Assistant Laboratory Animal Technician Exam 2026 - Complete Practice Test Guide

The nutrient that primarily functions to transport oxygen in the blood is iron. Iron is a critical component of hemoglobin, a protein found in red blood cells. Hemoglobin binds to oxygen in the lungs and carries it throughout the body to tissues and organs, where it is essential for cellular function and energy production. Without adequate iron in the diet, the body cannot produce enough healthy red blood cells, leading to reduced oxygen transport and potential health issues such as anemia.

Calcium, potassium, and sodium each play important roles in the body but do not directly transport oxygen. Calcium is primarily involved in bone health, muscle function, and nerve signaling. Potassium is essential for maintaining fluid balance, nerve transmission, and muscle contractions. Sodium helps regulate fluid balance and is involved in nerve function as well. However, none of these nutrients carry oxygen in the blood like iron does.