Why is there variation in skin color among modern humans?
A. People have different numbers of melanocytes.
B. People have a different distribution of carotene in their skin.
C. People have a different distribution of melanin in their epidermis.
D. People are exposed to different chemicals over their lifetime.
E. People have different hemoglobin in vessels close to their skin.
C. People have a different distribution of melanin in their epidermis.
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Which membrane transport process(es) is/are abnormal in people with cystic fibrosis? What is the consequence of the abnormal transport? Which organ systems are affected? How is this disease treated? How long do cystic fibrosis patients normally live? What are some of the possible causes of death related to this disease? What is the cause of cystic fibrosis?
You are walking to school one day when you notice an alien spaceship that has crashed in a nearby field. You and some other physiology students collect samples from the beings inside of the spaceship. First, you collect a liquid sample of what appears to be alien blood so that you can test for the concentration of solutes inside the alien blood cells. You then extract some of these cells, place them in various concentrations of glucose in water, then look at them under the microscope. Below is what happens to the cells when they are placed in various concentrations of glucose:
Which of the following is not considered an abdominopelvic region?
A) right hypochondriac B) right inguinal region C) left lumbar D) left hypochondriac E) upper right
The interconnecting bony struts of spongy bone are known as ________
A) Haversian canals B) perforating canals C) lacunae D) trabeculae
Which ventricle is located in the brainstem?
A. Third B. Lateral C. Fourth D. Second