Why are red blood cells macrocytic in pernicious anemia? a. production of hemoglobin is impaired, so the erythrocytes are more pale than usual. b. erythrocytes are produced more rapidly, so the erythrocytes are smaller than usual. c. normal cell growth but slower cell division in the bone marrow makes the erythrocytes larger than usual. d. lack of erythropoietin causes sluggish activity of bone marrow and makes the erythrocytes darker than usual.

The tasmanian devil, a marsupial carnivore, is facing extinction due to devil facial tumor disease (dftd) which causes bulging cancerous lumps and lesions to erupt around the face and neck — often causing enough deformation to make seeing or eating difficult. dftd has evolved into a contagious cancer, a trait that is unique among cancers. devil mating behavior involves biting around the head and neck, allowing cells from one individual — especially cells from the crumbly dftd tumors — to be transferred to the wounds or face of a new individual. this marsupial was once found across australia, but sea levels rose, isolating the tasmanian population, while the australian population went extinct. what would be an outcome of genetic isolation that is likely to have impacted the spread of dftd? a) reduced territory puts diseased individuals in greater contact with non-diseased ones. b) inbreeding results in less variation in facial features so the cancer is generally fatal. c) genetic isolation has made it difficult for scientists to develop a vaccine against dftd. d) the lack of genetic variation in the immune system of tasmanian devils minimizes resistance to the disease.

Connection compare and contrast genetic engineering to the process of natural selection. select all statements that are true.

Common symptoms of an iron-defiency anemia include muscle weakness shortness of breath and lightheadedness why does iron deficiency causes these symptoms