Skip to main content

Renin Angiotensin Mechanism.

Body Cavities

 Introduction to the Human Body: Body Cavities

Introduction:

  • Human beings are the most complex of all the living organisms.

  • Human body contains many organs which work in an organized manner for an efficient working of the human body.

  • The study of human body is divided broadly in two divisions,

    • Anatomy

    • Physiology.

  • Human Anatomy is the branch of science that deals with the study of structures of different body parts.

  • Human Physiology is the branch of science that deals with the study of functions of different body parts.

Human Anatomy: Study of Structure.

Human Physiology: Study Of Functions.

Body Cavities:

  • These are spaces in the body that protect, separate and support the internal organs of the body.

  • The body cavities are mainly divided into two types,

    • Dorsal Body Cavities.

    • Ventral Body Cavities.

  1. Dorsal Body Cavities:

  • They are present on the dorsal side of the body.

  • They are comparatively smaller as compared to the ventral body cavities.

  • They are classified as,

    • Cranial Cavity.

    • Vertebral Cavity.

  • Cranial Cavity:

    • It contains Brain.

    • Boundaries are formed by the bones of the skull (Fig. 1.1):

      • Anteriorly —1 frontal bone

      • Laterally — 2 temporal bones

      • Posteriorly — I occipital bone

      • Superiorly — 2 parietal bones

      • Inferiorly — I sphenoid and 1 ethmoid bone and parts of the frontal, temporal and occipital bones.

Fig. 1.1

  • Vertebral Cavity:

    • It contains “Spinal Cord.”

    • Boundaries:

      • Are made by bones of the vertebral column i.e. by vertebrae  and the intervertebral discs between the bodies of the vertebrae.

  1. Ventral Body Cavities:

  • They are present on the ventral side of the body.

  • They are much larger in size as compared to the dorsal body cavities.

  • They are further classified as followings,

    • Thoracic Cavity

    • Abdominal Cavity.

    • Pelvic Cavity.

  • Thoracic Cavity: 

    • It is formed by,

      • Anteriorly — the sternum and costal cartilages of the ribs

      • Laterally — 12 pairs of ribs and the intercostal muscles

      • Posteriorly — the thoracic vertebrae and the intervertebral discs between the bodies of the vertebrae.

      • Superiorly — the structures forming the root of the neck

      • Inferiorly — the diaphragm, a dome-shaped muscle.

    • Contents

      • The main organs and structures contained in the thoracic cavities are (Fig. 1.2):

        • the trachea, 

        • 2 bronchi, 

        • 2 lungs

        • the heart, 

        • aorta, 

        • superior and inferior vena cava,

        • numerous other blood vessels

        • the oesophagus

Fig. 1.2

  • The thoracic cavity is divided into three parts,

    • Pleural Cavity: One around each lungs, Contains fluid.

    • Pericardial Cavity: Around heart, Contains fluid.

    • Mediastinum: Central part extends from sternum to vertebral column and from first rib to diaphragm, contains all organs of thoracic cavity except lungs.

  • Abdominal Cavity:

    • This is the largest cavity in the body and is oval in shape (Fig 1.3).

    •  It is situated in the main part of the trunk and its boundaries are:

      • Superiorly — the diaphragm, which separates it from the thoracic cavity 

      • Anteriorly — the muscles forming the anterior abdominal wall 

      • Posteriorly —the lumbar vertebrae and muscles forming the posterior abdominal wall 

      • Laterally — the lower ribs and parts of the muscles of the abdominal wall 

      • Inferiorly — the pelvic cavity with which it is continuous.

Fig 1.3

The abdominal cavity is divided into the nine regions shown in Figure 1.4. 

Figure 1.4

  • Contents

    • the stomach, 

    • small intestine and most of the large intestine

    • the liver, gallbladder, bile ducts and pancreas.

    • the spleen

    • 2 kidneys and the upper part of the ureters

    • 2 adrenal (suprarenal) glands

    • numerous blood vessels

    • lymph vessels,

    • nerves

    • lymph nodes.

  • Pelvic Cavity:

    • The pelvic cavity is roughly funnel shaped and extends from the lower end of the abdominal cavity (Fig 1.4). 

    • The boundaries are:

      • Superiorly — it is continuous with the abdominal cavity 

      • Anteriorly — the pubic bones 

      • Posteriorly — the sacrum and coccyx 

      • Laterally — the innominate bones 

      • Inferiorly — the muscles of the pelvic floor.

Fig 1.4

  • The pelvic cavity contains the following structures: 

    • sigmoid colon, rectum and anus 

    • some loops of the small intestine 

    • urinary bladder, lower parts of the ureters and the urethra

    •  in the female, the organs of the reproductive system: the uterus, uterine tubes, ovaries and vagina.

    • in the male, some of the organs of the reproductive system: the prostate gland, seminal vesicles, spermatic cords, deferent ducts (vas deferens), ejaculatory ducts and the urethra.

Commonly Asked Questions:

  1. Enlist different body cavities along with their locations.

  2. Write in short about,

    1. Thoracic Cavity.

    2. Abdominal Cavity.

    3. Pelvic Cavity.
Labels:

Popular posts from this blog

Rate of Drying Curve.

  Definition Drying is defined as the removal of liquid from a product usually with application of heat. Rate of Drying Curve. Drying process can be divided into three periods Initial Adjustment Period. Constant drying rate period. First falling drying rate period. Second falling rate period. Initial Adjustment Period (A-B): Also called the “ Heating up” period . In this period the substance gets heat and increases in temperature. Drying has not yet started. Constant drying rate period (B-C): During this period the temperature of the solid and the rate of drying remain constant. The moisture evaporating from the surface is replaced by water diffusing from the interior of the solid at a rate equal t o the rate of evaporation.  The moisture content at the end of constant rate (point C) is referred to as the critical moisture content (CMC).  At CMC, dry spots start appearing and drying rate starts falling . First falling drying rate period (C-D): This period is also called the period of
Read more

Heat Exchangers and Heat Interchangers.

  In pharmaceutical industries many types of equipments are used for transfer of heat, they can be classified as follows, Heat Exchangers. Heat Interchangers. Heat Exchangers: These devices are used for transferring heat from a fluid (Hot Gas or Steam) to another fluid (Liquid) through a metal wall. Heat Interchangers: These devices are used for transferring heat from a One liquid to another liquid or one gas to another gas through a metal wall. HEAT EXCHANGERS; The equipment used for heat transferring are known as heat exchangers. Some of the processes that involves heat transfer in pharmaceutical industries are: Preparation of starch paste (in steam jacketed kettle). Crystallization. Evaporation. Distillation.  Classification of heat exchangers On the basis of transfer of heat, heat exchangers are classified as: Direct transfer type:  The hot and cold fluids are separated by a metal wall through which the heat is transferred from hot fluid to cold fluid. E.g. shell and tube heater, 
Read more

Flash Distillation.

  Principle: When a hot mixture is allowed to enter from a high-pressure zone into a low pressure zone, the entire liquid mixture is suddenly vaporized. This process is known as flash vaporization .  During this process, the chamber is cooled.  The less volatile fraction is condensed and the more volatile component remains in the vapor phase .  This process requires time, hence liquid and vapor are kept in intimate contact until equilibrium is achieved. Flash distillation is also called equilibrium distillation because separation of two liquids takes place when liquid and vapor phases are at equilibrium. Equipment used for Flash Distillation: Construction: It consists of a pump, which is connected to a feed reservoir.  Pumps help in pumping the feed into the heating chamber.  The heating chamber is heat supplied by steam.  The other end of the pipe is directly introduced into the vapor-liquid separator through a reducing valve.  The vapor outlet is provided at the top of the separato
Read more