Chapter 1 The Human Organism – Vocabulary Flashcards

A vocabulary set of key anatomy & physiology terms and concise definitions based on Chapter 1 notes.

Anatomy

The investigation of internal and external body structure, including where things are, what structures are made of, and how parts relate to one another.

Physiology

The study of the processes and functions of anatomical structures, including how cells, organs, and systems work and how diseases affect them.

Gross (Macroscopic) Anatomy

The study of large structures visible to the naked eye.

Microscopic Anatomy

The study of structures requiring magnification (histology).

Systemic Anatomy

An approach to anatomy that studies the body by organ systems.

Regional Anatomy

An approach to anatomy that studies specific body regions.

Surface Anatomy

The study of external features and landmarks on the surface of the body.

Anatomical Imaging

Techniques (e.g., X-ray, ultrasound, MRI) used to visualize internal structures.

Structural Organization

The arrangement of the body from chemical level up to the organism level.

Chemical level

The smallest level of organization; atoms and molecules and their bonds.

Cellular level

Cells and their organelles; basic units of life.

Tissue

A group of cells with a common structure and function, plus the extracellular substances they release.

Epithelial tissue

Tissue that covers surfaces and lines cavities and glands.

Connective tissue

Tissues that support, protect, and bind other tissues together (e.g., bone, blood, fat).

Muscular tissue

Tissue responsible for movement through muscle contraction.

Nervous tissue

Tissue that transmits electrical impulses; includes neurons and supporting cells.

Organ

Two or more tissue types functioning together to perform a specific function.

Organ system

A group of organs contributing to a vital life function (e.g., digestive system).

Organism

All organ systems functioning together; the living individual.

Homeostasis

Maintenance of a relatively stable internal environment despite fluctuations in the external or internal environment.

Variable

A measurable body property that can change (e.g., temperature, heart rate, blood glucose).

Set point

The normal value around which a variable fluctuates; the target value for homeostatic regulation.

Receptor

Detects changes in a variable and sends information to the control center.

Control center

Receives information, sets the optimum value (set point), and sends commands to effectors.

Effector

Part of a feedback system that acts to change the variable and restore homeostasis.

Negative feedback

Regulatory mechanism that reverses a deviation from the set point toward normal; stabilizes the system.

Positive feedback

Regulatory mechanism that amplifies the initial stimulus; not typically used to maintain homeostasis (examples: blood clotting, labor).

Anatomical position

Standing erect, face forward, palms facing forward; left and right refer to the subject.

Superior

Towards the head; above.

Inferior

Towards the feet; below.

Anterior

Towards the front of the body (ventral in humans).

Posterior

Towards the back of the body (dorsal in humans).

Medial

Towards the midline of the body.

Lateral

Away from the midline of the body.

Proximal

Near the point of attachment to the trunk or to a point of reference.

Distal

Farther from the point of attachment or reference.

Superficial

Near the surface of the body.

Deep

Away from the surface; toward the interior.

Sagittal plane

Vertical plane that divides the body into right and left parts.

Frontal plane

Vertical plane that divides the body into anterior and posterior parts.

Body cavities

Open spaces that house internal organs; major cavities include thoracic, abdominal, and pelvic (and their subdivisions).

Thoracic cavity

Chest cavity that contains the heart, lungs, and other structures.

Mediastinum

Space between the lungs within the thoracic cavity; contains the heart, thymus, esophagus, and trachea.

Abdominal cavity

Cavity between the diaphragm and pelvis; contains stomach, intestines, liver, spleen, pancreas, and kidneys.

Pelvic cavity

Space within the pelvis; contains urinary bladder and reproductive organs.

Abdominopelvic cavity

Combined abdominal and pelvic cavities.

Serous membranes

Membranes lining trunk cavities and covering organs; consist of visceral and parietal layers with serous fluid in between.

Pericardium

Membrane around the heart; visceral and parietal layers with a pericardial cavity containing serous fluid.

Pleura

Membranes around the lungs; visceral and parietal layers with the pleural cavity containing serous fluid.

Peritoneum

Membrane around abdominal organs; visceral and parietal layers with the peritoneal cavity and mesenteries.

Mesenteries

Double layers of peritoneum that hold abdominal organs in place and contain vessels and nerves.