Understanding the Human Body: An Introduction to Anatomy and Physiology

This introductory lecture examines the anatomy of the fist-sized muscle that pumps blood through the body. We review the distinction between arteries and veins and discuss the location of the heart, its coverings, layers, and subdivisions.

In this lecture, we examine the functioning of the cardiac cycle. We also examine the functioning of the heart's conduction system, the functioning of the valves (which produce the heart's distinctive "lub-dub" sound), and possible complications, notably atherosclerosis.

This lecture examines the anatomy of the three vessel networks that circulate blood. We identify and describe the structure of the vessels that form these networks. Next, we examine the major circulatory routes for the blood: arterial and venous systemic circulation, pulmonary circulation, and hepatic portal circulation.

In this lecture, we examine the physiology of the large blood vessels—how they control blood flow, regulate blood pressure, and control bleeding when ruptured. We will also examine the composition of blood and the functions of each of its parts-plasma, white blood cells, and red blood cells.

This lecture examines the anatomy of the respiratory system. After studying the integration of the respiratory system with the circulatory system, we review the anatomy of the structures through which air enters the body and passes into the lungs.

We turn now to the physiology of the respiratory system. We examine the four areas where respiration occurs and the consequences of blocking this respiration. We review the physiology of the movement of gases into the lungs and of their exchange with waste gases. Finally, we turn to the central respiratory centers, and we examine some respiratory disorders and their treatments.

This is the first of seven lectures on the nervous system. We examine the anatomy of the brain-its principal components and its main anatomical divisions. Next we examine the divisions of the cerebrum and the functional areas of the cerebral cortex.

We turn now to the brain's physiology. After considering how the nervous and endocrine systems work together, we review the functions of the nervous system and of nervous tissue. The main divisions of the central and peripheral nervous systems are reviewed. Finally, we distinguish afferent from efferent nerves and describe the categories of cranial and spinal nerves.

This lecture examines the anatomy and functions of the spinal cord. We review the reflex arc, which allows the body to react rapidly to changes in the external environment. Finally, the lecture examines the categories and locations of the spinal nerves.

Begin by examining the autonomic nervous system, which controls the body's basic functions without conscious intervention by the higher brain centers. We distinguish between the parasympathetic nervous system, which promotes rest and recovery, and the sympathetic nervous system, which promotes "fight and flight." Finally, we will review the 12 pairs of cranial nerves and their functions.

Examine the anatomy of the eyeball, its coverings and functions, and the photoreceptors of the retina that allow us to perceive shades and colors of light. We also review the structure and functions of the lens, eyelids, lacrimal glands and ducts, and extrinsic eye muscles. Next, we consider how the eye perceives light and how the brain converts those perceptions into meaningful information.

We examine the anatomy of the organs of hearing: the external ear, the eardrum, the tympanic cavity, and the labyrinth. Next, the lecture reviews how these structures gather and transmit sound waves to the brain as nerve impulses. Finally, we examine the anatomy and functions of the vestibular apparatus, structures in the inner ear that govern balance.

This lecture examines memory and brain pathology and provides information about anesthesia and pain. First, we examine the nature, development, pathology, and mysteries of memory. We then examine kinds of damage to the brain and spinal cord and the results of such damage. We conclude by discussing anesthesia and referred pain.

This is the first lecture in a six-lecture examination of the digestive system. We examine the structures through which food passes before its conversion into nutrients for the body. We conclude by reviewing the four divisions of the stomach and its layers.

Having studied the anatomy of the mouth, esophagus, and stomach, we turn now to the processes of digestion, absorption of nutrients, and excretion of waste products. This lecture examines mechanical then chemical digestion. Next, we examine the three phases of gastric secretion, and the process of gastric emptying. Finally, we consider stomach and digestive disorders and their treatments.

This lecture examines the anatomy of the pancreas, liver, and gallbladder. First, we examine the gross and microscopic anatomy of the pancreas. We turn next to the liver. The location, size, and blood supply and routing of the liver are reviewed. Finally, the lecture examines the gallbladder and biliary tree-the duct system that drains bile from the liver into the gallbladder and the duodenum.

This lecture reviews the functions of the pancreas, the liver, and the biliary tree. The pancreas and liver secrete digestive juices and enzymes that aid in digestion and absorption. In this lecture, we review the components of the exocrine pancreas. After reviewing several pancreatic disorders, we turn to the liver and examine the various functions that it performs.

We turn now to the anatomy of the organs in which nutrients and water are extracted for use by the body and by which the resulting waste material is excreted from the body. The small intestine is the organ in which most of the absorption of nutrients and water occurs. We review its anatomical divisions, then turn next to the large intestine, or colon.

This last lecture on the digestive system examines the physiology of the small and large intestines and the rectum. First, we examine mechanical and chemical digestion in the small intestine. We turn next to the large intestine or colon, examining the reflexes that move feces into and through the colon for excretion. Finally, we examine the physiology of defecation.

This is the first of three lectures on the endocrine system, the glands that secrete hormones directly into spaces surrounding cells. We examine the functional differences between the endocrine and nervous systems, and the basic properties of hormones. Next, we look at the most important endocrine glands: the pituitary gland, the hypothalamus, and the adrenal glands.

This lecture examines the endocrine functions of the pancreas. As an endocrine organ, the pancreas produces insulin and glucagon. After reviewing the four cell types composing the endocrine pancreas, the lecture examines in detail several insulin-related disorders: two principal types of diabetes mellitus and hyperinsulinism.

This lecture examines the thyroid gland and the parathyroid glands. For each, we briefly review the gross and microscopic anatomy, its physiology, and the consequences of dysfunction. Thyroid dysfunction can lead to cretinism, myxedema, Graves' disease, and other pathologies. Parathyroid dysfunction can lead to disorders including bony demineralization.

This is the first of two lectures on the urinary system. We examine the anatomy of the kidneys, the ureters, and the bladder. We consider the kidneys' major functioning unit-the nephron. The lecture concludes by reviewing the conduits through which urine passes before excretion from the body.

The primary function of the urinary system is to maintain the body's homeostasis. This lecture focuses on the physiology of the nephron and how it filters many of the blood's components, reabsorbs some, and removes others. The lecture concludes by briefly reviewing the physiology of the ureters and bladder.