The correct answer is the environment.
<span>Non-infectious diseases are those that are not contagious meaning that they can't be spread from one person to another (no vector for them to move). Non-infectious diseases are caused by factors, like genetics, environment, and behaviour. Some can be prevented, while others don’t. Examples of this type of diseases are autoimmune<span> diseases, cancers, allergies, sleep disorders, diabetes…</span></span>
Penetration of the egg' zona pellucida by the sperm cell is a process driven by hydrolytic enzymes.
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The critical step in fertilization is binding between sperm receptors and glycoproteins on the zona pellucida. This is the trigger for the acrosome reaction which includes an influx of CA and a rise in pH and cAMP levels within the sperm head. As a result, the plasma membrane of the sperm fuses with the outer acrosomal membrane and the exocytosis of the acrosomal<span> vesicle occurs. Components of the acrosome, like hydrolytic enzymes, are released and they degrade the <span>zona pellucida allowing</span> the sperm to move </span>inside.</span>
Metabolism is a set of chemical reactions happening within an organism. These reactions are necessary to maintain the living state of cells, allowing them to reproduce, grow, and respond to environment.
