Arcade Academy

🧬 1️⃣ Totipotent Cell —

📌Totipotent cell এমন কোষ, যা থেকে -
👉 একজন সম্পূর্ণ মানুষ
👉 সব supporting structure (placenta, amnion, chorion) সবকিছুই তৈরি হতে পারে।

🕰 কখন থাকে?
Zygote
2-cell stage
4-cell stage
8-cell stage (early blastomere)

🧑‍⚕️ Clinical correlation -

Identical twins (monozygotic twins)
➡️ early totipotent stage-এ embryo split হলে হয়।

🌿 2️⃣ Pluripotent Cell —

📌 Pluripotent cell এমন কোষ, যা থেকে -

👉 শরীরের সব ধরনের কোষ (ectoderm, mesoderm, endoderm) তৈরি হতে পারে

❌ কিন্তু placenta বা extra-embryonic structure না।

🕰 কোথায় থাকে?
Inner Cell Mass (ICM) of blastocyst
Embryonic stem cells

🧠 Clinical & research value -

Stem cell therapy
Regenerative medicine
Spinal cord injury Diabetes research

🌾 3️⃣ Multipotent Cell
📌 Multipotent cell সীমিত কিছু কোষে রূপান্তরিত হতে পারে—
👉 একই Lineage-এর মধ্যে।

🕰 কোথায় থাকে?
Adult stem cells
Bone marrow
Mesenchymal stem cells

🩸 Classic example -
Hematopoietic stem cell →
RBC
WBC
Platelet

- First year

Metabolic Pathways Occurring in Mitochondria

Mnemonic: King COBRA

K = Ketogenesis
C = Carboxylation of pyruvate (to oxaloacetate)
O = Oxidation of pyruvate (to Acetyl CoA)
O = Oxidative deamination
B = Beta-oxidation (fatty acid breakdown)
R = Respiratory chain (ETC)
A = tcA cycle

Metabolic Pathways in Both Mitochondria & Cytoplasm

Mnemonic : HUG

H = Heme synthesis
U = Urea cycle (mainly in cytoplasm)
G = Gluconeogenesis (mainly in cytoplasm)

■■Week-by-Week Embryology ■■

■■Week 1 – Fertilization & Implantation ■■

Fertilization (zygote formation)

Cleavage and morula formation

Blastocyst formation

Implantation starts

Nickname: Week of Ones
(single cell → zygote, single cavity → blastocyst)

■■Week 2 – Bilaminar Disc Formation■■

Epiblast and hypoblast form

Amniotic cavity and yolk sac form

Implantation completes

Nickname: Week of Twos

■■Week 3 – Gastrulation & Trilaminar Disc■■

Formation of three germ layers:
Ectoderm, Mesoderm, Endoderm

Primitive streak appears

Notochord forms

Neurulation begins

Nickname: Week of Threes

■□■ Medicine Made Super Easy (MMSE)
■□■ Neurology- Davidson

■Myelin sheath of PNS is formed by Schwann cells
PSC (P= PNS + SC= Schwann Cell)

■Myelin sheath of CNS formed by Oligodendrocytes
COLI ( C= CNS + Oli = Oligodendrocyte)