(2) The peel of No.4 tomato was cut open, which lost its protective function and came into contact with decaying substances. The experimental result was severe decay.
(3) The skin can prevent germs from invading the human body, and it belongs to the first line of defense of the human body. Skin acts on all pathogens and belongs to non-specific immunity.
(4) When the pathogen enters the human body, it will stimulate lymphocytes to produce a special protein called antibody, which can help the human body to remove or kill the pathogen that has entered the human body; When the disease is cured, the antibody remains in the human body.
(5) The source of infection refers to people and animals that can spread pathogens, and the source of infection can only be people or animals. Transmission route refers to the way that pathogens leave the source of infection and reach healthy people. Susceptible population refers to people who are susceptible to certain infectious diseases due to lack of immunity. People with rabies belong to the source of infection.
So the answer is: (1) control;
(2) serious decay;
(3) nonspecific;
(4) antibodies;
(5) the source of infection.