Lecture 1: Chapter 1

An Introduction to Anatomy and

Physiology

BY

MK SASTRY

Learning Objectives

• Describe the basic functions of organisms.

• Define anatomy and physiology and the various specialties of each.

• Identify the major levels of organization in organisms .

• Identify the 11 organ systems of the body and their major components.

• Explain the concept of homeostasis, including both positive and negative feedback.

• Using the proper anatomical terms, identify the major body cavities.

• Organization

• Responsiveness

• Growth and differentiation

• Reproduction

• Movement

• Metabolism and excretion

The basic functions of organisms

• Anatomy can be divided into gross and microscopic:

• Forms of Gross Anatomy

• Surface anatomy – study of superficial marking

• Regional anatomy – study of specific area

• Systemic anatomy – study of system

• Developmental anatomy – study changes from conception to physical maturity.

• Microscopic anatomy includes two major subdivisions

• Cytology – study of cell

• Histology – study of tissue

The Specialties of Anatomy

• All vertebrates share a basic pattern of organization, most noticeable during embryology.

Comparative Anatomy

• Physiology is the study of the normal function of cell, tissue, organs, systems and organisms

• Physiology can be divided into the following specialties:

• Cell physiology – study of cell

• Special physiology - study of specific organ

• Systemic physiology – study of system

• Pathological physiology – study of the effect of disease on cell, tissue, organ and system.

The Specialties of Physiology

Levels of Organization

Levels of Organization

• Integumentary system

• Nervous system

• Skeletal system

• Endocrine system

• Muscular system

• Cardiovascular system

• Lymphatic system

• Urinary system

• Respiratory system

• Digestive system

• Reproductive system

An Introduction to the Organ Systems

• Autoregulation or intrinsic regulation – results when cell, organ or system adjusts its activity automatically.

• Extrinsic regulation - results from activity of nervous system or endocrine system

Homeostasis

Two general points within homeostasis

•Homeostasis is a stable internal environment

•Every organism must maintain homeostasis for survival

•Homeostatic regulation is responsible for keeping

internal environment within certain limits.

• A homeostatic regulatory mechanism consist of :

• A receptor – senses an environmental change or stimuli.

• A control center –processes information supplied by receptor and generates a response (command)

• An effector – an organ or cell that responds to the command of control center.

• A variation outside the desired range triggers an automatic response to correct the situation

• Negative feedback

Homeostatic regulation involves

Negative Feedback: The Control of Body Temperature

Positive Feedback: Blood Clotting

•In positive feedback an initial stimulus produces a response that

enhances the change in the original condition. For instance:

• Damage to blood vessel wall will cause release of chemicals.

•Chemicals will trigger blood clotting

•Clotting process increases release of chemicals

•More chemicals means accelerated clotting

•Accelerated clotting means more chemicals

• Body cavities are internal chambers holding vital organs

• Cavities protect vital organs

• Cavities allow organs to change in shape and size

• Two body cavities

• Dorsal body cavity includes the cranial cavity and the spinal cavity

• Ventral body cavity includes the thoracic cavity and the abdominopelvic cavity

Body Cavities

Body Cavities

• The thoracic cavity contains the heart and lungs.

• The thoracic cavity is subdivided into:

• Left and right pleural cavities (each pleural cavity contains one lung) lined by the visceral and parietal pleura

• The mediastinum contains the pericardium (pericardial cavity), another serous membrane that surrounds the heart

Thoracic Cavities

Animation: Heart Dissection (see tutorial)

• The abdominopelvic cavity is lined by the peritoneum

• The abdominal cavity extends from the diaphragm to the superior margins of the pelvis

• liver, stomach, spleen and most of the large intestine

Abdominopelvic Cavity

• The pelvic cavity is bordered by the pelvis, with a floor of muscle

• reproductive organs, urinary bladder and the final portion of the large intestine

Abdominopelvic Cavity

Animation: Digestive System Dissection (see tutorial)

• X-rays

• Computerized tomography (CT) scans

• Magnetic resonance imaging (MRI) scans

• Ultrasound images

• Spiral CT scans

• Digital subtraction angiography images (DSA)

• Positron emission tomography (PET) scans

Clinical technology allows many different views of the body

X-rays

Common scanning techniques

Special Scanning Methods

• The characteristics of life.

• The sciences of anatomy and physiology and their various subdivisions.

• The levels of organization in the human body.

• The definition and importance of homeostasis.

• The terminology associated with superficial and sectional anatomy and the body cavities.

You should now be familiar with: