Nursing Student
New Grad

07.01 Blood Plasma

This lesson is part of the Pre-Nursing Academy. Start a trial to view the entire video.


  1. Overall components of blood
    1. Plasma – fluid (55-57%)
      1. 92% water
    2. Formed elements (43-45%)
      1. White Blood cells (leukocytes)
      2. Red Blood cells (erythrocytes)
      3. Platelets (thrombocytes)

Nursing Points


    1. Functions
      1. Suspension of cells, substances in blood
      2. Transport medium for nutrients, chemicals
    2. Soluble components of plasma (dissolved in the water)
      1. Plasma Proteins
        1. Types
          1. Albumin
            1. Smallest
            2. Most common (60%)
          2. Globulins
            1. Alpha-1
            2. Alpha-2
            3. Beta
            4. Gamma (antibodies)
          3. Prothrombin & Fibrinogen
            1. Clotting
        2.  Functions
          1. Maintain osmotic balance (see Fluid Pressures lesson)
            1. Hydrostatic pressure
            2. Colloid Osmotic pressure (Oncotic pressure)
          2. pH regulation
            1. Proteins react with hydrogen ions
            2. Normal pH = 7.35-7.45
          3. Lipid transport
            1. Globulins attach to fat-soluble substances
            2. Alpha-1, Alpha-2, Beta
      2. Non-protein nitrogenous substances (NPN)
        1. Waste products (liver → blood → kidneys → out)
          1. Urea
          2. Uric acid
          3. Creatinine
      3. Organic nutrients
        1. Glucose
        2. Amino acids
        3. Lipids (fat-soluble substances, attached to globulins)
          1. Cholesterol
          2. Fatty acids
          3. Triglycerides
          4. Steroid hormones
          5. Vitamins A, D, E, & K
      4. Hormones and water soluble vitamins
        1. Dissolved in water in plasma for transport
      5. Electrolytes
        1. Cations (highest to lowest)
          1. Sodium
          2. Potassium
          3. Calcium
          4. Magnesium
        2. Anions (highest to lowest)
          1. Chloride
          2. Bicarbonate
          3. Phosphate
        3. Functions
          1. Assist in maintaining osmotic balance and pH
      6. Gases (highest to lowest)
        1. Nitrogen
        2. Oxygen
        3. Carbon Dioxide











Create Your Account

Get unlimited access to lessons and study tools

Get Started

Video Transcript

In this lesson, we are going to take a look at blood plasma.

I like to think of blood as being this soup with all of these different components in it. Now plasma is like the broth which is the majority of the liquid part. So in blood plasma takes up about 55% of the total blood volume and is made up of about 92% water. Inside the plasma there are different types of formed elements which are things like red blood cells, white blood cells, and platelets. These formed elements take up 43 to 45% of the total blood volume.

Now there’s some really important functions of the plasma, and that’s that it is a suspension of cells and other substances in the blood which we’re going to talk about in a minute. The other thing is that it serves as a transport medium for different types of nutrients and other chemicals.
Also, in plasma there are a bunch of different components but the first thing we’re going to look at are the different types of proteins. There are several different types of plasma proteins with albumin being the most abundant which takes up about 60%. It’s also the smallest plasma protein.

There’s also another type of plasma protein called globulins. There are alpha 1, Alpha 2, beta, and gamma globulins. Some gamma globulins serve as antibodies and are the most significant. The big thing to know about the gamma globulins is that they are not water soluble, and since the majority of plasma is water, they don’t dissolve. So they function in transporting other components, which I’ll talk about in a minute.

There are other types of plasma proteins like prothrombin and fibrinogen which are clotting plasma proteins. These proteins are responsible for going to sites where there is bleeding, and they help to stop bleeding.

There are some really important functions of these plasma proteins. One of the most important functions of plasma protein is that they maintain the pressure balance within all fluids. They do this with oncotic and hydrostatic pressure, which are pulling and pushing pressures. There’s a great lesson on fluid pressures, and I encourage you to check that out. The other thing the plasma proteins do is that they help to regulate PH because the proteins react with hydrogen ions in the plasma. One final thing that they do is that they’re responsible for lipid transport. Globulins will attach two different types of fat soluble substances, like fat soluble vitamins, and it will help to transport them to where they need to go.

The plasma is also responsible for containing different types of non protein substances and organic nutrients.

Plasma contains something called non-protein nitrogenous substances, or npn. These are virtually waste products. So these are things like urea, uric acid, and creatinine, and these are transported as a result of the body filtering. So the liver will filter the blood, and the kidneys will the remaining plasma and kick it out of urine.

The other thing that the plasma holds are different types of organic nutrients. So these are things like glucose, amino acids, lipids, and different types of fat soluble vitamins and steroid hormones. The fat soluble vitamins are going to be vitamins a, d, e, and K. The globulins will also transport different types of fatty acids and triglycerides, and that’s because they’re not water soluble.

The other thing that happens in plasma is the transport of hormones that CAN be dissolved in water. Also, it’s important to know that water soluble vitamins are transported in plasma, so these are the B & C vitamins.

We also want to take a look at electrolytes and gases.

In the plasma. There are several different types of electrolytes that not only are present but play an important role. If you look at the positively charged ions or cations, sodium is the most abundant plasma followed by potassium, calcium, and then magnesium which is the least abundant. In terms of and ions, or negatively charged ions, chloride is the most abundant, followed by bicarbonate and phosphate feed the least of us. They focus in assisting in maintaining osmotic balance and also balancing out the pH of the plasma.

When it comes to gases inside the blood plasma, nitrogen is not only the most abundant, but makes up the majority of the gases in plasma. This is followed by oxygen and carbon dioxide.
Okay, so let’s recap.

Plasma takes up the majority of the blood component, accounting for about 55%.

Also it’s mostly water, with about 92% of the blood plasma consisting of water.

The plasma proteins in the blood plasma are responsible for maintaining osmotic balance and pressure. They do this through hydrostatic and oncotic pressure.

What type of also contains waste, so these are waste products like urea, uric acid and creatinine.

And finally blood plasma is a transport medium. That means that it’s going to transport all of the vitamins, nutrients, hormones, and it’s 3 series of mechanisms. It’s just really important that you understand that blood plasma doesn’t just contain cells, but it also contains all of these other important components.

And that’s it for our lesson on blood plasma. Make sure you check out all the resources attached to this lesson. Now, go out and do your best selves today, and as always, happy nursing.

Read more

Module 0 – Anatomy & Physiology Course Introduction

Module 5 – Sensory System A&P

Module 7 – Hematologic System A&P

Module 8 – Lymphatic System A&P

Customize Your Study

Start a trial to create your first custom study plan now.

Start Trial