Chapter 1: The Human Body: An Orientation Flashcards

Vocabulary flashcards covering overview of anatomy and physiology, levels of organization, requirements for life, homeostasis, directional terminology, body planes, cavities, and serous membranes.

Anatomy

The study of the body's structure.

Physiology

The study of how the body works.

Gross (macroscopic) anatomy

The study of large, visible structures.

Microscopic anatomy

The study of tiny structures.

Principle of complementarity of structure and function

The principle stating that the structure of a body part (anatomy) is directly related to its function (physiology).

Six levels of structural organization

In order: Chemical level, Cell, Tissue, Organ, Organ system, Organism.

Cell

The basic structural and functional unit of all life.

Tissue

A group of similar cells that together carry out a common function.

Organ

A structure composed of at least two tissues that performs a specific function.

Organ system

A group of organs that work together to perform one or more functions.

Organism

Any living thing that functions as an individual.

Eight necessary life functions

Maintaining boundaries, Movement, Responsiveness, Digestion, Metabolism, Excretion, Reproduction, and Growth.

Cellular boundary structure

The cell membrane, which is responsible for maintaining boundaries at the cellular level.

Organisational boundary structure

The integumentary system, which is responsible for maintaining boundaries at the organismal level.

Metabolism

The sum of all chemical reactions in the body.

Anabolism

The process of building up molecules.

Catabolism

The process of breaking down molecules.

Five survival needs

Nutrients, Oxygen, Water, Normal blood temperature, and Appropriate atmospheric pressure.

Homeostasis

The process by which the body maintains a stable internal environment despite external changes, ensuring vital functions stay within optimal constant ranges.

Variable (homeostasis)

The physiological factor being regulated.

Stimulus

A change in the internal or external environment that causes a variable to move outside its normal range.

Set point

The ideal normal range for a regulated variable.

Receptor

A specialized sensory cell or organ that detects a stimulus, sensing a change in the variable and sending input to the control center.

Control center

The component that receives input from the receptor, compares it to set point/variables, analyzes the input, and determines an appropriate response.

Effector

A muscle or gland that receives output from the control center and executes action to correct an imbalance, returning the variable to normal level.

Negative feedback mechanism

A control mechanism where a change in a given direction causes a change in the opposite direction, moving the variable toward the set point.

Positive feedback mechanism

A control mechanism where a change in a given direction causes a change in the same direction, moving the variable further away from the set point.

Anatomical position

Body erect, feet slightly apart, palms facing forward with thumbs pointing away from the body.

Superior

Toward the head or upper body.

Inferior

Away from the head or lower body.

Anterior (ventral)

Toward or at the front of the body.

Posterior (dorsal)

Toward or at the back of the body.

Medial

Toward or at the midline of the body.

Lateral

Away from the midline of the body.

Proximal

Closer to the origin of the body part or point of attachment of a limb to the body.

Distal

Further from the origin of a body part or point of attachment of a limb to the body.

Superficial

Toward or at the body surface; more external.

Deep

Away from the body surface; more internal.

Sagittal plane

A vertical plane that divides the body into left or right sides.

Frontal (coronal) plane

A vertical plane that divides the body into anterior and posterior parts.

Transverse plane

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

Midsagittal (median) plane

A plane that passes down the exact midline of the body.

Cross section

A section made along the transverse plane.

Dorsal body cavity

Body cavity subdivided into the cranial cavity and vertebral cavity.

Ventral body cavity

Body cavity subdivided into the thoracic cavity and abdominopelvic cavity.

Diaphragm

The muscle structure that separates the thoracic cavity and abdominopelvic cavity.

Thoracic cavity subdivisions

Pleural cavities, pericardial cavity, and mediastinum.

Abdominopelvic cavity subdivisions

Abdominal cavity and pelvic cavity.

Cranial cavity

Body cavity containing the brain and pituitary gland.

Vertebral cavity

Body cavity containing the spinal cord.

Pleural cavity

Subdivision of the thoracic cavity containing the lungs.

Pericardial cavity

Subdivision of the thoracic cavity containing the heart.

Abdominal cavity

Subdivision of the abdominopelvic cavity containing the stomach, liver, and kidneys.

Pelvic cavity

Subdivision of the abdominopelvic cavity containing urinary, digestive, and reproductive organs.

Serous membrane

Double-layered sheets that line closed body cavities and wrap around organs.

Parietal serosa

The layer of a serous membrane that lines the walls of cavities.

Visceral serosa

The layer of a serous membrane that directly covers organs.

Serous cavity

The potential space between the visceral serosa and parietal serosa layers.

Serous fluid

Fluid contained within the serous cavity that acts as a lubricant.