Human Anatomy Learning Modules: These learning modules include:
Back & Vetebral Column // Thorax // Abdomen // Pelvis & Perineum // Lower Extremity // Upper Extremity // Head & Neck
This site not only includes helpful skeletal images, but also practice questions for each of the covered regions.
BioDigital Systems: Availble for free (individual) or for a fee (groups/businesses), this interactive system will first require you to sign in via your Facebook or Google account to gain access. Once inside the system, you can zoom and rotate your virtual skeleton. Eleven systems in total are able to view and examine. Note: this site allows you to repeatedly quiz yourself on all eleven systems that are covered within the site.
Anatomy Drill & Practice: This site covers the human body, the chemical, cellular, and tissue levels of organization, the integumentary system, skeletal system, muscular system, nervous system, cardiovascular system, respiratory system, digestive system, excretory system, and reproductive system.
This site not only includes images of and information on the above listed systems, but it also includes interactive drills and practice questions for students. NOTE: Flash required for the quizzes/practice questions.
The AK Lectures are a series of lectures from a (external) educational platform designed to "promote collaboration between our users and help spread knowledge to every part of the world."
These lectures vary in length, and will open in a new window when you click on the provided link.
Introduction to the Cardiovascular System: The cardiovascular system consists of the heart, blood vessels and blood. The heart consists of cardiac muscle that forms a web-like net that contracts upon itself. It consists of two individual pumps that are connected in series with respect to one another. The right pump consists of the right atrium and ventricle while the left pump consists of the left atrium and ventricle. The function of the heart is to keep the blood continuously flowing through our blood vessels. Blood vessels are the conduits that carry the blood and blood is a connective tissue that consists of a multitude of nutrients, water, minerals, salts, proteins, hormones, waste products and other things. Arteries are blood vessels that carry blood away from the heart and to the organs while veins carry blood to the heart and away form the tissue and organs. Capillaries connect the arterioles (tiny arteries) to the venules (tiny veins) and they are responsible for exchanging nutrients for waste products with cells. Most of our organs contain a single capillary system but some contain a portal system, which is a network of two different capillary systems. The pulmonary blood flow begins when the right ventricle contracts and brings blood into the pulmonary artery. It then carries blood into the small arteries and into the capillaries of the lungs. Oxygen is brought into the blood and carbon dioxide is taken out and the blood within our lungs and then the blood goes into the pulmonary veins, which carries the oxygenated blood into the left atrium (this is where pulmonary circulation ends). From the left atrium, blood moves into the left ventricle. When the left ventricle contracts, it forces blood into our systemic circulatory system, moving blood into the aorta and the rest of the organs found in the upper and lower portions of our body. The blood then returns back into the right atrium of the heart via the inferior and superior vena cava.
Composition of Blood: Blood is a connective tissue, which implies that is consists of a collection of cells surrounded by an extracellular matrix. The extracellular matrix (or simply the matrix) is the blood plasma. Blood plasma consists mostly of water but also contains proteins (albumin, immunoglobulins, fibrinogen), nutrients (sugars, fatty acids, amino acids), waste products (urea, lactic acid, carbon dioxide), electrolytes (sodium, calcium, chloride, bicarbonate) and hormones. The function of blood plasma is to create a fluid-like substance through which all these different types of nutrients and waste products can move from one location to a different location in the body. It is used to regulate the concentration of the matrix of all the different cells in our body. The blood consists of about 55% blood plasma by volume. The remaining 45% consists of cells. There are three types of cells - erythrocytes, leukocytes and thrombocytes. Erythrocytes, also called red blood cells, carry oxygen from one cell to another. Leukocytes, also known as white blood cells, come in many different types. These fight off bacterial and viral infections. Thrombocytes, also called platelets, are involved in the blood clotting process.
Types of Blood Vessels: Blood vessels are the conduits of our cardiovascular system that move blood from one location to another. There are three major types of blood vessels in our body - arteries, veins and capillaries. Arteries contain a three-layer system (tunica intima, tunica media and tunica extrena) that consists of a thick smooth muscle layer. This makes arteries flexible yet gives them a high resistance to flow. This means that when blood fills arteries and expands their volume, these same arteries can easily recoil and return back to their original shape. This is the method by which blood moves within arteries. The smooth muscle layer of the smaller arteries, called arterioles is innervated and controlled by the autonomic nervous system. Veins also have the same three layers but the thickness of the smooth muscle layer is much smaller. This makes veins very inelastic and easily expandable. Therefore, they do not recoil and can easily expand to contain more volume of blood. Veins also have a system of one-way valves in place that allows the blood to flow in one direction against the force of gravity. The skeletal muscle found around veins also helps move the blood along the veins. Capillaries are very tiny blood vessels (a single cell layer thick) that are responsible for exchanging nutrients and waste products with the cells in our body.