Hip

Constitutes the pelvic girdle
United with the vertebral column
Union of three parts that is marked by a cup shaped cavity (acetabulum) Ilium
•    Prominence of the hip
•    Superior border is the crest
•    Anterosuperior spine-projection at the anterior tip of the crest
•    Corresponding projections on the posterior part are the posterosuperior and posteroinferior iliac spines
•    Greater sciatic notch-located beneath the posterior part
•    Most is a smooth concavity (iliac fossa)
•    Posteriorly it is rough and articulates with the sacrum in the formation of the sacroiliac joint

Pubic bone

Anterior part of the innominate bone
Symphysis pubic-joining of the two pubic bones at the midline
Body and two rami 
•    Body forms one fifth of the acetabulum
•    Superior ramis extends from the body to the median plane: superior border forms the pubic crest
•    Inferior ramus extends downward and meets with the ischium
•    Pubic arch is formed by the inferior rami of both pubic hones

Ischium
    Forms the lower and back part of the innominate bone
    Body
•    Forms two fifths of the accrabulum
•    Ischial tuberosiry-supports the body in a sitting position
•    Ramus-passes upward to join the inferior ramus of rhe pubis; known as rhe obturator foramen

Pelvis

Fanned by the right and left hip bones, sacrum, and coccyx

Greater pelvis

o    Bounded by the ilia and lower lumbar vertebrae
o    Gives support to the abdominal viscera

Lesser pelvis

o    Brim of the pelvis corresponds to the sacral promontory
o    Inferior outlet is bounded by the tip of the coccyx, ischial tuberosities, and inferior rami of the pubic bones

Female pelvis

o    Shows adaptations related to functions as a birth canal Wide outlet
o    Angle of the pubic arch is obtuse

Male pelvis

o    Shows adaptations that contribute to power and speed
o    Heart-shaped outlet
o    Angle of the pubic arch is acute

Thigh

Femur-longest and strongest bone of the body
Proximal end has a rounded head that articulates with the acetabulum
Constricted portion-the neck
Greater and lesser trochanters
Slightly arched shaft; is concave posteriorly
o    Linea aspera-strengthened by this prominent ridge
o    Site of attachment for several muscles
Distal end has two condyles separated on the posterior side by the intercondyloid notch

Knee cap

Patella-sesamoid bone
Embedded in the tendon of the quadriceps muscle
Articulates with the femur

Leg

Tibia-medial bone
o    Proximal end has two condyles that articulate with the femur
o    Triangular shaft

    Anterior-shin
    Posterior-soleal line
    Distal-medial malleolus that articulates with the latus to form the ankle joint
Fibula-lateral bone
o    Articulates with the lateral condyle of the tibia but does not enter the knee joint
o    Distal end projects as the lateral malleolus

Ankle, foot, and toes

Adapted for supporting weight but similar in structure to the hand

Talus

o    Occupies the uppennost and central position in the tarsus
o    Distributes the body weight from the tibia above to the other tarsal bones
Calcaneus (heel)-Iocated beneath the talus
Navicular-located in front of the talus on the medial side; articulates with three cuneifonn bones distally
Cuboid-lies along the lateral border of the navicular bone

Metatarsals
o    First, second, and third p1etatarsals lie in front of the three cuneifonn bones
o    (2) Fourth and fifth metatarsals lie in front of the cuboid bone

Phalanges

o    Distal to the metatarsals
o    (2) Two in the great toe; three in each of the other four toes .

Longitudinal arches in the foot (2)

o    Lateral-fonned by the calcaneus, talus, cuboid, and fourth and fifth metatarsal bones
o    Medial-fonned by the calcaneus, talus, navicular, cuneifonn, and first, second, and third metatarsal bones

Transverse arches-formed by the tarsal and metatarsal bones

• This is the second cranial nerve (CN II) and is the nerve of sight.

The Palate

• The palate forms the arched roof of the mouth and the floor of the nasal cavities.
• The palate consists of two regions: the anterior 2/3 or bony part, called the hard palate, and the mobile posterior 1/3 or fibromuscular part, known as the soft palate.

The Hard Palate

• The anterior bony part of the palate is formed by the palatine process of the maxillae and the horizontal plates of the palatine bones.

• Anteriorly and laterally, the hard palate is bounded by the alveolar processes and the gingivae.
• Posteriorly, the hard palate is continuous with the soft palate.

• The incisive foramen is the mouth of the incisive canal.
• This foramen is located posterior to the maxillary central incisor teeth.
• This foramen is the common opening for the right and left incisive canals.
• The incisive canal and foramen transmit the nasopalatine nerve and the terminal branches of the sphenopalatine artery.

• Medial to the third molar tooth, the greater palatine foramen pierces the lateral border of the bony palate.
• The greater palatine vessels and nerve emerge from this foramen and run anteriorly into two grooves on the palate.

• The lesser palatine foramen transmits the lesser palatine nerve and vessels.
• This runs to the soft palate and adjacent structures.

Smooth Muscle

Light microscopic Structure:

cells - long - spindle shaped,  nucleus lies in the widest widest part of the fiber,  when the fiber contract the nucleus become folded, 30 - 200 µm long,between fibres lie endomycium

Electron microscopic structure:

 Mitochondria, ribosomes, golgi, rough EPR, myofilaments are present but no sarcomeres and no Z lines,thin filaments - actin and tropomyosin (7nm), thick filaments - myosin (17nmØ)

- intermediate filaments (10 nm)

- actin and myosin overlap more than in skeletal muscle and can therefore contract more

 A rudimentary sacroplasmic reticulum is present in the form of invaginations on the surface called caveolae , So there are no T-tubules,  Cells communicate through gap junctions.

Dense bodies

Filaments are attached to dense bodies which take the place of the Z line in skeletal muscle

There are two types of dense bodies - cytoplasmic and membrane

contains a percentage actinin (like the Z line)

dense bodies transmit contractile force to adjacent fibres

Arrangement:

Fibres can be single or in groups, normally arranged in sheaths,  In the GIT are 2 or 3 layers

Nerve supply:

2 types:

Where it is arranged in layers a few fibres are innervated together

impulse spread through the gap junctions between fibres (slow contraction)

In the iris and the vas deferens each fiber is individually supplied (quick contraction)

Internal Ear

• Osseous labyrinth: a complex system of cavities in the substance of the petrous bone.
• Membranous labyrinth: filled with endolymph, bathed in perilymph.

The Orbital Vessels

• The orbital contents are supplied chiefly by the ophthalmic artery.
• The infraorbital artery, the continuation of the maxillary, also contributes blood to this region.
• Venous drainage is through the superior orbital fissure to enter the cavernous sinus.

The Ophthalmic Artery

• This artery arises from the internal carotid artery as it emerges from the cavernous sinus.
• It passes through the optic foramen within the dural sheath of the optic nerve and runs anteriorly, close to the superomedial wall of the orbit.

The Central Artery of the Retina

• This is the one of the smallest but most important branches of the ophthalmic artery.
• It arises inferior to the optic nerve until it approaches the eyeball.
• It then pierces the optic nerve and runs within it to emerge through the optic disc.
• The central artery of the retina spreads over the internal surface of the retina and supplies it.

The Ophthalmic Veins

The Superior Ophthalmic Vein

• The superior ophthalmic vein anastomoses with the facial vein.
• It has no valves and blood can flow in either direction.
• It crosses superior to the optic nerve, passes through the superior orbital fissure and ends in the cavernous sinus.

The Inferior Ophthalmic Vein

• This begins as a plexus on the floor of the orbit.
• It communicates with the inferior orbital fissure with the pterygoid plexus, crosses inferior to the optic nerve, and ends in either the superior ophthalmic vein or the cavernous sinus.