Which part of the human digestive tract is primarily responsible for the absorption of digested food? MCQ with Answer and Explanation

Explanation:
Platelets (thrombocytes) are small, anucleate cell fragments that adhere to the site of injury, release clotting factors, and aggregate to form a platelet plug, initiating the coagulation cascade. RBCs transport oxygen, WBCs defend against infection, and plasma proteins like albumin maintain osmotic balance. Clotting factors are also present in plasma, but platelets are the primary cellular component.

Explanation:
Chlorophyll, the primary photosynthetic pigment, is embedded in the thylakoid membranes within chloroplasts. These membranes contain photosystems I and II, where light-dependent reactions occur. The stroma of the chloroplast houses the Calvin cycle enzymes. Chlorophyll absorbs mainly blue and red light, reflecting green, giving leaves their color.

Explanation:
Thyroid Stimulating Hormone (TSH), also known as thyrotropin, is a glycoprotein hormone secreted by the thyrotroph cells of the anterior pituitary gland. Its primary and specific target is the thyroid gland. TSH binds to receptors on the thyroid follicular cells, stimulating all aspects of their function: the uptake of iodine, the synthesis of the thyroid hormones thyroxine (T4) and triiodothyronine (T3), and the release of these hormones into the bloodstream. TSH secretion is regulated by Thyrotropin-Releasing Hormone (TRH) from the hypothalamus and by negative feedback from T3 and T4.