EYES

Definition: 
The eyeball is the organ of sight (vision.)

Location: Orbit of the skull.

Shape: Spherical.

Diameter: 2.5 cm (1 inch).

Structure of the eye:
The eyeball is composed of three coats (tunics), a lens, and two principal cavities

Coast (tunics) forming the wall of the eyeball:
1.    Outer / fibrous coat has two parts:-
        (a) The sclera is opaque and forms the posterior five-sixth of the eyeball. It is composed of dense fibrous tissue. It maintains the shape of the eyeball.
        (b) The cornea is transparent and forms the anterior one sixth of the eyeball.

2.    Middle / vascular coat has three parts :
       (a) The choroids, a thin pigmented layer. It is highly vascular and supplies nutrients and oxygen to the eye
       (b) The ciliary body, The thickened anterior portion that encircles the lens.
      (c) The iris, the most anterior portion of the vascular coat. It consists of pigment which gives the visible colour of the eye. Pupil is the round opening in the centre of the iris. It controlsthe amount of light to enter the eye.

3. Inner coat/Retina, the thin delicate inner layer of the eyeball. It is continuous with the optic nerve posteriorly.

The retina contains two types of photoreceptors:
      (a) Rods can respond to dim light and are responsible for night vision.
      (b) cones respond only to bright light and are sensitive to colour vision.

Layers of retina:
The retina is composed of ten layers

    outer pigment layer
    layer of rods and cones
    external limiting membrane
    outer nuclear layer
    outer plexiform layer
    inner nuclear layer
    inner plexiform layer
    ganglion cell layer
    optic nerve fibres layer
    internal limiting membrane


lens:
   (a) The lens is a transparent.biconvex structure. It is placed  between the an terior and posterior segments of the eye.
   (b)  it is enclosed in a lens capsule and held in place by the suspensory ligament.
   *the lens acts like a camera lens. Refracting and focusing light onto the retina.

Cavities of the eye:
The interior of the eye is separated by the lens into two cavities:
   1. anterior cavity-is bounded in front by the cornea and behind by the lens and iris. It is filled with a clear. Water fluid called aqueous humour
   2. posterior cavity-lies be hind the lens. Occupying posterior  4/5th of the eyeball. It is filled with a transparent jelly-like mass called vitreous humour.   

LIVER

The liver is the largest gland in the body, situated in the right hypochondrium andepigastric region.

Surfaces of the liver:

    Diaphragmatic surface : smooth, dome-shaped, lies against the inferior surface of the diaphragm.
    Visceral surface :  it is directed inferiorly and is covered with visceral peritoneum except in the fossa of the gallbladder and the porta hepatic.


The surface of the shows :

        Gastric impression,
        Duodenal impression,
        Colic impression,
        Right renal impression,
        Right suprarenal (adrenal) impression,
        Fossae for gallbladder and inferior venacava



 


















Lobes of the liver:
The right is divided into right and left lobes by fossae for the gallbladder and the inferior vena cava.

    The right lobe of the liver is a single large lobe.
    The left lobe of the liver is smaller and divided into quadrate and caudate lobes.


Structure of the liver:

    The liver is covered by Glisson’s capsule.
    The basic structural of the liver cell, called hepatocyte. Hepatocytes from layer one or two cells thick, forming anastomosing cords or plates. These plates are separated from each other by large vascular spaces known as liver sinusoids. Hepatic macrophages (kupffer cells) are present among the hepatocytes lining the sinusoids.
    Hepatocytes are arranged in hexagonal-shaped lobules. These structural units are called classical liver lobules. The center of each classical lobule is occupied by the central vein.
    Where 3 classical lobules contact each other a triangular spaces are demarcated, know as portal lobules with centrally located portal triads. Each portal triad contains a portal venule, a hepatic arteriole and a bile ductile.

JOINTS

Definition and the glenoid cavity of the scapula:
The shoulder joint is a synovial ball and socket joint between the head of the humerus

Type:
Synovial. Ball and socket. Multiaxial

Ligaments:
The shoulder joint is stabilized by a number of ligaments
1. transverse humeral ligament
2. coracohumeral ligament
3. glenohumeral ligaments

















Movements
The shoulder joint allows movement in all directions:
1. flexion
2. extension
3. abduction
4. adduction
5. medial
6. rotation
7. lateral rotation
8. circumduction

Elbow joint
Type: synovial. Hinge
Articular surfaces: trochlea of humerus with the trochlear notch of ulna, and capitulum of
humerus with head of radius
Ligaments: capsular, radial collateral and ulnar collateral
Movement: Flexion and extension.

Knee joint
The knee joint is the largest synovial joint in the body. It consists of:
1. the articulation between the femur and tibia
2. the articulation between the patella and the femur

External ligaments
The main ligaments are-
  1. collateral ligaments
  2. cruciate ligaments
  3. popliteal ligaments
  4. patellar ligament

Movements
Possible movements at knee joint are flexion, extension, lateral rotation and medial
rotation.
      

KIDNEYS

The kidneys are a pair of bean-shaped excretory organs in the posterior abdominal region.

Position:
The kidneys are retroperitoneal in the posterior abdominal region, one on each side of the vertebra column. They extend from the level of the 12th thoracic vertebra to the 3rd lumber vertebra. The right kidney is slightly lower than the left because of its relationship  with the liver.

Function of the kidneys:

    Excretion of metabolic waste products and foreign chemicals by formation of urine
    Regulation of water and electrolyte balances
    Regulation of body fluid osmolality and  electrolyte concentrations
    Regulation of arterial pressure
    Regulation of acid –base balance

Measurement:
Length: About 12cm
Width: 6: cm
Thickness: 3: cm

EXTERNAL FEATURES
Each kidney has:
1. Two pales-upper and lower
2. Two borders-medial and lateral
3. Two borders – anterior and posterior

Hilum
Write short note on: Hilum of kidney.
The hilum is a depression on the medial border border of the kidney. Internally, the hilum is continuous with the renal sinus.


STRUCTURES SEEN IN THE HILUM
    The renal vain
    The renal artery
    Renal pelvis
    Lymph vessels
    Nerves.


Renal pelvis:
It is the funnel-shaped superior end of the ureter .


RELATIONS OF THE KIDNEYS
Each of the kidneys is associated with different groups of structures:

RIGHT KIDNEY:
Superiorly-the right adrenal gland
Anteriorly-the right lobe of the liver, the duodenum and the hepatic flexure of the colon
Posteriorly-the diaphragm, and muscles of the posterior abdominal wall.

Left kidney:
Superiorly-the left adrenal gland
Anteriorly-the spleen , stomach , pancreas , jejunum and splenic flexure of the colon
Posteriorly-the diaphragm and muscles of the posterior abdominal wall

LUNGS

The lungs are a pair of respiratory organs situated on either side of the mediastinum surrounded by the right and left pleural cavities
Features:
1. two surface:
                     (a)  Costal surface
                     (b) Medial surface

2.three borders:
                     (a) Inferior border    
                     (b) Anterior border
                     (c) Posterior border

Root and hilum:
The root of the lung is a short. Broad pedicle that connects the medial surface of the lung to the mediastinum. It is formed by structures which either enter or come out of the lung at the hilum.

Right lung:
The right lung has three lobes and two fissures
The right lung is divided in to three lobes(superior, middle and inferior) by two fissures oblique and horizontal.

The medial surface of the right lung is related to a number of important structures such as:
1. Eparterial bronchus
2. hyparterial bronchus
3. superior pulmonary vein
4. inferior pulmonary vein
5. pulmonary artery
6. pulmonary ligament
7. oesophagus

Left lung:
Give a short anatomy of left lung
The left lung is smaller be cause the heart occupies the space left of the midline.

It has to lobes:
Superior and inferior. Separated by an oblique fissure.
1. the oblique fissure of the left lung is slightly more oblique than that of the right lung.
2. lingual of left lung is a tongue-like extension from the lower part of the superior lobe. 

Major structures related to the left lung:
The medial surface of the left lung is related to a number of important structures:
1. the heart
2. arch of the aorta(aortic arch)
3. thoracic aorta
4. oesophagus

HEART

The heart is a conical hollow muscular organ.

Position
 It is situated in the middle mediastinum.

Structure of the heart
*Anterior or sternocostal surface
*Inferior or diaphragmatic surface
*Posterior surface or base

  Borders of the heart
 1. Right border
 2. Inferior border, at the left extremity of which  is the apex.
 3. Left border, which separates the anterior and left surfaces of the heart.

Chambers of the heart
Mention the different chambers of the heart.

The heart has four chambers
right and left atria, and right and left ventricles. The tissue separating the two atria is the interatrial septum, and the separating the two ventricles is the interventricular septum.

Right atrium
It is the right upper chamber of the heart. It receives venous blood from the whole body through three vessels :
1. superior vena cava
2. Inferior vena cava
3. Coronary sinus, which returns blood from the walls of the heart itself.


Right ventricle
The right ventricle is a triangular chamber which receives blood from the right atrium and pumps it to the lungs through the pulmonary trunk and pulmonary trunk and pulmonary arteries.

Left atrium
The left atrium is a quadrangular chamber situated posteriorly. It receives oxygenated blood from the lungs through four pulmonary veins, and pumps it to the left ventricle through left atrioventricular orifice (mitral orifice).

Valves of the heart
Types of valves of the heart
For maintaining unidirectional blood flow through the heart, it contains four valves in its orifice :
1. tricuspid
2. pulmonary
3. mitral
4. aortic

HOME

The term anatomy is derived from the greek words meaning “to cat apart”
Because in anatomical studies the human body or its parts are dissected (cut up) to be axamined.

Definition of anatomy:
Anatomy is the study of the structure of the body parts and their relationships to one another

Subdivisions of anatomy:
Anatomy is a broad field with many subdivision


Gross macroscopic of anatomy:
gross or macroscopic anatomy is the large body structures visible to the naked eye.
Such as the heart. lungs and kidneys.

Regional anatomy:
regional anatomy is the study of all the structures (muscles. bores. blood  vessels. nerves etc) in a particular region of the body. Such as the abdomen or leg. are examined at the same time.

Systemic anatomy:
systemic anatomy is the study of the structure of the body system by system.
For example. when studying the   cardiovascular system. you would examine the heart and the blood vessels of the entire body

Surface anatomy:
surface anatomy is the study of the internal structures as relates to the overlying skin surface.

Radiographic anatomy:
radiographic anatomy  is the study of the internal structures as visualized by x-ray images or specialized scanning procedures.

The language of anatomy:
In order to achieve uniformity of description a set of terms are used to describe anatomy that have precise meaning. Use of these terms assumes the body in the anatomical position

Anatomical position:
anatomical position is a standard body position in which the palms facing forwards and the feet only slightly apart.