Organismal Development Part 3 Male Animals

Mitochondrion Intermembrane space Outer membrane Free ribosomes in the . Mitochondrion Intermembrane space Outer membrane Free ribosomes in the mitochondrial matrix Inner membrane Cristae Matrix Mitochondrial DNA 100 nm

Phermones

Earthworms are hermaphrodites

Protogynous (Male is blue)

External Fertilization

Internal Fertilization required

Spermatogenesis Epididymis Seminiferous tubule Testis Cross section of seminiferous tubule Spermatogonium Mitotic division, producing large numbers of spermatogonia Sertoli cell nucleus Differentiation and onset of meiosis I Primary spermatocyte (in prophase of meiosis I) Meiosis I completed Secondary spermatocyte Meiosis II Lumen of Seminiferous tubule Early spermatids Spermatids (at two stages of differentiation) Differentiation Sperm cells Neck Head Midpiece Tail Plasma membrane Acrosome Nucleus Mitochondria

Secondary Sexual Characteristics