Master Embryology With Dr. Najeeb

1. What is gametogenesis and overview of gametogenesis in male and female. (00:01…02:46 min)

2. Basic concepts of meiosis: (02:47…29:19 min)

a. Homologous chromosomes, genes and alleles. (02:47…10:02 min)

b. Chromatids. (10:03…13:16 min).

c. Haploid and diploid chromosomes. (13:17…24:19 min)

3. Stages in first mitotic division (meiosis 1):

a. Synapsis of primary gametes. (24:20…29:29 min)

b. Crossing over. (29:30…31:52 min)

c. Chiasma. (31:53…35:36 min)

d. Alignment. (35:37…36:13 min)

e. Secondary gametes and first polar body. (36:14…43:24 min)

4. What is Second mitotic division (meiosis 2) and its stages. (43:24…49:09 min)

5. Overview of lecture. (43:24…51:51 min)

1. Introduction to Oogenesis (00:09…00:55 min)

2. Prenatal oogenesis (00:56…14:50 min)

a. Development of primordial germ cell into the primary oocyte (00:56…08:07 min)

b. Arrest of the primary oocyte at Diplotene stage of Prophase-I of Meiosis-I (08:08…14:50 min)

3. Postnatal oogenesis (14:41…28:00 min)

a. Maturation of primordial follicle into primary ovarian follicle and its features (14:51…18:59 min)

b. Formation of secondary follicle and its layers (19:00…22:14 min)

c. Graafian follicle and its arrest at metaphase of meiosis-II (22:15…28:00 min)

4. Ovulation and disintegration if fertilization does not occur (28:00…30:59 min)

5. Fertilization of secondary ovum and completion of meiosis-II (31:00…37:04 min)

1. Cell cycle and its phases with examples. (00:01…13:32min)

2. Brief comparison between interphase, mitosis and cytokinases. (13:33….17:31min)

3. Phases of mitosis: (17:31…30:41min)

a. Prophase. (19:41…24:22min)

b. Metaphase. (24:23…27:20min)

c. Anaphase. (27:21…28:47min)

d. Telophase. (28:48…30:41min)

4. What are G1 and G2 check points? (30:42…38:03min)

5. How the cell cycle progression is controlled? (38:04…55:30min)

1. Continuation of previous lecture “cell cycle and genes part 1” (progression of cell cycle). (0:01...18:22min)

2. Role of different factors in the development of cancer. (18:23...29:06min)

a. Proto-oncogenes. (18:23...25:18min)

b. Tumor suppressant genes. (25:19...27:28min)

c. Human papillomaviruses. (27:59...29:06min)

3. Function of p-53 in cell arrest, cell repair system and apoptosis. (29:07...44:13min)

4. Defect in p-53 and cancer. (44:14...45:04min)

5. Role of p-53 in different checkpoints during the cell cycle. (45:05...48:21min)

1. Steps and structures involved in release of Gonadotropin hormones (00:01...15:24min)

2. Average menstrual cycle days and clinical correlations (15:25...18:56 min)

3. Conversion of Primordial follicle to primary follicle (18:57...26:45 min)

4. Detailed overview of Oogenesis (26:46...37:48 min)

5. FSH and its role in maturation of primary follicle to graafian follicle containing secondary follicle (37:49...49:26 min)

a. Discussion about formation and function of zona pellucida (39:58...43:36 min)

b. Function of granulosa and theca cells (43:37...47:12)

6. Proliferative phase of the menstrual cycle (49:27...55:07 min)

1. Negative Feedback of Estrogen and concept of atretic follicle (1:22…6:33 min)

2. Positive feedback of estrogen (6:34…10:51 min)

3. LH surge and its influence on graafian follicle (10:52…14:02 min)

4. Rupture of graafian follicle and release of ovum containing corona radiata (14:03…17:00 min)

5. Formation of corpus luteum (Luteinization) and release of progesterone (17:01…22:23 min)

6. Effects of progesterone on uterine wall /Secretory phase (22:24…25:14 min)

7. Degeneration of corpus luteum leading to menstrual phase (25:15…35:25 min)

8. Beginning of a new reproductive cycle (35:26…38:07 min)

9. Fertilisation of ovum and its implantation to uterine wall (38:08…42:57 min)

10. Release of Human chorionic gonadotropin hormone and its effect on corpus luteum (42:58…49:15 min)

11. Conclusive summary of the entire lecture (49:16…55:37 min)

1. Definition of fertilization (0:01…04:00 min)

2. Common site of fertilization and parts of fallopian tube (04:01…06:58 min)

3. Steps involved in Transport of ovum to the site of fertilization (06:59…15:14 min)

4. Steps and factors involved in transport of sperm to fertilization site (15:15…31:44 min)

5. Changes in sperm before fertilization and process of capacitation (31:45…37:10 min)

1. Sperm and zona pellucida binding with the resulting acrosome reaction (0:01…06:53 min)

2. Sperm and oocyte binding and explanation of the zona reaction (06:54…13:35 min)

3. Fusion of sperm with ovum and release of genetic material into an ovum (13:36…15:50 min)

4. Completion of meiosis II and creation of definitive ovum (15:51…19:00 min)

5. Interaction between integrins and disintegrins (19:01…20:44 min)

6. Overview of the response of the egg to sperm fusion (20:45…22:07 min)

7. Metabolic activation of the ovum (22:08...24:00 min)

8. Intermingling of maternal with paternal nuclei and establishment of diploid number of chromosomes (24:01…33:35 min)

9. Detailed overview of the main results of fertilization with the concept of chromosomal sex determination 33:36…36:07 min)

1. 1st Cleavage of fertilized ovum leading to two cell stage of zygote at day 2 of fertilization (0:01…06:06 min)

2. Formation of morula at day 3 of fertilization (06:07…8:25 min)

3. Process of compaction and concept of inner and outer cell mass (8:26…12:25 min)

4. Differentiation of morula into blastocyst and formation of trophoblast and embryoblast – day 4 of fertilization (12:26...17:48 min)

5. Detailed revision of female reproductive cycle to explain blastocyst implantation (17:49…27:19min)

1. Structure of endometrium (0:00...5:30mins)

2. Implantation of the blastocyst in endometrium (5:30...10:10mins)

3. Progressive changes in cytotrophoblast in second week (10:11...26:16mins) a. Rule of two (10:12...12:01mins)

b. Syncytiotrophoblast (12:02...15:40mins)

c. Lacuni (15:41...17:40mins)

d. Primary development of uteroplacental circulation (17:41...21:00mins)

e. Gestational little bleeding(21:01...26:16mins)

4. Embryonic development in the second week (26:17...40:01mins)

5. Review of lecture (40:02...43:10mins)

6. Rule of two (43:11...44:05mins)

1. How bilaminar disc converts to trilaminar disc during 3rd week (0:01...5:10mins)

2. Process of gastrulation (gastula formation) (5:11...8:57mins)

3. Primitive streak and node formation (8:58...11:34mins)

4. Primitive groove and pit (11:35...15:25mins)

5. Hypoblast replaced by endoderm (15:26...22:00mins)

6. Mesoderm development from epiblast (22:01...24:27mins)

7. Epiblast transforming into ectoderm (24:28...26:34mins)

8. E-cadherins functions (26:35...28:32mins)

9. Process of cells moving down through primitive node (28:33...35:29mins)

10. Cells moving towards primitive pit forming tube (35:30...38:58mins)

11. Notochordal plate formation (38:59...43:25mins)

12. Absence of mesoderm in three specific points of trilaminar disc (43:26...45:23mins)

13. Buccopharyngeal membrane (45:24...46:13)

14. Areas developing into mouth and anus (46:14...47:44mins)

15. Notochordal area characteristics (47:45...49:26mins)

16. Neuroenteric canal formation (49:27...55:17mins)

1. Review of Development upto 3rd week (trileminar disc) part 1(00:01...2:17mins)

2. How notochordal process is developed to definitive notochord (2:18...8:00mins) a) 1st step; notochordal process and endoderm disintegrates (2:18...4:39mins)

b) 2nd step; notochordal plate intercalated with endoderm (4:40...6:30mins)

c) 3rd step; a solid mass of notochordal cells (6:31...8:00mins)

3. Definitive notochord and its role (8:01...12:30mins)

4. Brief explanation of steps involved in the formation of end structure of trilaminar disc at the end of 3rd week (12:31...20:36mins)

5. Trilaminar disc will be laterally folded and fuse together eventually (20:37...23:56mins)

6. How these three layer will fold into primitive baby structure (23:57...26:17mins)

7. Steps involved in completing gastrulation by the end of 3rd week (26:18...28:04mins)

1. Teratogenesis during gastrulation (0:01...3:32mins)

2. Teratogenesis affects of alcohol causing holoprosencephaly (3:33...21:05mins)

3. Factors causing caudal mesoderm dysgenesis (21:06...34:30mins)

4. Situs inversus during gastrulation (34:31...42:00mins)

5. Additional problems related to sinus inversus (42:01...50:04mins)

6. Karatageners syndrome (50:05...51:11mins)

1. General concept of cardiovascular system developing in an embryo (0:01...6:34mins)

2. Process of vasculogenesis (6:35...12:36mins)

3. Angiogenesis taking place after vasculogenesis in developing vascular system of embryo (12:37...15:00mins)

4. Development of arterial system (15:01...40:25mins)

a. Pharyngeal arches formation (15:02...25:35mins)

b. Transformation of embryological structures into vasculature of head, neck and upper part of thorax (25:36...28:18mins)

c. Mnemonic to remember the development of pharyngeal arches to complete vasculature system (28:19...40:25mins)

5. Vagus nerve branches to recurrent laryngeal nerve (40:42...47:55mins)

6. Abnormality related to the development of aortic arch (47:56...53:10mins)

1. Coarctation of aorta (0:01...4:23mins)

2. Problem related to coarctation of aorta (4:24...8:08mins) />3. Prescapular anastomosis connection to the intercostal arteries (8:09...9:25mins)

4. Clinical presentation in the patient with coarctation of aorta (9:26...11:17mins)

5. Collateral circulation (11:18...12:06mins)

6. Treatment to the coarctation of aorta (12:07...12:17mins)

7. Manifestation and risk factors in the patient (12:18...14:27mins)

8. Vasculature development of the other arteries in the body (14:28...20:53mins)

9. Explanation of the derivatives of vitelline arteries (20:54...29:41mins)

10. Derivatives of the post natal umbilical arteries (29:41...33:00mins)

1. Development of venous system in the fetus (0:01...3:57mins)

2. Sinus venosus as the input system in developing heart of fetus (3:58...6:36mins)

3. Initial design of venous system when developing (6:37...8:52mins)

4. Why venous system in the right side develops more (8:53...12:50mins)

5. Development of vitelline system (12:51...18:59mins)

6. Portal vein formation (19:00...21:03mins)

7. Functions of portal vein and why its named portal (21:04...22:49mins)

8. How hepato cardial channel leads to sinus venosus (22:50...26:05mins)

9. Main derivatives of vitelline system (26:06...30:00mins)

10. How umbilical veins developed(30:01...37:20mins)

11. Formation of ductus venosus and its purpose( 37:21...46:56mins)

12. Vitelline and umbilical vein remnant (ligamentum teres) (46:57...50:20mins)

13. Dutus venosus transforming to ligamentum venosus (50:21...51:31mins)

14. Review of the lecture (51:32...55:16mins)

1. Common cardinal vein formation (0:01...1:15 mins)

2. Extensive modification related to cardinal system (1:16...3:41 min)

3. New cardinal systems development (3:42...5:35 mins)

4. New channel develops from anterior cardinal system (5:36...8:10 mins)

5. Development of superior vena cava (8:11...8:47 mins)

6. How left sub-calavian vein is formed (8:48...9:00 mins)

7. Anomaly related to the development superior vena cava (9:01...15:32 mins)

8. Hemiazygos and azygos vein formation (15:33...20:58 mins)

9. Development of Inferior vena cava developing from the cardinal system (20:58...24:30 mins)

10. How last part of the inferior vena cava derived from sacro cardinal system (24:31...27:15 mins)

11. How is blood shunted from the posterior cardinal vein to anterior part? (27:16...28:46 mins)

12. Review of the lecture (28:47...33:26 mins)

1. Parts of the concept (0:00...1:43mins)

2. Normal fetal circulation (1:44...21:48mins)

3. Review of normal fetal circulation (21:49...23:08mins)

4. Changes in fetal circulation after birth (23:09...35:37mins)

5. Changes converting the prenatal circulatory pattern to post-natal circulatory pattern (35:38...39:59mins)

6. Post-natal remnants of fetal circulatory components (40:00...43:38mins)

7. Patent ductus arteriosus (43:39...45:35mins)

8. Treatment of patent ductus arteriosus (45:36...46:23mins)

1. Overview of Lecture Contents (00:00 … 01:00 mins)

2. Review of process of Fertilization (01:01 … 11:44 mins)

3. Review of Formation of Blastocyst and its Structure (11:45 … 17:18 mins)

4. Review of Stages of First Week of Human Embryogenesis (17:19 … 22:08 mins)

5. Review of Process of Implantation (22:09 … 30:23 mins)

6. Embryological Structures leading to Formation of Nervous System (30:24 … 58:00 mins)

a. Formation of Bilaminar Disc (30:25 … 33:33 mins)

b. Prechordal Plate (33:34 … 35:05 mins)

c. Primitive Streak and Formation of Notochord (35:06 … 41:18 mins)

d. Formation of Neural Plate (41:19 … 46:00 mins)

e. Formation of Neural Groove, Neural Folds and Neural Tube (46:01 … 54:01 mins)

f. Origin of Neural Crest Cells (54:02 … 58:00 mins)

7. Importance of Folic Acid in closing of Neuropores (58:01 … 01:00:06 mins)

1. Brief discussion on defects associated with failure of Posterior Neuropore closure (00:00 … 01:22 mins)

2. Derivatives of Neural Tube and their Development (01:23 … 42:22 mins)

a. Primary Vesicles (01:24 … 05:48 mins)

b. Lamina Terminalis (05:49 … 10:12 mins)

c. Secondary Vesicles and structures derived from them (10:13 … 21:21 mins)

d. Structures derived from Diencephalon (21:22 … 25:49 mins)

e. Structures derived from Telencephalon (25:50 … 26:52 mins)

f. Formation of Spinal Cord structures by Alar & Basal Plate of Neural Tube (26:53 … 36:56 mins)

g. Arrangement of Motor and Sensory Nuclei in Brainstem (36:57 … 42:22 mins)

3. Derivatives of Neural Crest Cells and their Development (42:23 … 51:53 mins)

a. Melanocytes (42:23 … 43:36 mins)

b. Pia and Arachnoid Matter (43:37 … 44:48 mins)

c. Sensory and Autonomic Ganglia (44:49 … 45:54 mins)

d. Bones of Neurocranium (45:55 … 46:31 mins)

e. Adrenal Medulla (46:32 … 47:13 mins)

f. Parafollicular C Cells of Thyroid (47:14 … 48:08 mins)

g. Odontoblasts (48:09 … 48:39 mins)

h. Cono-truncal Cushions and Aortopulmonary Septum of Heart (48:40 … 49:28 mins)

i. Schwann Cells (49:29 … 51:53 mins)

1) Basic concept about Mesoderm and how the development of the Musculoskeletal system occurs through the trilaminar disc in embryo? (00:00 ... 13:22 mins)

2) Concept about the development of the skull, Vertebrae and limbs via the changes in the neural tube, mesoderm and ectoderm. (13:23 ... 32:58 mins)

3) Detailed explanation of the development of the skull in embryo. (32:59 ... 52:18 mins)

1) Continuation of previous part “Musculoskeletal Development part 1” development of skull.(00:00 ... 14:14 mins)

2) Clinical correlates related with the development of skull in embryo. (14:15 ... 26:01 mins)

3) Detailed explanation on development of limbs in embryo. (26:02 ... 49:00 mins)

4) Clinical correlates related with the development of limbs in embryo. (49:01 ... 59:18 mins)

1) Detailed explanation of the development of vertebral column in embryo. (00:00 ... 14:32 mins)

2) Clinical relevance of the development of vertebral column in embryo. (14:33 ... 20:06 mins)