Special Embryology

Urogenital system

development of urinary bladder :

Mesonephric duct divide primitive urogenital sinus into :

vesicourethral part (  upper )

definitive urogenital duct ( lower )

Urinary bladder derivative from :

1 – Vesicourethral  canal  of coloaca ( major )  [ endoderm ]

2 – Apex derived  from   →   Allantose ( proximal part )  [ endoderm ]

note distal part of allantois  give  median umbilical ligament

3 – trigone of bladder  developed from   →   mesonephric duct    [ mesoderm ]

Note  the base of bladder ( rose , , most sensitive , corregated , rich of blood supply )

due to their origin from mesoderm 

development  of ureter :

mesonephric duct give    →       ureteric  bed  (with metanephric cap wich rise  upward to abdomen )

ureteric bed extends above  &  opend direct into trigon

1 – definitive of urogenital:   [ mesoderm ]

pelvic part : lower of prostatic urethra & membranous part of urethra

phalic part : give  →  penil urethra

2 – vasicourethral canal  [ endoderm ]   →   upper part of prostatic urethra ( at level of ejaculatory duct )

development of gonads :

in different stages [ ovary or testes ] :

1 – genital ridge : medial part  of  mesonephrus ____ capsul (  tunica albugenia ) of testes  stroma  & septae

2 – coelomic  epithelium [ mesoderm ] :  sex  cord ( sertoli ) seminephrus tubules & rete testes

3 – primordial  germ  cell [ endoderm ] : spermatozoa  

descent  of  testes :

  • it s develops in the abdomen then descends
  •  reach deep inguinal ligament  ( internal descend ) at  7th month
  •  it migrates in the inguinal canal at 8th month

causes of descent :

  1. internal  descent  ( upper part of abdominal wall grow faster than lower part )
  2. rise of  intraabdominal  pressure ( growth & enlarged of abdominal organs )
  3. shortness ( during growth ) of gubernaculm  ( fibrous band attatch to scrotum )

development of the ovary :

1 – the same as the testes

2 – gives follicular cells instead sex cord

3 – migrating from yolksac   ⇒  gives oogonia wich

Divided into masses called primary follicle  OVA

Descent of ovary

Develop in the abdomen  it undergoes  internal  descent to reach the pelvic

The gubernaculums becomes ovarian ligament & round ligament

Development of vagina :

Upper third of the vagina developed from the uterovaginal canalmesoderm ]

Lower 2 third developed from paramesonephric duct ( mullerian duct )

[ considered endoderm ]

Development of external genitalia :

(  female )

Genital tubercle     form       ⇒  , clitoris

Genital fold    form   ⇒   , labia  minora

Genital swellings     form   ⇒   , the  two  labia  majora

( Male )

Genital tubercle   form   ⇒  , glans penis

Migration of ectodermal cells at the tip of the glans phallus    form   ⇒    Distal end of penil urethra

Genital & scrotal swelling fuse together to form       ⇒    scrotum

Phallus ascend with genital membrane     form     ⇒    urethra

Note  All are  originated  from endoderm except distal part of urethra in glans penis are ectoderm





What is pharmacodynamics

Mode of action of drug

Properties of action selectivity, affinity, structure activity relationship, chirality

Classification of receptor

Different between enzyme incorporated receptor & cytokine receptor

Types of intracellular second messenger

Types of drug response

What is potency, efficacy & it is related to drug action

Clinical important of IT

Causes increase responsiveness & causes reduce responsiveness ( tolerance)

Types of tolerance

Different between desensitization & hypersensitivity

Comparison between agonist & antagonist

Types of agonist

Types of antagonist

Factors modifying drug action

General Pharmacology

What is the pharmacology, PK ,PD

What is the different between  pharmacotherapeutics  & toxicology branch of pharmacology

When should be describe ( tablets, enema, drops or gels)

Comparison between routes of drug intake

The relationship between routes of drug intake  & health status of patient

Some drugs  have (  local  \  systemic  effects)  some are given  ( limited dose \  small amount)

What is bioavailability?

The relationship between routes & bioavailability of drugs

Absorption of drug

Comparison between active & passive transfer

The different between filtration & simple diffusion

The different between facilitated diffusion & active transport

Factors affect absorption of drug

Volume of Distribution & its related to plasma protein binding ( AGP, albumin, lipoprotein)

Factors affecting distribution of drug


What is Hemoprotein

Structure of Hemoprotein

What is porphyrins included in Heme biosynthesis

Formation of Heme ( all steps )

The site of Heme formation

Key regulatory enzyme in Heme biosynthesis

Distribution of side chain in porphyrins

Different between porphyrins & porphyrinogen

Effect of drug on ALA synthase

Porphyrias definition, types, clinical manifestation, treatment

Degradation of Heme , the occurrence site

Different between bilirubin & biliverdin

UDP & its role in Heme degradation

The only reaction in the body produce monoxide

Daily bilirubin formation

Distinguished between urobilinogen, urobilin, urochrom

Jaundice definition, causes, types, effects


Comparison between direct indirect bilirubin

Urobilinogen, bilirubin in urine are important clinical indicators


One of two regulatory [control] system in our body

Division of Nervous System ( anatomical, physiological )

Structural unit,  functional unit of Nervous System


Types & subtypes , different between somatic & autonomic reflex arc

RECEPTORES  definition, function, classification (& subtypes), properties

SENSORY CODE  Coding of sensory information

( intensity, modality, locality discrimination)

SYNAPS  definition classification & its types

Physiological Anatomy of SYNAPSE

Mechanism of Synaptic transmission ( EPSP, IPSP )

3 WAYS to removal neurotransmitter

Inhibition of Synaptic transmission (presynaptic, postsynaptic)

NEUOROTRANSMITTER  definition, properties, types ( 2 major groups ), effects of drug

NEURAL POOL    definition, arrangement of neurons , resulting phenomena, renshaw cell inhibitory system

Somatic sensation classification based on ( types, sites, pathways, center)


Definition, receptors ( nature, distribution, types, mechanism, adaptation)

Pathways of each type of Pain

Comparison between 2 types of cataneous pain

Pain control system


receptor, nature, types, pathway


Crude ( Non discriminative ) receptor, pathway

Fine ( discriminative ) receptor, types, pathway


( pressure,, tension,, vibration,, position,, movement )

[ meaning, receptor, tasted by ]

SENSORY AREA OF CEREBRAL CORTEX ( somatic & somatic association area )

HEADACHE   definition, pain sensation structure, types, mechanism, main causes.

SPINAL CORD   function, reflexes

STRECH  REFLEX   definition, pathway, receptor, types, properties,

Supraspinal centers affect stretch reflex

Clinical important & function of the stretch reflex


Comparison between motor tetanus & reflex tetanus

Causes of abnormal planter \ abdominal reflex

Functions of gama motor neuron

Stimulation of muscle spindle

Clasp-knife Spacticity   –    Lengthening reaction

Some sensory disturbance :

HYPERALGESIA      ( definition, types)

SYRINGOMYELIA   ( definition, effects, common site )


POLYNURITIS          ( definition, causes, manifestation )


Gene Expression

What is Gene Expression

What is Gene ?

Active chromatin & non active chromatin

The Differences between prokaryotic & eukaryotic of genetic information

DNA structure & organization

Central Dogma

Cell cycle

Major features of structure & function of human Mt DNA

Comparison between eukaryotes & prokaryotes

Regulation of eukaryotic gene expression intracellular & intercellular signals ( HREs,  SRE)




Mechanism ( all steps initiation, elongation, termination )

Comparison between prokaryotic & eukaryotic

Proteins involved in DNA replication

Enzymes involved in DNA replication require ATP

Types of DNA polymerases ( comparison between those in eukaryotes & prokaryotes)

supercoiling & its repairing enzyme which enzyme require ATP involved in DNA replication

reverse transcriptase

replication bubble replication fork

comparison between leading & lagging strand

mechanism of action of primase, telomerase

comparison between eukaryotic & prokaryotic DNA polymerase

( comparison in each one )

drugs , analogs  affecting  replication

DNA repair ( definition, mechanism, types & subtypes )




Requirements , types of RNA

Types of promoter ( in both prokaryotic & eukaryotes )

RNA polymerase ( only one type in prokaryotic & 3 types in eukaryotic)

Mechanism  ( all steps initiation, elongation, termination in both eukaryotic & prokaryotic )

Requirement of mRNA synthesis in eukaryotes

RNA polymerase II inhibited  by a- Amanitin treated by active carbon

Comparison between rRNA in both prokaryotic & eukaryotic

Inhibitors of transcription

RNA synthesis modification ( post-transcriptional modification)

Enhancers ( differs from promoter ,  has important role in Transcription )




TRANSLATION ( protein synthesis )



Mechanism (All steps,  initiation,  elongation,  termination in both prokaryotes & eukaryotes)

Inhibitors of protein synthesis

Post-translational modification of polypeptide chain


( protease, lysosome )

MUTATION ( definition, causes, types & subtypes )



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