Lecture Notes: Sexual Differentiation, Sex Determination, and Gametogenesis

1. Introduction

·       Sexual reproduction is the process by which two specialized reproductive cells—gametes (sperm and ovum)—fuse to form a zygote, leading to the formation of a new individual.

·       It promotes genetic variation, ensuring diversity and adaptability of the human species.

·       Sexual development in humans progresses through:

o   Chromosomal Sex Determination

o   Gonadal Differentiation

o   Phenotypic Sexual Differentiation

·       Gametogenesis (spermatogenesis and oogenesis) forms the functional male and female gametes.

Learning Objectives

·       Explain mechanisms of chromosomal sex determination.

·       Describe gonadal development and sexual differentiation pathways.

·       Discuss hormonal influences on internal and external genitalia development.

·       Outline the steps of spermatogenesis and oogenesis.