+
Red Blood Cells

Red Blood Cells

Description:

This lesson will examine the structure and function of red blood cells as well as examine how new red blood cells are made.

(more)
See More
Try a College Course Free

Sophia’s self-paced online courses are a great way to save time and money as you earn credits eligible for transfer to over 2,000 colleges and universities.*

Begin Free Trial
No credit card required

25 Sophia partners guarantee credit transfer.

221 Institutions have accepted or given pre-approval for credit transfer.

* The American Council on Education's College Credit Recommendation Service (ACE Credit®) has evaluated and recommended college credit for 20 of Sophia’s online courses. More than 2,000 colleges and universities consider ACE CREDIT recommendations in determining the applicability to their course and degree programs.

Tutorial

What's Covered

This lesson will cover red blood cells by looking at

  1. Structure and Function
  2. Production

1.Structure and Function

Red blood cells are also known as erythrocytes, and they make up about 45% of total blood volume. Their main role is to carry oxygen to cells and to carry carbon dioxide away. They are shaped like a disk with a little indentation in the middle of it; the shape of a red blood cell is important to its function.

redbloodcell (2).jpg

Term to Know

    • Red Blood Cells
    • Cells found in the blood that carry oxygen and carbon dioxide.
    • Erythrocytes
    • Another word for red blood cells.

An important component of red blood cells is a protein called hemoglobin, which gives the red blood cell its color. It allows the red blood cells to carry oxygen to cells and tissues. Maintaining a stable count is important for homeostasis; we need to have this stable red blood cell count in order to ensure that our cells and our tissues are getting the oxygen that they need.

Some facts about red blood cells:

  • The lifespan of a red blood cell is about 120 days. After that, the cell will die and the different parts can be recycled throughout the body.
  • A cell count is the number of cells in a microliter of blood. So this varies a little bit from person to person, depending on the person's size and whether they're a male or female and whatnot, but the average cell count of a red blood cell is between 4.8 to 5.4 million.

Term to Know

    • Cell Count
    • The number of red blood cells in a microliter of blood.

2. Production

Production of red blood cells is an important process for our body; this process starts with the kidneys. The kidneys play a large role in filtering blood, and, as blood is being filtered, they help to monitor oxygen levels in the blood. If the kidneys detect a decrease in oxygen levels, they are going to create and secrete a hormone called erythropoietin, abbreviated as EPO. EPO will then stimulate bone marrow to produce new red blood cells.

Term to Know

    • Erythropoietin
    • A hormone secreted by the kidneys when oxygen levels in blood are too low to stimulate bone marrow to produce more red blood cells.

redbloodcell (3).jpg

This is an example of a negative feedback loop, because a change was detected and then reversed to bring the body back to a homeostatic level.

Summary

The structure of a red blood cell is that of a disk with a indentation in the middle. It contains hemoglobin, which gives the cell its red color. Its function is to carry oxygen to the cells of the body, and carry away carbon dioxide. Hemoglobin is the protein that allows red blood cells to carry oxygen. Red blood cells are produced when the kidneys detect low oxygen levels in the blood. They create and secrete a hormone called erythropoietin, which in turn signals bone marrow to produce more red blood cells.

Keep up the learning and have a great day!

Source: SOURCE: THIS WORK IS ADAPTED FROM SOPHIA AUTHOR AMANDA SODERLIND

TERMS TO KNOW
  • Red Blood Cells

    Cells found in the blood that carry oxygen and carbon dioxide.

  • Erythrocytes

    Another word for red blood cells.

  • Cell Count

    The number of red blood cells in a microliter of blood.

  • Erythropoietin

    A hormone secreted by the kidneys when oxygen levels in blood are too low to stimulate bone marrow to produce more red blood cells.