Blood Overview

Blood Overview

Author: Aaron Mullally

- know the basic functions of blood

- know what kind of tissue blood is

- know the difference between formed elements and plasma

- know how much blood the average human contains and what contributes to differences in volumes

This packet introduces some basic concepts about blood

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Blood is a connective tissue that is the major transport medium of the body. Remember that connective tissues are composed of cells and proteins in the extracellular matrix (ECM). When you mix all of these together you get a gel; and this particular gel is connective tissue by properties only, it does not actually directly connect objects together like CT proper.

Blood is composed of two main parts: plasma and formed elements (cells). Blood is 55% plasma and 45% formed elements. Plasma is basically water with organic and inorganic materials dissolved in it. The three types of formed elements are erythrocytes (red blood cells), leukocytes (white blood cells) and platelets (thrombocytes).

The primary function of blood is transportation. Here are a few items that blood transports:

  • gases (oxygen and carbon dioxide)
  • nutrients (glucose, amino acids, lipids)
  • hormones
  • buffers
  • metabolic wastes

Blood also serves as a buffer against changes in pH and also has immune functions with the antibodies and leukocytes that are within it.

Source: Mind of Aaron

Introduction to Blood

Source: Self made

Blood Overview

Source: Self made