1.Red blood cells carry nutrition and oxygen through the capillaries to the tissues. 2. Oxygen is inhaled from the atmosphere to alveoli. 3. Oxygen diffuses into the pulmonary capillaries carried by hemoglobin through the systemic capillaries to the cells. 4. Hemoglobin gives up oxygen and picks up carbon dioxide by diffusion.
Pre-menstrual symptoms (PMS) are the symptoms that a woman may experience one or two weeks before her period begins. PMS is more common in women of age group 30 to 40. About 80% of women experience mild or severe premenstrual symptoms before each period.
Early Pregnancy symptoms Before the Missed Period. It is worth noting here that this has not been extensively studied medically. An earlier study found that women began reporting symptoms as early as Day 27 of their cycle and that 50% of pregnancy women had symptoms by Day 36.