Anatomy & Physiology For Dummies

Erin Odya, Maggie A. Norris

• Publisher: For Dummies
• Year: 2017
• ISBN:
  9781119345305
• Edition: 3
• Topic: Biological Sciences
• Subtopic: Human Anatomy & Physiology
• Index: Biological Sciences

Learn about the human body from the inside out

Some people think that knowing about what goes on inside the human body can sap life of its mystery—which is too bad for them. Anybody who's ever taken a peak under the hood knows that the human body, and all its various structures and functions, is a realm of awe-inspiring complexity and countless wonders. The dizzying dance of molecule, cell, tissue, organ, muscle, sinew, and bone that we call life can be a thing of breathtaking beauty and humbling perfection.

Anatomy & Physiology For Dummies combines anatomical terminology and function so you'll learn not only names and terms but also gain an understanding of how the human body works. Whether you're a student, an aspiring medical, healthcare or fitness professional, or just someone who's curious about the human body and how it works, this book offers you a fun, easy way to get a handle on the basics of anatomy and physiology.

• Understand the meaning of terms in anatomy and physiology
• Get to know the body's anatomical structures—from head to toe
• Explore the body's systems and how they interact to keep us alive
• Gain insight into how the structures and systems function in sickness and health

Written in plain English and packed with beautiful illustrations, Anatomy & Physiology For Dummies is your guide to a fantastic voyage of the human body.

Part 1

Locating Physiology on the Web of Knowledge

IN THIS PART …

Get acquainted with the basics of anatomy and physiology.

Find out about metabolism — all the chemical reactions that keep you alive.

Learn how we keep everything in check — maintaining balance in our bodies.

Brush up on biochemistry.

Find the fundamentals of cell biology.

See how cells organize into tissues.

Chapter 1

Anatomy and Physiology: The Big Picture

IN THIS CHAPTER

Placing anatomy and physiology in a scientific framework

Jawing about jargon

Looking at anatomy: planes, regions, and cavities

Delineating life’s levels of organization

Human anatomy is the study of the human body’s structures — all the parts that make up the physical body itself. Physiology is the study of how the human body works; how all the anatomical parts function together to keep an individual alive. Anatomy and physiology are bound together. As such, this book abandons the old technique of learning all the anatomy and then the physiology as though the two were independent. Here, we examine each body system, identify the structures within that system, and then discuss their functions.

Scientifically Speaking

Human anatomy and physiology are closely related to biology, which is the study of living things and their relationship with the rest of the universe, including all other living things. If you’ve studied biology, you understand the basics of how organisms operate. Anatomy and physiology narrow the science of biology by looking at the specifics of one species: Homo sapiens.

Anatomy is form; physiology is function. You can’t talk about one without talking about the other.

THE ANATOMY AND PHYSIOLOGY OF EVERYTHING ELSE

Scientifically speaking, human biology isn’t more or less complex, specialized, or cosmically significant than the biology of any other species, and all are interdependent. Every species of animal, plant, and fungus on the planet has both anatomy and physiology. So does each species of protist (one-celled creatures, like amoebae) and bacteria. At the cellular level (see Chapter 3), all these groups are astoundingly similar. At the levels of tissues, organs, and organ systems, plants are very different from animals, and both plants and animals are equally dissimilar to fungi.

Each of these major groups, called a kingdom, has its own characteristic anatomy and physiology. It’s evident at a glance to everyone at the beach that a starfish and a human are both animals, while the seaweed in the tide pool and the cedar tree on the shoreline are both plants. Obvious details of anatomy (the presence or absence of bright green tissue) and physiology (the presence or absence of movement) tell that story. The different forms within each kingdom have obvious differences as well: The cedar must stand on the shore, but the seaweed would die there. The starfish can move from one place to another within a limited range, while humans can (theoretically) go anywhere on the planet and survive there for at least a while. Scientists use these differences to classify organisms into smaller and smaller groups within the kingdom, until each organism is classified into its own special group.

Not that human anatomy and physiology aren’t special. Humans’ bipedal posture and style of locomotion are very special . There’s nothing like a human hand anywhere except at the end of a human arm. Perhaps most special of all is the anatomy and physiology that allows (or maybe compels) humans to engage in science: our highly developed brain and nervous system. It’s entirely within the norms of evolutionary theory that people would be most interested in their own species, so more humans find human anatomy and physiology more interesting than the anatomy and physiology of the tree. From here on, we’re restricting our discussion to the anatomy and physiology of our own species.

How anatomy and physiology fit into science

Biologists base their work on the assumption that every structure and process, no matter how tiny in scope, must somehow contribute to the survival of the individual. So each process — and the chemistry and physics that drive it — must help keep the individual alive and meeting the relentless challenges of a continually changing environment. Although anatomy and physiology combined are classified as a subsection of biology, it’s truly an interdisciplinary science.

Human pathophysiology is the study of “human anatomy and physiology gone wrong.” (The prefix path- is Greek for “suffering.”) It’s the interface of human biology and medical science. Clinical medicine is the application of medical science to alleviate an anatomical or physiological problem in an individual human.

Pathophysiology and clinical medicine aren’t the subject of this book, but we discuss applications of them when they’re particularly relevant to the physiology. You’re probably using this book to supplement instructional material in career training for a clinical environment, so the information throughout the book is slightly slanted in that direction. We chose the conditions that we briefly examine to demonstrate some characteristic of the system, especially its interaction with other systems, but we don’t discuss diagnosis or treatment.

TAXONOMY OF HOMO SAPIENS

Taxonomy is the science that seeks to classify and organize living things, expressed as a series of mutually exclusive categories. The highest (most inclusive) category is domain, of which there are three: Archea, Eubacteria, Eukaryota. Each of these domains is split into kingdoms, which are further divided until each individual organism is its own unique species. Outside of bacteria, all living things fall under the Eukaryota domain; the kingdoms are: Protista, Fungi, Plantae, and Animalia. Within each kingdom, the system classifies each organism into the hierarchical subgroups (and sometimes sub-subgroups) of phylum, class, order, family, genus, and species. Here’s the breakdown of humankind:

Kingdom Animalia: All animals.

Phylum Chordata: Animals that have a number of structures in common, particularly the notochord, a rodlike structure that forms the body’s supporting axis.

Subphylum Vertebrata: Animals with backbones.

Superclass Tetrapoda: Four-footed vertebrates.

Class Mammalia: Tetrapods with hair. Other classes of the vertebrata are Pisces (fish), Amphibia (frogs), Aves (birds), and Reptilia (scaly things).

Order Primates: Mammals with more highly developed brains, flexible hips and shoulders, and prehensile hands and feet (able to grasp).

Superfamily Hominoidea: Apes (chimpanzees, gorillas, orangutans, humans).

Family Hominidae: Great apes, including humans.

Genus Homo: The human species is the only surviving species of our genus, though this genus included several species in the evolutionary past.

Species Sapiens: All species are given a two-part Latin name, in which the genus name comes first and a species epithet comes second. The biologists who name species sometimes try to use a descriptor in the epithet. For humans, they could have chosen “bipedal” or “talking” or “hairless,” but they chose “thinker.”

Variety Sapiens: Some species get a “varietal” name, usually indicating a difference that’s ...