Anatomy & Physiology Part 4: The Immune & Endocrine Systems

An advanced quiz on the body's defense and communication networks.

📖 Core Concepts Review

System	Component	Primary Function	Key Concepts
🛡️ Immune System	Innate vs. Adaptive	Innate: Rapid, non-specific. Adaptive: Slow, specific, memory.	Phagocytes, T-Cells, B-Cells, Antibodies
🧠 Endocrine System	Glands & Hormones	Secrete hormones for chemical signaling.	Pituitary, Thyroid, Pancreas, Adrenals
⚙️ Regulation	Feedback Loops	Maintain homeostasis.	Negative Feedback (most common), Positive Feedback
🔑 Hormone Action	Peptide vs. Steroid	Peptides: Surface receptors. Steroids: Intracellular receptors.	Signal Transduction, Gene Expression

Problem 1: Antigen Presentation

Hard

ImmunologyMHCT-Cells

An antigen-presenting cell (APC) such as a macrophage engulfs a bacterium and presents a piece of it on its surface. Which class of Major Histocompatibility Complex (MHC) molecule is used, and which cell type does it present to?

MHC Class I; presents to Cytotoxic T-cells (CD8+).

MHC Class I; presents to Helper T-cells (CD4+).

MHC Class II; presents to Cytotoxic T-cells (CD8+).

MHC Class II; presents to Helper T-cells (CD4+).