Multiple Choice
Which of the following is not a physical barrier against infection?
142
views
21. The Immune System
Physical Barriers in First-Line Defenses: Skin
Struggling with Anatomy & Physiology?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Examples of 1st line defenses to infection which are components of the innate immune system include all of the following except?
A
Unbroken skin.
B
Phagocytosis of a pathogen by an immune cell.
C
Digestive enzymes in saliva.
D
Destructive acids in gastric juices.
E
Naturally occurring human microbiome.
Verified step by step guidance1
Understand the concept of the innate immune system, which provides the first line of defense against pathogens. It includes physical barriers, chemical barriers, and biological components.
Identify the physical barriers: Unbroken skin acts as a physical barrier preventing pathogens from entering the body.
Recognize the chemical barriers: Digestive enzymes in saliva and destructive acids in gastric juices help neutralize and destroy pathogens.
Consider the biological components: The naturally occurring human microbiome competes with pathogens and prevents their growth.
Phagocytosis is a process where immune cells engulf and destroy pathogens, which is part of the second line of defense, not the first line. Therefore, it is the exception in this list.
1:28mWatch next
Master Physical Barriers with a bite sized video explanation from Bruce Bryan
Start learningRelated Videos
Related Practice
Physical Barriers in First-Line Defenses: Skin practice set
Problem sets built by lead tutorsExpert video explanations