What have four eyes but cannot see?

Male 12 years I used to have frequent erections now I do not is something wrong? Why does a warm muscle contract more forcefully than a cool one? What are the 5 lymphatic organs? How can you naturally enlarge your breasts? What is ranidaphobia? When can psychologist use deception? Can you get chlamydia during your period? What is the definition of Crohn disease? If you do twenty push ups per day how many days till you get stronger? What does ischemia or LV overload mean in an ekg? What plays a central role in the circulatory system and what does it consist of? What advice would you give to an obese smoker who suffers from hypertension? What is the importance of urinary bladder? Is peptobismol safe to take with elevated liver enzymes? Why sleepy when you lie down? What is mild hypertrophic degenerative? What is weakened and allows the host to fight disease? What does your body do if you receive a blood transfusion with a different type of marker? What are the branching tubes from the trachea called? What happened to those who were sent to quarantine of the black death?