Even though sickle-cell anemia is usually fatal to homozygous individuals (aa), the disease persists because:

When amino acids are combined together, they make up:

Match the lymphocyte with its function:

Which of the following is NOT a function of skeletal muscle? 

The pancreas is considered a heterocrine gland (both endocrine and exocrine). Of the following, choose the option that matches the function with correct endocrine or exocrine part of the pancreas. 

Which of the following leukocytes is the least common? 

True or false: 90% of nutrient absorption happens in the ileum of the small intestine.

Which of the following organs are considered retroperitoneal rather than intraperitoneal? (choose all that apply). 

90% of all nutrient absorption happens in the small intestine. Which region is responsible for most of this absorption? 

Two weeks following a hiking trip in which several ticks were noticed and numerous mosquitoes were biting, a 25-year-old man notices a rash shaped like a red ring on the back of his thigh. He was not concerned because he had no other symptoms. Three months later he noticed significant pain in his elbows and his knees. What is the most likely cause of his illness?