Chapter 1 anatomy

What is anatomy?

The study of structure and shape of the body and its parts and their relationships to one another.

What are the subdivisions of anatomy?

Gross (macroscopic), Microscopic, and Developmental (embryology).

What is physiology?

The study of how the body works or functions, based on organ systems.

How are anatomy and physiology related?

Anatomy and physiology are always related; structure determines function.

What are the levels of structural organization in the body?

Chemical, Cellular, Tissue, Organ, Organ system, Organism.

What are the components of the integumentary system?

Skin, nails, hair.

What is one function of the muscular system?

Contracting to allow movement, manipulation of environment, locomotion, and facial expression.

What does the nervous system control?

It is the control center of the body that regulates, senses, and responds to internal and external changes.

What are the main functions of the cardiovascular system?

Delivers oxygen and nutrients to tissues, equalizes temperature in the body, and transports waste from cells.

What does the respiratory system do?

Supplies blood with oxygen and removes carbon dioxide.

What is homeostasis?

The maintenance of relatively stable internal conditions necessary to sustain life.

What are afferent pathways?

Pathways that carry sensory information towards the CNS.

What is the function of effectors in homeostatic control?

Effectors provide a means for response to the stimulus.

Define negative feedback.

A homeostatic control mechanism that shuts off the original stimulus or reduces its intensity.

What is an example of positive feedback in the body?

Blood clotting and childbirth.

What are the major internal body cavities?

Dorsal and ventral body cavities.

What does the anatomical position assume about the body?

The body is erect, feet parallel, arms hanging at the sides, and palms facing forward.

Anatomy

The study of structure & shape of the body and its parts and their relationships to one another.

Physiology

The study of how the body works or functions, based on organ systems.

Gross or macroscopic anatomy

Anatomical structures visible to the naked eye.

Microscopic anatomy

Anatomical structures too small to see with the naked eye.

Developmental anatomy

The study of structural changes in the body from conception to old age, including embryology.

Chemical level

The simplest level, involving atoms and molecules.

Cellular level

Cells and their organelles.

Tissue level

Groups of similar cells working together to perform a specific function.

Organ level

Contains two or more types of tissues that work together to perform specific functions.

Organ system level

Organs that work closely together to accomplish a common purpose.

Organism level

The highest level of structural organization, encompassing all organ systems working together.

Integumentary System

Forms the external body covering, protects underlying tissues, synthesizes vitamin D, and contains sensory receptors and glands.

Skeletal System

Protects and supports body organs, provides a framework for muscles, is the site of blood formation, and stores minerals.

Muscular System

Allows movement, manipulation of the environment, locomotion, facial expression, maintains posture, and produces heat.

Nervous System

The control center of the body; regulates, senses, and responds to internal and external changes by activating motor neurons, muscles, and glands.

Endocrine System

Secretory glands that produce hormones regulating processes such as growth, reproduction, and metabolism.

Cardiovascular System

Delivers oxygen and nutrients to tissues, transports waste from cells, and equalizes body temperature.

Lymphatic & Immune System

Assists the cardiovascular system in returning leaked fluids to the bloodstream, cleanses the blood, and houses white blood cells for immunity.

Respiratory System

Supplies blood with oxygen and removes carbon dioxide.

Digestive System

Breaks down food, allows for nutrient absorption into the blood, and eliminates indigestible material.

Urinary System

Eliminates nitrogenous wastes, maintains acid-base balance, regulates water and electrolyte balance, and helps regulate normal blood pressure.

Reproductive System

Involves the production of offspring; testes produce sperm in males, ovaries produce eggs and the uterus provides development for the fetus in females.

Maintaining Boundaries (Life Function)

Separating cell contents from interstitial substances, and the skin protecting internal organs.

Movement (Life Function)

Propulsion (walking, swimming), manipulating the environment, and movement of blood, nutrients, urine, and bowels.

Response to Stimuli (Life Function)

The ability to sense environmental changes and react, involving feedback mechanisms and autonomic responses.

Digestion (Life Function)

The process of breaking down ingested food into smaller, simple molecules that can be absorbed by body cells.

Metabolism (Life Function)

All chemical reactions that occur in the body, including breaking down substances, using nutrients, and ATP production.

Excretion (Life Function)

The process of removing waste products from the body, such as indigestible food (feces), urea (urine), and sweat (skin).

Reproduction (Life Function)

Involves the production of offspring, at both the cellular and organismal levels.

Growth (Life Function)

An increase in size, usually by an increase in the number of cells.

Nutrients (Survival Need)

Chemical substances used for energy and cell building (macronutrients like carbohydrates, protein, fat; micronutrients like vitamins, minerals, co-factors).

Oxygen (Survival Need)

Required for chemical reactions that release energy from food; deprivation leads to death within minutes.

Water (Survival Need)

Comprises 60-80% of body weight and is the most abundant chemical substance in the body.

Temperature (Survival Need)

Body temperature for optimal metabolic reactions (e.g., 98.6\degree F); deviations lead to slow or too rapid reactions and can result in death.

Atmosphere (Survival Need)

The weight of air that impacts oxygen-carbon dioxide exchange in the lungs.

Anatomical position

A standard body position where the body is erect, feet parallel, arms hanging at the sides, and palms facing forward.

Anterior (or ventral)

Describes the front or direction toward the front of the body.

Posterior (or dorsal)

Describes the back or direction toward the back of the body.

Superior (or cranial)

Describes a position above or higher than another part of the body.

Inferior (or caudal)

Describes a position below or lower than another part of the body proper; near or toward the tail.

Lateral

Describes the side or direction toward the side of the body.

Medial

Describes the middle or direction toward the middle of the body.

Proximal

Describes a position in a limb that is nearer to the point of attachment or the trunk of the body.

Distal

Describes a position in a limb that is farther from the point of attachment or the trunk of the body.

Superficial

Describes a position closer to the body surface.

Deep (internal)

Describes a position away from the body surface; toward the internal part of the body.

Section

A cut along a body plane.

Sagittal section

A cut along the longitudinal plane of the body dividing it or an organ into right and left parts.

Midsagittal (median) section

A sagittal cut resulting in equal right and left halves.

Frontal (coronal) section

A cut along the lengthwise plane that divides the body into anterior and posterior parts.

Transverse (cross) section

A cut along a horizontal plane dividing the body or organ into superior and inferior parts.

Dorsal Body Cavities

Internal body cavities that house and protect organs, specifically the cranial and spinal cavities.

Cranial cavity

Space inside the skull that houses the brain.

Spinal cavity

Extends from the cranial cavity to the end of the spinal cord and surrounds the spinal cord.

Ventral Body Cavities

Contains all structures within the chest and abdomen, primarily the thoracic and abdominopelvic cavities.

Thoracic cavity

Space inside the chest, separated from the abdominopelvic cavity by the diaphragm, containing the lungs and heart.

Abdominopelvic cavity

A large cavity inferior to the diaphragm, subdivided into the superior abdominal cavity and the lower pelvic cavity.

Homeostasis

The maintenance of relatively stable internal conditions; a dynamic state of equilibrium necessary to sustain life.

Homeostatic imbalance

A disturbance in homeostasis that results in illness or disease.

Receptor (Homeostatic Control)

Responds to changes in the environment (stimuli) and sends information to the control center.

Control center (Homeostatic Control)

Determines the set point, analyzes information from the receptor, and determines the appropriate feedback response.

Effector (Homeostatic Control)

Provides a means for response to the stimulus, receiving information from the control center.

Afferent pathway

Transmit information about stimuli from the body's periphery to the Central Nervous System (CNS) for sensory perception and initiating reflexes.

Efferent pathway

Transmit signals from the CNS to effector organs (muscles and glands) to produce a response (e.g., muscle contraction, gland secretion).

Negative feedback

Includes most homeostatic control mechanisms; it shuts off the original stimulus or reduces its intensity.

Positive feedback

Rare in the human body; it increases the original stimulus to push the variable farther, occurring at a faster rate (e.g., blood clotting and childbirth).

Acromial

point of shoulder

Cephalic

Head Region

Cervical

neck region

Frontal

Forehead

Nasal

Nose area

Oral

Mouth

orbital/ocular

eyes

Axillary

Armpit

Costal

Ribs

Deltoid

Curve of shoulder formed by deltoid muscles

Calcaneal

heel of foot

Pectoral

chest

Sternal

Breastbone area

Abdominal

Anterior trunk, inferior to ribs

Inguinal

Groin area where thigh meets body

Pelvic

area anterior to pelvis

Pubic

Genital area