MCB 135E Physiology of Development GSI: Jason Lowry Discussion Week 9/6-9/10

General Information 1.Discussions: a.Thursday – in 130 Wheeler b.Friday – 2-3 in 219 Dwinelle 2.Office Hours: a.Thursday – 1-2 in 208 Donner 3.

Introduction Terminology –Physiology –Development –Growth Concepts –Divisions of Life-Span –Periods of Development

Terminology Physiology –Study of Function Development –Functional Changes with Age –Fertilization  Death –Follows a predictable timetable Growth –Change in Size –Index used to measure development

Concepts Divisions of Life-Span (Intro. Table 1) –Pre-Natal –Post-Natal Life Periods of Development (Intro. Table 2) –Starts with fertilization and proceeds in a continuous and orderly sequence throughout the pre-natal and post-natal periods

Gametogenesis and Fertilization Male Reproductive System –Anatomy –Gametogenesis –Endocrinology Female Reproductive System –Anatomy –Gametogenesis –Endocrinology Fertilization –Terminology –Roles of Gametes –Stages of Development

Gametogenesis Terminology –Gamete – Either the Mature Sperm or Ovum –Zygote – Formed by the union of the mature Sperm with mature Ovum –Gametogenesis – Development of Male (Spermatogenesis) and Female (Oogenesis) sex cells

Spermatogenesis Formation of Spermatozoa (Sperm) Occurs in seminiferous tubules Involves two distinct maturational processes –Spermatocytogenesis 1 st Stage of sperm formation Spermatogonium  Spermatids Involves mitosis initially and then meiosis –Spermiogenesis Spermatids  Spermatozoa

Male Reproductive Endocrinology

Oogenesis

Gamete Comparison Male –Sperm –Small Size –Elongated Shape –Millions in # –Vigorous Motility –No protecting envelope –Minimal Cytoplasm –Lacks yolk –Centrosome Retained –Mitochondria in body –Golgi Apparatus in acrosome –Nucleus condensed in head –XY Female –Ovum –Large size –Spheroidal shape –Few in # –Lack motility –Egg envelopes for protection –Bulky Cytoplasm –Little Yolk –Centrosome Disappears –Diffuse mitochondria –Diffuse golgi apparatus –Open structured nucleus –XX

Reproductive Endocrinology Male –Hypothalamus GnRH –Anterior Pituitary FSH/LH –Testes Testosterone Inhibin Female –Hypothalamus GnRH –Anterior Pituitary LH/FSH –Ovaries E P Inhibin

Fertilization Terminology –Fertilization the formation, maturation, and union of the Ovum and Sperm Roles of Ovum –Contribute the maternal complement of genes –Reject all sperms but one –Provide food reserve until the embryo begins to feed upon exogenous material Roles of Sperm –Reach and penetrate the egg –Activate the egg to nuclear and cytoplasmic division necessary to embryonic development –Contribute the paternal complement of genes