Which of the following heart valves lies between the left atrium and left ventricle and prevents the regurgitation of blood from the ventricle back into the atrium?

Kidneys are not part of the lymphatic system.

The lymphatic system is a network of vessels and organs that drain excess fluid from the tissues, transport fats and immune cells, and protect the body from infections.

Kidneys are part of the urinary system, which filters blood, regulates fluid and electrolyte balance, and produces urine.

Choice A is wrong because kidneys do not have a direct connection to the lymphatic system.

Although kidneys have lymphatic vessels in their cortex, they do not originate from the lymphatic system.

Kidneys receive blood from the renal arteries and return it to the renal veins.

The lymphatic vessels in the kidney cortex drain interstitial fluid and immune cells from the kidney tissue to the regional lymph nodes.

Some additional sentences are:

Choice B is right because kidneys are part of the urinary system, not the lymphatic system.

The urinary system and the lymphatic system have different functions and structures in the body.

Normal ranges for kidney function tests include blood urea nitrogen (BUN) of 7 to 20 mg/dL, serum creatinine of 0.6 to 1.2 mg/dL, and glomerular filtration rate (GFR) of more than 90 mL/min/1.73 m.

Normal ranges for lymphatic system tests include white blood cell (WBC) count of 4,000 to 11,000 cells per microliter, lymphocyte count of 1,000 to 4,800 cells per microliter, and immunoglobulin levels of IgG (700 to 1,600 mg/dL), IgA (70 to 400 mg/dL), IgM (40 to 230

mg/dL), IgE (0 to 100 IU/mL), and IgD (0.5 to 5 mg/dL).

The hypothalamus is the part of the brain that produces hormones that control the pituitary gland.
The pituitary gland then releases hormones that target other endocrine glands, such as the thyroid, adrenal, and gonads.
Therefore, the hypothalamus is the source of releasing hormones for target cells in the anterior pituitary gland.
Choice A is wrong because the anterior pituitary gland does not produce releasing hormones, but responds to them by secreting other hormones.
Choice C is wrong because the thyroid gland does not produce releasing hormones, but responds to them by secreting thyroid hormones.
Choice D is wrong because the posterior pituitary gland does not produce releasing hormones, but stores and releases hormones made by the hypothalamus, such as oxytocin and antidiuretic hormone.