A biological system is a complex network of biologically relevant entities. ... Examples of biological systems at the macro scale are populations of organisms. On the organ and tissue scale in mammals and other animals, examples include the circulatory system, the respiratory system, and the nervous system. source: google
The correct answer is the final option - sickle cell disease and malaria are both potentially lethal diseases.
The other options are incorrect because sickle cell disease is an inherited disease, but malaria is not - it is an infectious disease. However, both of these disease are quite dangerous, and may have severe consequences (such as death) if they are not properly treated.
Answer:
In a comparison of birds and mammals, the condition of having four limbs is a shared ancestral character
the three accessory glands: the seminal vessicles, the bulbourrethhral gland, and the prostate
I'm not entirely sure if I'm correct with this, but I'll try...
Adolescence has to do something with mentality, or how the brain works. It occurs from things like family issues, depression, anxiety, substance abuse, (substance: drugs) sexual abuse, violence, things like that. Men are more likely to suffer from it (I think).
Welp, I've thrown in my two cents, sorry if It's incorrect, at least I tried, lol.