The correct answer is: 4) Standing defenses are always present; induced defenses develop in response to a threat
Induced defense is defense that can be changed or invoked when needed. Induced defenses are slow to happen. When invoked, induced defense requires energy but otherwise doesn’t.
Standing defense is always there. It is use, for example when predation is a constant threat.
Answer: Carbon Monoxide is a very harmful and toxic gas which is formed from incomplete combustion of carbon.
Explanation: red blood cells contain haemoglobin ,which are responsible for carrying oxygen into our body system. So oxygen combines with haemagoblin to form oxyhaemogoblin in the red blood cells .
so if a person starts to intake cigarettes which contain high amounts of carbon monoxide ,it reduces oxyhaemogoblin formation because it binds very tightly to the haemogoblin .then carboxyhaemogoblin is formed and its permanent so causing reduction in aerobic respiration, and reduction in oxygen transport and causing damages to heart muscles.
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D. Growth, Metabolism, and Differentiation.