I wanna say A. Desert
Hope this helps!!
Answer:
Mechanical barriers — which include the skin , mucous membranes , and fluids such as tears and urine — physically block pathogens from entering the body. Chemical barriers — such as enzymes in sweat , saliva , and semen — kill pathogens on body surfaces.
Answer:
D, think of chemical changes. When iron rusts it is chemically changed. The other answers are a change in form or a property of iron.
Edema is a condition of abnormally large fluid volume in the circulatory system or in tissues between the body's cells(interstitial <span>spaces).</span>
Yes we did we had microbes before we were born