Answer:
A
Explanation:
It kinda tells you in the question by talking about salt in water.
Answer:
The plants may make toxins for human consumption.
Explanation:
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.
Hemoglobin is a special protein in the blood that captures and carries oxygen.
