Sperm cells in the male reproductive tract are first created in the seminiferous tubules of the testes. From there they travel through the epididymis, vas deferens, ejaculatory duct, urethra, and penis. 

During spermatogenesis, one spermatogonia will become 4 separate functioning spermatozoa. In oogenesis, a primary oocyte will become 1 functioning ovum (or egg) while 3 polar bodies are also produced, which are nonfunctioning and never become eggs.

When a female ovulates, the oocyte is in metaphase II, until it becomes fertilized by a sperm. It then completes the second phase of meiosis to make a mature ovum. Remember that, unlike spermatogenesis, oogenesis begins during development. All oocytes undergo meiosis I during fetal development, and are kept suspended in prophase II until ovulation, when they shift to metaphase II. Meiosis only continues beyond metapahse II if fertilization occurs.

Spermatogenesis takes approximately 64 days in adult humans. Males begin producing sperm at puberty, and continue until death.

Oogenisis halts in the female embryo while the oocytes are trapped in meiosis II. At the beginning of the menstrual cycle a number of oocytes in primordial follicles are stimulated by pituitary gonadotropins to continue maturation.

Parthenogenesis is the activation and development of an egg without sperm. Parthenogensis, therefore, is not sexual reproduction, but can still result in a fully developed offspring.

Isogamy is a condition of indistinguishable male and female gametes, but they retain the ability to join in sexual reproduction. Hermaphroditism and pseudohermaphroditism are rare conditions in which a single organism produces both sperm and eggs and is able to self-fertilize in sexual reproduction.

The menstrual cycle has four phases: 

1) Menstrual phase (days 1-5): the uterus sheds its lining, which exits the body through the vagina in the form of menstrual fluid.

2) Follicular phase (days 1-13): the pituitary gland releases a hormone that stimulates the egg cells to grow. One egg cell matures in a sac-like follicle for 13 days; while it is maturing, the follicle releases a hormone that causes the uterus to develop its lining.

3) Ovulatory phase (day 14): the events listed in the question occur.

4) Luteal phase (days 15-28): the egg released during ovulation stays in the fallopian tube for 24 hours, disintegrating if not fertilized during that time. During this phase, the hormone that causes the uterus to retain its lining is used up, causing another menstrual phase to begin.

Hormone balance is extremely important in both developing the male and female fetus. Hormone levels can regulate and determine the relative level of sex characteristics that we see in individuals. Both sexes produces testosterone and estrogen, but utilize the hormones in different ways. Testosterone is produced at higher levels in males and is used to develop male secondary sex characteristics. Estrogen is produced at higher levels in females and is used to develop female secondary sex characteristics.

Progesterone is a secondary sex hormone that is also produced in both sexes. Females use progesterone to regulate the menstrual cycle, and levels of the hormone vary in women.

After fertilization occurs, the zygote undergoes a series of cellular divisions in a process called cleavage. This is followed by the formation of the blastula, a hollow sphere of cells. Gastrulation occurs next, where the embryo is divided into three germ layers: the endoderm, mesoderm, and ectoderm (from inside to outside). Hence, gastrulation is the stage in which this process first occurs. Neurulation and organogenesis occur after gastrulation.

Once a committed cell begins to develop specialized functions, it is known as differentiation. Before a cell differentiates, it makes a commitment to a certain cell type, first by specification, which is reversible, and then by determination, which is irreversible. Once a cell is committed to a cell type, it undergoes differentiation to develop specific cell characteristics.

Induction is a process in which cells induce adjacent cells to commit to a certain cell type.