Question

use the drop-down menus to determine whether the following barriers are physical, chemical, or biological. lysozyme skin phagocytes langerhans cells acid and oil secretions sneezing or coughing

Explanation:

• Lysozyme: Enzyme (protein) with antibacterial properties, part of chemical defense (breaks down bacterial cell walls). So chemical.
• Skin: Physical barrier (prevents pathogen entry via its structure). So physical.
• Phagocytes: Cells (like macrophages) that engulf pathogens, biological (cellular defense). So biological.
• Langerhans cells: Immune cells in skin, biological (part of immune system). So biological.
• Acid and oil secretions: Chemicals (e.g., skin's acidic pH, sebum) that inhibit pathogens, chemical.
• Sneezing or coughing: Physical action to expel pathogens, physical.

Answer:

• lysozyme: chemical
• skin: physical
• phagocytes: biological
• Langerhans cells: biological
• acid and oil secretions: chemical
• sneezing or coughing: physical