increased leakage of fluid and proteins from blood vessels into surrounding tissues. It also causes elevated pain levels by sensitizing pain receptors. Additionally, bradykinin is responsible for elevated vasodilation response, leading to the relaxation and widening of blood vessels. However, bradykinin does not have an effect on elevated prothrombin secretion, which is the process of producing a clotting protein involved in blood clot formation.

Mean arterial pressure is a measure of the average pressure in the arteries during a cardiac cycle. It is influenced by two factors: total peripheral resistance (TPR) and cardiac output (CO). TPR is the resistance to blood flow in the systemic circulation, while CO is the volume of blood pumped by the heart per minute. The product of TPR and CO gives the mean arterial pressure. This means that an increase in either TPR or CO will result in an increase in mean arterial pressure, while a decrease in either TPR or CO will result in a decrease in mean arterial pressure.

PAH (para-aminohippuric acid) is a substance that is commonly used to measure renal plasma flow. It is secreted in the proximal tubule of the nephron. The proximal tubule is responsible for reabsorbing most of the filtered substances, but it also secretes certain substances, including PAH. This secretion process helps to eliminate PAH from the body and plays a role in the regulation of renal plasma flow. Therefore, the correct answer is the proximal tubule.

Hypercalcemia is a condition characterized by high levels of calcium in the blood. It can be caused by various factors, including Paget's disease, sarcoidosis, and malignancy. However, aldosterone, a hormone produced by the adrenal glands, is not associated with hypercalcemia. Aldosterone primarily regulates salt and water balance in the body and does not directly affect calcium levels. Therefore, it is not linked with hypercalcemia.

The source cell for the secretion of Pepsinogen is the Chief cell. Pepsinogen is an inactive form of the enzyme pepsin, which is responsible for breaking down proteins in the stomach. Chief cells are found in the gastric glands of the stomach and they secrete pepsinogen into the stomach lumen. Once pepsinogen comes into contact with the acidic environment of the stomach, it is converted into active pepsin, which aids in digestion.

Acetylcholine is the primary activator of zymogen secretion. Zymogens are inactive enzymes that are converted into their active form to carry out various physiological processes. Acetylcholine, a neurotransmitter, stimulates the release of zymogens from the pancreas and salivary glands. It binds to specific receptors on the cells, triggering a signaling cascade that ultimately leads to the secretion of zymogens. This activation of zymogen secretion by acetylcholine is crucial for proper digestion and the breakdown of food in the gastrointestinal tract.

A 2nd degree (Mobitz Type 1) AV block is typically characterized by nonsequential conduction, where there is a P wave without a corresponding QRS complex. It is usually asymptomatic and is associated with an increased PR segment/interval. The statement "70% Fatal" is not generally associated with a 2nd degree (Mobitz Type 1) AV block.

ACTH (adrenocorticotropic hormone) does not require the precursor progesterone. ACTH is produced by the anterior pituitary gland and stimulates the production of cortisol in the adrenal glands. Cortisol, testosterone, and aldosterone are all steroid hormones that are derived from progesterone. However, ACTH itself does not require progesterone as a precursor for its synthesis.

Atrial natriuretic peptide (ANP) is a hormone that is released by the atria of the heart in response to increased atrial pressure. ANP acts on the kidneys to decrease sodium reabsorption, leading to increased excretion of sodium in the urine. This helps to decrease blood volume and blood pressure. Therefore, ANP causes increased atrial pressure and decreases sodium reabsorption in the kidneys.

Progesterone is a hormone that plays a crucial role in the female reproductive system. It is responsible for causing increased body temperature and smooth muscle relaxation, which are important for maintaining pregnancy. Progesterone also promotes increased spiral artery growth, which is necessary for adequate blood supply to the uterus during pregnancy. However, progesterone does not cause activation of FSH (follicle-stimulating hormone). FSH is a hormone that is responsible for stimulating the growth and development of follicles in the ovaries.