Body Cavities and Membranes

4 body cavities

1. Cranial cavity 2. vertebral canal 3. Thoracic cavity (pleural cavities, pericardial cavity) 4. abdominopelvic cavity( abdominal cavity and pelvic cavity)

pericardial cavity

separated from the visceral pericardium by a space

Viscera (vis·cer·a/ˈvisərə/)

singular- viscus - the internal organs in the main cavites of the body

potential spaces

some of the spaces between body membranes. notes: under normal conditions, the membranes are pressed firmly together and there is no actual space between them. Under unusual conditions, they may separeate and create a space filled with fluid or other matter. ex. pleural cavity( air) & uterus( pregnancy)

Thoracic cavity

Pleural cavity: lungs; pleurae (pleu·ra1/ˈplo͝orə/) Pericardial cavity: heart; pericardium

peritoneum membrane

Two-layer serous membrane that lines the abdominopelvic cavity contains: 1. parietal peritoneum 2. visceral peritoneum 3. peritoneal cavity 4. peritoneal fluid

Pleura

a serous membrane enfolded the lung -contains: 1. visceral pleura 2. partietal pleura 3. pleural cavity 4. pleural fluid

pericardial fluid

a small amount of fluid between the visceral pericardium and parietal pericardium between the layers prevents friction when the heartbeats

coelom

a space forms within the trunk during the embryonic development

Mediastinum(me·di·as·ti·num/ˌmēdēəˈstīnəm/)

a thick wall divided thoracic cavity notes: the region between the lungs, extending from the base of the neck to the diaphragm.

serous membrane

a thin layer of tissue that covers internal body cavities and secretes a fluid that keeps the membrane moist; also called the serosa notes: lined thoracic cavity and abdominopelvic cavity

Membrane

a thin sheet of tissue or layer of cells acting as a boundary, lining, pr partition in an organism.

abdominiopelvic cavity

abdominal cavity: digestive organs, spleen, kidneys;peritoneum pelvic cavity: bladder, rectum, reproductive organs; peritoneum.

parietal layer

lines the internal surface of the body wall, the more superficial or outer one

retroperitoneal organs

located behind the peritoneum

intraperitoneal organs

organs that are encircled by peritoneum and connected to the posteruir body wall by peritoneal sheets

parietal pericardium (pericardial sac)

outer layer of the pericardium

mesocolon

posterior mesentery of the large intestine

Meninges

- protects the delicate nervous tissue from the hard protective bone that encloses it. -three membrane layers

diaphragm

Large, flat muscle at the bottom of the chest cavity that helps with breathing

Visceral layer

Some of these membranes are two-layered, having one layer against the organ surface( such as the heart or lung) and one layer against a surrounding structure(forming, for example, the inner lining of the rib cage); there is only a thin film of liquid between them. in such cases, the inner layer, against the organ is called visceral layer.

MESENTERY (mes·en·ter·y/ˈmezənterē/)

an organ that attaches the intestines to the posterior abdominal wall in humans and is formed by the double fold of peritoneum. Notes: It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intestines, among other functions. contains: 1.blood vessel 2. lymphatic vessel 3. nerves

vertebral canal

assocaited viscera: spinal cord membranous lining: meninges

cranial cavity

associated viscera: brain membranous lining: Meninges (me·nin·ges/məˈninjēz/)

pericardium

the heart is enfolded in a two-layered membrane

visceral pericardium

the inner layer of the pericardium forms the surface of the heart itself