Reproduction — Mitosis, Meiosis & Development

Mitosis (somatic cell division):

PMAT: Prophase → Metaphase → Anaphase → Telophase

Result: 2 identical diploid daughter cells

Purpose: growth, tissue repair

Meiosis (sex cell division):

Two rounds of division (Meiosis I and II)

Result: 4 haploid gametes (sperm or eggs)

Crossing over in Prophase I creates genetic diversity

Independent assortment in Metaphase I

Spermatogenesis:

Spermatogonium → Primary spermatocyte → Secondary spermatocyte → Spermatids → Sperm

Produces 4 functional sperm per meiosis

Oogenesis:

Produces 1 egg (ovum) + 2–3 polar bodies (discarded)

Primary oocyte arrested in Prophase I from birth until puberty

Embryonic development:

Zygote → Cleavage (morula) → Blastula → Gastrulation (3 germ layers) → Neurulation

Ectoderm: skin, nervous system

Mesoderm: muscle, bone, cardiovascular

Endoderm: digestive, respiratory lining

Reference:

Wikipedia: Meiosis

https://en.wikipedia.org/wiki/Meiosis