All of the following are true of RBCs except:
a. Biconcave disc shape
b. Life span of approximately 120 days
c. Contain hemoglobin
d. Contain nuclei

Verified step by step guidance

1. Step 1: Understand the structure and function of red blood cells (RBCs). RBCs are specialized cells primarily responsible for transporting oxygen throughout the body using hemoglobin.
2. Step 2: Recall that RBCs have a distinctive biconcave disc shape, which increases their surface area for gas exchange and allows flexibility to pass through narrow capillaries.
3. Step 3: Remember that mature RBCs do not contain nuclei. This absence allows more room for hemoglobin, maximizing oxygen-carrying capacity.
4. Step 4: Note that RBCs have a typical lifespan of about 120 days, after which they are removed from circulation and recycled by the spleen and liver.
5. Step 5: Based on these facts, identify which statement is false by comparing each option to the known characteristics of RBCs, focusing especially on the presence or absence of nuclei.

Key Concepts

Red Blood Cell (RBC) Structure

RBCs have a distinctive biconcave disc shape that increases their surface area for efficient gas exchange. This shape also allows them to deform as they pass through narrow capillaries. Unlike many other cells, mature RBCs lack a nucleus to maximize space for hemoglobin.

RBC Lifespan

The average lifespan of a red blood cell is about 120 days. After this period, RBCs are typically removed from circulation by the spleen and liver. This lifespan is important for maintaining healthy oxygen transport and for the turnover of old or damaged cells.

Hemoglobin Function in RBCs

Hemoglobin is the iron-containing protein in RBCs responsible for binding and transporting oxygen from the lungs to tissues. It also carries carbon dioxide back to the lungs for exhalation. The presence of hemoglobin is essential for the primary function of RBCs in gas exchange.