Introduction to the Human Body Tenth Edition Gerard J. Tortora Bryan H. Derrickson Chapter 1 Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Anatomy and physiology defined Levels of organization and body systems Life processes Homeostasis Anatomical terms Body cavities Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

ANATOMY AND PHYSIOLOGY DEFINED Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Anatomy and Physiology Defined Anatomy is the science of structure and the relationships among structures. Physiology is the science of body functions, that is, how the body parts work. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

LEVELS OF ORGANIZATION AND BODY SYSTEMS Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Chemical Level 1. Chemical level includes:  Atoms – the smallest units of matter that participate in chemical reactions.  Molecules – two or more atoms joined together. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Cellular Level 2. Cells are the basic structural and functional units of an organism.  Just as words are the smallest elements of language, cells are the smallest living units in the human body.  Types of cells in the human body are muscle cells, nerve cells, and blood cells. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Tissue Level 3. Tissues are groups of cells and the materials surrounding them that work together to perform a particular function.  Cells join together to form tissues.  There are four basic types of tissue in the body:  Epithelial tissue  Connective tissue  Muscular tissue  Nervous tissue Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organ Level 4. Organs are composed of two or more different types of tissues, and have specific functions.  Tissues join together to form organs similar to the way sentences are put together to form paragraphs.  Examples of organs are:  Stomach, heart, liver, lungs, and brain. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

System Level 5. System consists of related organs that have a common function.  Organs join together to form systems similar to the way paragraphs are put together to form chapters.  Example is the digestive system, which breaks down and absorbs molecules in food. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organismal Level 6. Organismal level is the largest level of organization.  All of the systems of the body combine to make up an organism.  Systems join together to form an organism similar to the way chapters are put together to form a book. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

LIFE PROCESSES Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Life Processes All living organisms have certain characteristics that set them apart from nonliving things. There are six important life processes of humans:  Metabolism  Responsiveness  Movement  Growth  Differentiation  Reproduction Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Life Processes 1. Metabolism is the sum of all the chemical processes that occur in the body. 2. Responsiveness is the body’s ability to detect and respond to changes in its environment. 3. Movement includes motion of the whole body, individual organs, single cells, and even tiny organelles inside cells. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Life Processes 4. Growth is an increase in body size. It may be due to an increase in the size of existing cells, the number of cells, or the amount of material surrounding cells. 5. Differentiation is the process whereby unspecialized cells become specialized cells. 6. Reproduction is the formation of new cells for growth, repair, or replacement or the production of a new individual. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

HOMEOSTASIS Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Homeostasis: Maintaining Limits Homeostasis is the maintenance of relatively stable conditions, this ensures that the body’s internal environment remains constant despite changes inside and outside the body. A large part of the internal environment consists of the fluid surrounding body cells, called interstitial fluid. Each body system contributes to homeostasis in some way. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Homeostasis: Feedback Systems The body is mainly under the control of two systems: the nervous system and the endocrine system. The nervous system detects changes from the balanced state and sends messages in the form of nerve impulses to organs that can counteract the change. The endocrine system corrects changes by secreting molecules called hormones into the blood. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Homeostasis: Feedback Systems Homeostasis is maintained by means of many feedback systems. A feedback system or feedback loop is a cycle of events in which a condition in the body is continually monitored, evaluated, changed, remonitored or reevaluated. 3 basic components make up a feedback system: a receptor, a control center, an effector. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Animation Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. You must be connected to the internet to run this animation. Communication, Regulation and Homeostasis

Animation Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. Homeostatic Relationships You must be connected to the internet to run this animation.

Homeostasis: Feedback Systems Negative Feedback Systems: A negative feedback system reverses a change in a controlled condition. Example: regulation of blood pressure. Positive Feedback Systems: Unlike a negative feedback system, a positive feedback system tends to strengthen or reinforce a change in one of the body’s controlled conditions. Example: normal childbirth. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Organization of the Human Body Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Animation Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. Negative Feedback Control of Blood Pressure You must be connected to the internet to run this animation.

Animation Copyright © 2015 John Wiley & Sons, Inc. All rights reserved. Positive Feedback Control of Labor You must be connected to the internet to run this animation.

ANATOMICAL TERMS Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Anatomical Terms The language of anatomy and physiology is very precise. Anatomical position is when the subject stands erect facing the observer, with the head level and the eyes facing forward. The lower limbs are parallel and the feet are flat on the floor and directed forward, and the upper limbs are at the sides with the palms turned forward In the anatomical position, the body is upright. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Anatomical Position Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Anatomical Terms Two terms describe a reclining body. If the body is lying face down, it is prone. If the body is lying face up, it is supine. Examples of exact terms that will be used are in:  Body regions  Directional terms  Planes and sections Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Regions The human body is divided into several major regions that can be identified externally:  Head  Neck  Trunk  Upper limbs  Lower limbs Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Directional Terms To locate various body structures, anatomists use specific directional terms, words that describe the position of one body part relative to another. Most of the directional terms used to describe the human body can be grouped into pairs that have opposite meanings. For example, superior means toward the upper part of the body, and inferior means toward the lower part of the body. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Directional Terms Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Directional Terms Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Planes and Sections The body has four major planes, that is, imaginary flat surfaces that pass through body parts: Sagittal plane is a vertical plane that divides the body or an organ into right and left sides. When such a plane passes through the midline of the body or organ and divides it into equal right and left sides, it is called midsagittal. If it divides the body or an organ into unequal right and left sides, it is a parasagittal plane. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Planes and Sections Frontal plane or coronal plane divides the body or an organ into anterior (front) and posterior (back) portions. Transverse plane divides the body or an organ into superior and inferior portions. This plane may also be called a cross-sectional plane. Oblique plane passes through the body or an organ at an angle between the other planes. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Planes and Sections Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Planes and Sections Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

BODY CAVITIES Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Body cavities are spaces within the body that contain, protect, separate, and support internal organs. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Cranial cavity is formed by the cranial (skull) bones and contains the brain. Vertebral canal is formed by the bones of the vertebral column (backbone) and contains the spinal cord. Thoracic cavity is the chest cavity. Within the thoracic cavity are three smaller cavities: the pericardial cavity, two pleural cavities, and the mediastinum. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Abdominopelvic cavity extends from the diaphragm to the groin. As the name suggests, it is divided into two portions:  The upper portion, the abdominal cavity contains the stomach, spleen, liver, gallbladder, small intestine, and most of the large intestine.  The lower portion, the pelvic cavity contains the urinary bladder, portions of the large intestine, and internal organs of the reproductive system. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

Body Cavities Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.

End of Chapter 1 Copyright 2015 John Wiley & Sons, Inc. All rights reserved. Reproduction or translation of this work beyond that permitted in section 117 of the 1976 United States Copyright Act without express permission of the copyright owner is unlawful. Request for further information should be addressed to the Permission Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for distribution or resale. The Publishers assumes no responsibility for errors, omissions, or damages caused by the use of these programs or from the use of the information herein. Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.