Answer:
The movement of substances may occur across a semi‐permeable membrane (such as the plasma membrane). A semi‐permeable membrane allows some substances to pass through, but not others.
Explanation:
Answer:
Infectious diseases are commonly transmitted through direct person-to-person contact.
The main four pathogens are virus, bacteria, protists and fungi.
Bacteria, fungi and protists can reproduce wherever the conditions are warm, with plenty of moisture, nutrients, and space. Viruses can only reproduce by invading living cells.