The Human Organism - Anatomy & Physiology Flashcards

Vocabulary terms and definitions from Chapter 1 of Seeley’s Essentials of Anatomy & Physiology, covering levels of organization, organ systems, homeostasis, and anatomical terminology.

Anatomy

The investigation of body structure; the term literally means to dissect.

Physiology

The investigation of processes and functions of the body.

Systemic Physiology

The study of body organ-systems.

Cellular Physiology

The study of body cells.

Regional Anatomy

The study of body regions, such as those taught in medical schools.

Surface Anatomy

The study of external features, such as bone projections.

Anatomical imaging

The use of technologies such as x-rays, ultrasound, and MRI to view body structures.

Chemical level

The smallest level of structural organization, consisting of atoms, chemical bonds, and molecules.

Cellular level

The level of organization consisting of cells, which are the basic units of life containing compartments and organelles like the nucleus and mitochondria.

Tissues

A group of cells with similar structure and function plus the extracellular substances they release.

Organs

Two or more tissue types acting together to perform one or more functions; examples include the stomach, heart, and kidney.

Organ-System

A group of organs contributing to a common function, such as the digestive or reproductive systems.

Organism

All organ systems working together, including associated microorganisms like intestinal bacteria.

Integumentary System

Provides protection, regulates temperature, prevents water loss, and helps produce vitamin D; consists of skin, hair, nails, and glands.

Skeletal System

Provides protection and support, allows movements, produces blood cells, and stores minerals; consists of bones, cartilages, ligaments, and joints.

Muscular System

Produces body movements, maintains posture, and produces body heat; consists of muscles attached to the skeleton by tendons.

Nervous System

A major regulatory system that detects sensations and controls movements, physiological processes, and intellectual functions.

Endocrine System

A major regulatory system that influences metabolism, growth, and reproduction via hormones secreted by glands like the pituitary.

Cardiovascular System

Transports nutrients, waste products, gases, and hormones; plays a role in immune response and temperature regulation.

Lymphatic System

Removes foreign substances from blood and lymph, combats disease, maintains fluid balance, and absorbs dietary fats.

Respiratory System

Exchanges oxygen and carbon dioxide between the blood and air and regulates blood pH.

Digestive System

Performs mechanical and chemical digestion, absorption of nutrients, and elimination of wastes.

Urinary System

Removes waste products from the blood and regulates blood pH, ion balance, and water balance.

Metabolism

The sum of all chemical and physical changes sustaining an organism, including the ability to acquire and use energy.

Responsiveness

The ability of an organism to sense and respond to changes in both its internal and external environments.

Differentiation

Changes in cell structure and function from generalized to specialized during development.

Homeostasis

The maintenance of a constant internal environment despite fluctuations in the external or internal environment.

Variables

Measures of body properties that may change in value, such as body temperature, heart rate, or blood pressure.

Set point

The normal or average value of a variable.

Negative feedback

The main homeostatic mechanism that involves detection of a deviation from the set point and a corrective response to reversal that deviation.

Receptor

The component of a feedback system that detects changes in a variable.

Control center

The component of a feedback system that receives the receptor signal, establishes the set point, and sends signals to the effector.

Effector

The component of a feedback system that directly causes a change in the variable.

Positive feedback

A mechanism where the initial stimulus further stimulates the response, causing progressive deviation away from the set point; usually associated with injury or disease.

Anatomical position

A standard position where a person stands erect with face and palms forward.

Superior

A directional term meaning above; also called cephalic.

Inferior

A directional term meaning below; also called caudal.

Anterior

A directional term meaning front; also referred to as ventral.

Posterior

A directional term meaning back; also referred to as dorsal.

Medial

A directional term meaning close to the midline.

Lateral

A directional term meaning away from the midline.

Proximal

A directional term meaning close to the point of attachment.

Distal

A directional term meaning far from the point of attachment.

Superficial

A directional term describing a structure close to the surface.

Deep

A directional term describing a structure toward the interior of the body.

Sagittal plane

A plane that separates the body into right and left parts.

Median plane

A sagittal plane along the midline that divides the body into equal left and right halves.

Transverse plane

A horizontal plane that separates the body into superior and inferior parts.

Frontal plane

A vertical plane that separates the body into anterior and posterior parts; also called a coronal plane.

Thoracic cavity

The space within the chest wall and diaphragm containing the heart, lungs, thymus, esophagus, and trachea.

Mediastinum

The space between the lungs containing the heart, thymus gland, esophagus, and trachea.

Abdominal cavity

The space between the diaphragm and pelvis containing the stomach, intestines, liver, spleen, pancreas, and kidneys.

Pelvic cavity

The space within the pelvis containing the urinary bladder, reproductive organs, and part of the large intestine.

Visceral serous membrane

The inner layer of the serous membrane that directly covers the organs.

Parietal serous membrane

The outer layer of the serous membrane lining the cavity wall.

Pericardium

The serous membrane and cavity surrounding the heart.

Pleura

The serous membrane and cavity surrounding the lungs.

Peritoneum

The serous membrane and cavity surrounding the abdominopelvic cavity and its organs.

Mesenteries

Double layers of visceral peritoneum that cover and anchor organs.