Identify the six structures that are vital to fetal circulation but cease to function at birth, and describe what becomes of these structures
What will be an ideal response?
The six structures vital to fetal circulation are two umbilical arteries, one umbilical vein, the ductus venosus, the foramen ovale, and the ductus arteriosus. After birth, the foramen ovale closes and persists as the fossa ovalis, a shallow depression; the ductus arteriosus persists as the ligamentum arteriosum, a fibrous cord; and the umbilical vessels and ductus venosus persist throughout life as fibrous cords.
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_________. Fill in the blank(s) with correct word
Read the two statements and use the following key to choose the best answer.A. The first item is greater than the second item.B. The first item is less than the second item.C. The first item is equal or nearly equal to the second item.(1) The rate of erythropoiesis when erythropoietin is present(2) The rate of erythropoiesis when erythropoietin is absent
Fill in the blank(s) with the appropriate word(s).
Why is basal cell carcinoma considered less dangerous than malignant melanoma?
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Which of these animals has an open circulatory system?
a. lobster b. shark c. sea anenome d. sponge e. nematode