Expected Learning: To develop a comprehensive understanding of the first line of defence in the immune system. First Line of Defence. By Eden Aspinall and Theresa Hudson. Physical Barriers: Animals. Integumentary system (skin) is the main barrier, preventing pathogens from entering
By Eden Aspinall and Theresa Hudson
They actually don’t!!
Many plants are resistant to pathogens and have several characteristics that protect them from infection from things such as insects and nematode worms.