Anatomy and Physiology: Levels of Organization, Homeostasis, Body Cavities, and Membranes

Vocabulary flashcards covering the hierarchy of life, homeostasis control mechanisms, regional anatomical terms, body cavities, and serous membranes based on the lecture transcript.

Chemical level

The structural level of organization composed of atoms and molecules.

Cellular level

The structural level of organization where molecules are used to form cells.

Tissue level

The structural level of organization where cells come together to perform a particular function.

Organ level

The structural level of organization where different types of tissue join together to form an organ.

System level

The structural level of organization consisting of related organs with a common function.

Organismal level

The highest structural level of organization, representing a complete living organism.

Homeostasis

The maintenance of a stable and balanced internal environment through continuous regulatory processes.

Receptors

Structures that detect changes in a controlled condition and send information to the control center.

Control Center

The component of a feedback system (such as the brain) that evaluates received information, compares it to normal ranges, and issues commands when needed.

Effector

A body structure that receives commands from the control center and produces a response to restore the controlled condition.

Negative Feedback Loop

A regulatory mechanism that opposes or reduces a stimulus, reversing a change in a controlled condition to maintain stability.

Positive Feedback Loop

A regulatory mechanism that reinforces or increases a change in a controlled condition by strengthening the initial stimulus.

Cephalic

Anatomical regional term referring to the head.

Cervical

Anatomical regional term referring to the neck.

Trunk

Anatomical region consisting of the chest (thoracic region).

Pedal

Anatomical regional term referring to the feet, including the ankles.

Body Cavities

Internal spaces within the body that protect, separate, and support internal organs.

Cranial cavity

A body cavity formed by cranial bones that houses the brain.

Spinal cavity

A body cavity formed by the vertebral column that contains the spinal cord.

Meninges

Protective tissue layers that line the cranial cavity and spinal cavity.

Thoracic cavity

Chest cavity formed by the ribs, chest muscles, sternum, and thoracic portion of the vertebral column.

Pericardial Cavity

A fluid-filled space within the thoracic cavity surrounding the heart.

Pleural cavities

Two fluid-filled spaces located in the thoracic cavity, each surrounding a lung.

Mediastinum

The central region of the thoracic cavity between the lungs, extending from the sternum to the vertebral column and from the neck to the diaphragm, housing all thoracic organs except the lungs.

Diaphragm

A muscle that separates the thoracic cavity from the abdominopelvic cavity.

Abdominopelvic cavity

A large body cavity extending from the diaphragm down to the groin.

Abdominal cavity

The superior part of the abdominopelvic cavity containing the stomach, spleen, liver, gallbladder, small intestines, and most of the large intestine.

Pelvic cavity

The inferior part of the abdominopelvic cavity containing the urinary bladder, portions of the large intestine, and internal reproductive organs.

Viscera

The internal organs located inside the thoracic and abdominopelvic cavities.

Serous Membranes

Smooth, double-layered membranes associated with the thoracic and abdominal cavities that cover viscera and line cavity walls.

Visceral layer

The inner layer of a serous membrane that directly covers internal organs.

Parietal layer

The outer layer of a serous membrane that lines the inner body wall.

Serous fluid

A fluid located between the visceral and parietal layers of serous membranes that reduces friction, allowing organs to move smoothly.

Pleura

The serous membrane associated with the lungs and the pleural cavity.

Visceral pleura

The layer of the pleura that clings directly to the outer surface of the lungs.

Parietal pleura

The layer of the pleura that lines the chest wall.

Pericardium

The serous membrane associated with the pericardial cavity surrounding the heart.

Visceral pericardium

The inner layer of the pericardium that clings directly to the surface of the heart.

Parietal pericardium

The outer layer of the pericardium that lines the surrounding cavity wall.

Peritoneum

A smooth, slippery serous membrane that lines the abdominal cavity wall and covers many abdominal organs.

Visceral peritoneum

The layer of peritoneum that directly covers organs within the abdominal cavity.

Parietal peritoneum

The layer of peritoneum that lines the inner surface of the abdominal wall.

Mesentery

A double layer of peritoneum extending from the parietal wall to the visceral layer around organs, serving as a structural anchor, bridge for vessels and nerves, and connecting the gut to the back body wall.

Omentum

A specialized fold of peritoneum that connects one abdominal organ directly to another organ to protect and isolate infections.

Greater omentum

A large, fatty peritoneal fold extending from the stomach and hanging down over portions of the intestines.

Lesser omentum

A smaller fold of peritoneum connecting the stomach and duodenum to the liver.

Peritonitis

An inflammation of the peritoneum caused by surgical complications, peritoneal dialysis, feeding tubes, severe liver disease, pancreatitis, or physical trauma.