Answer:
here.
Explanation:
Due to the prevalence of malaria in Africa, the allele for sickle cell anemia (HbS) provides a selective advantage. That's why it remains in the population.
A normal African person (HbAHbA), with normal haemoglobin, will not die of anemia, but will die of malaria.
An African person with sickle cell anemia (HbSHbS), with abnormal haemoglobin, will die of anemia.
A heterozygous African person (HbAHbS), with half of his red blood cells (RBCs) being normal and the other half being sickle-shaped, will neither die from anemia, nor malaria since the plasmodium will be incapable of completing its life cycle in the abnormal RBCs.
Thus heterozygous African people will grow, reproduce and pass on the HbS allele to the next generations.
Cutaneous membrane also known as the skin
I can help you with that, hfnj2013! :3 The cytoskeleton is responsible for the support structure and movement of cells in your body. Hope that helps!!! XP
according to sciencethreads.com
it states the following pros and advantages of fossil fuels..
<em><u>1)Fossil fuels have a very high calorific value. </u></em>
<em><u>2)the energy produced by fossil fuels is greater than that produced by an equivalent amount of other energy resource.</u></em>
<em><u>3)Systems are set up to process and utilize oil and gas
</u></em>
<em><u>4)Widely available around the globe
</u></em>
<em><u>5)low cost per unit energy
</u></em>
<em><u>6)Refineries, transportation, and plastics all rely heavily on oil and gas
</u></em>
<em><u>7)High energy output
</u></em>
<em><u>8)Employs millions of people globally
</u></em>
<em><u>9)The primary source of all plastics</u></em>
hope this helps :)
Answer:
The correct option is A. Polycythemia Vera
Explanation:
Polycythemia vera is a myeloproliferative disorder of bone marrow hematopoietic cells that causes excessive production of all types of blood cells.
Primary erythrocytosis occurs as a result of polycythemia vera, in this myeloproliferative disorder the bone marrow produces too many red blood cells along with excessive amounts of white blood cells and platelets. Bone marrow under normal conditions produces blood cells and contains the precursor cells of the three series: red blood cells, white blood cells or leukocytes and platelets or thrombocytes, this disorder is characterized by excessive or uncontrolled proliferation or growth of these cells. The increased production of red blood cells or erythrocytes is called erythrocytosis.
