SC.912.L16.13 Describe the basic anatomy and physiology of the human reproductive system. Describe the process of human development from fertilization to birth and major changes that occur in each trimester of pregnancy. The Reproductive System

The Male Reproductive System The main function is to produce sperm, or male sex cells and to deliver these cells to the ovary of the female for fertilization. Anatomical path of sperm from formation to ejaculation Testes, Epididymis, Vas deferens, Prostate, and Urethra

Structure of a Sperm

The Female Reproductive System Function: 1. Produces and nourishes the egg cells that carry the female’s genetic information. 2. It nourishes and protects the developing offspring if an egg is fertilized.

Fertilization Fertilization is the joining of a sperm and egg cell. A zygote is a fertilized egg results from the fusion of the nuclei of two gametes (egg and sperm)

Prenatal development (Embryonic and Fetal) Zygote, Morula, Blastocyst, Grastula, Fetus Structure made of cells that forms early in mammalian pregnancy. The inner cell mass creates the tissues of the body, while the outer cell mass creates the placenta

Gastrulation and Neurulation Gastrulation produces the three cell layers of the embryo. Ectoderm, mesoderm and endoderm. Neurulation which is the first step in the development of the nervous system

First Trimester The zygote divides several times to form a hallow ball called a blastula The blastula implants in the walls of the uterus. Cells continue dividing and form the gastrula. The placenta starts to secrete HCG (human chorionic gonadotropin) so the embryo stays attached to the uterus The major body structures develop in their basic form during the first trimester.

Spina bifida is part of a group of birth defects called neural tube defects. The neural tube is the embryonic structure that eventually develops into the baby's brain and spinal cord and the tissues that enclose them. Normally, the neural tube forms early in the pregnancy and closes by the 28th day after conception. In babies with spina bifida, a portion of the neural tube fails to develop or close properly, causing defects in the spinal cord and in the bones of the backbone. Folic acid (Folate/Vitamin B9) can prevent this condition

Second trimester Grows larger and develops all structures it needs to survive at birth. Fetus starts to move Forms lanugo hair on its body Sucks its thumb, swallows, hiccups The fetus has fully developed eyes and the lungs start to develop

Third Trimester The brain develops rapidly. The fetus doubles its mass The fetus has regular breathing motions The central nervous systems and lungs complete their development