স্পেশাল বিসিএস (স্বাস্থ্য) - লং কোর্স

Ovarian cortex is covered by the germinal epithelium which is made up of a single layer of cuboidal cells in younger age. 

Nerves directly related to humerus
Three nerves are closely related to the humerus and susceptible to injury following fracture/dislocation of the corresponding parts
a. Axillary nerve around the surgical neck
b. Radial nerve in the radial/spiral groove
c. Ulnar nerve behind the medial epicondyle

The barriers of an oocyte are
1. First barrier is formed by cells of corona radiata
2. Second barrier is formed by zona pellucida made of glycoproteins, ZP1, ZP2, and ZP3.
3. Third barrier is formed by vitelline membrane of oocyte itself

The recurrent laryngeal nerve is closely related to the inferior thyroid artery and any damage to it during surgery may result in hoarse ness of the voice. 

Injury to the external laryngeal nerve is more common because of its proximity to the superior thyroid artery. This leads to loss of tension in the vocal cord with diminished power and range in the voice. Patients, particularly those who use their voice professionally, must be advised that any thyroid operation will result in change to the voice even in the absence of nerve trauma. 

[Ref. Bailey & Love's 27th, Page 865] 

The adherence and attachment of blastocyst to the endometrium is referred to as implantation.
• Site: Normal site is posterior wall of the uterus close to the fundus
• Time: The process begins 6 7 days after ovulation and completed by 11 12 th day when the blastocyst is completely embedded in the stroma of the compact layer of endometrium.

Metanephros Gives rise to nephrons i.e. secretory/excretory part of the kidneys
• Bowman’s capsule
• Glomerulus
• PCT
• Loop of Henle
• DCT

Cremasteric muscle: 
Well developed in male, Derived from internal oblique & transversus abdominis
 Nerve supply: Genital branch of genitofemoral nerve (L1, L2)
 Action: Pull the testes, Cremester reflex, thermo regulation of testes
 Cremasteric reflex: Root value L1, L2

Exchange of gases such as oxygen, carbon dioxide, and carbon monoxide is accomplished by simple diffusion

• Immunological competence of the fetus begins to develop at around 3 months. By this time the fetus makes all the components of the complement
• Maternal IgG begins to be transported from the mother to the fetus at approx 14 weeks (3.5 months)
• Newborns begin to produce their own antibody, but adult levels are not reached until the age of 3 years

Structures piercing the diaphragm: 
1. Greater, lesser, and least splanchnic nerves pass by piercing the crus of diaphragm on the corresponding side
2. Hemiazygos vein pierces the left crus of the diaphragm
3. Left phrenic nerve pierces left cupola

Although the nail is an avascular structure, most of the nail-bed has rich vascular supply. 

Epithelium is an avascular structure, it receives nutrition from the underlying dermal capillaries. 

Cartilage receives nutrition from the perichondrium. 

Cornea receives nutrition by diffusion from the surrounding capillaries. 

[Ref. Junquira}

Hemophilia is an X-linked recessive trait.

In X-linked recessive disorders-
1. Affected cases are usually males carrying the gene.
2. Homozygous females can be affected, but this is rare.
3. Heterozygous females usually do not express the full phenotypic changes because of the paired normal allele.
4. Only females are carriers.
5. If a female has the allele (female carrier) with a normal male, off springs will be
    - 50% daughters carrier, 50% normal
    - 50% sons affected, 50% normal
6. If a male has the allele (affected male) with a normal female the off springs will be
   - All daughters carrier
   - All sons normal (no male to male

Common sites for peptic ulcers are the first part of the duodenum and the lesser curve of the stomach, but they also occur on the stoma following gastric surgery, in the oesophagus and even in a Meckel’s diverticulum, which contains ectopic gastric epithelium. In general, the ulcer occurs at a junction between diferent types of epithelia, in the epithelium least resistant to acid damage.

Birth defect, congenital malformation, and congenital anomaly are synonymous terms used to describe structural, behavioral, functional, and metabolic
disorders present at birth.

Susceptibility to teratogens varies with the developmental stage at the time of exposure. The most sensitive period for inducing birth defects is the third to eighth weeks of gestation, the period of embryogenesis. 

Autosomal dominant disorders: 
Skeletal
1. Marfan syndrome
2. Osteogenesis imperfect
3. Achondroplasia
4. Ehlar Danlos Syndrome
Nervous
1. Huntington’s disease
2. Neurofibromatosis
3. Myotonic dystrophy
4. Tuberous sclerosis
Urinary
1. Polycystic kidney disease
Metabolic
1. Familial hypercholesterolemia
2. Acute intermittent porphyria
Gastrointestinal
1. Familial adenomatous polyposis coli
Haematopoeitic
1. Von Willebrand disease
2. Hereditary spherocytosis

The Fallot’s tetralogy is the commonest congenital cyanotic heart disease.
This condition occurs due to combinations of four cardiac anomalies
1. Pulmonary stenosis,
2. Overriding of aorta (i e displacement of aortic orifice to the right to override the IV septum)
3. Ventricular septal defect ( and
4. Right ventricular hypertrophy
The resultant right to left shunting of blood leads to cyanosis