The document summarizes the processes of conception, fertilization, implantation, fetal development and the development of organ systems in the fetus. It describes how the ovum and sperm are produced, how fertilization occurs when the sperm meets the ovum, and how the zygote then implants in the uterus. It outlines the stages of development from zygote to embryo to fetus. It also provides details on fetal membranes, the amniotic fluid, umbilical cord and placenta. Finally, it discusses the early development of major organ systems like the cardiovascular, nervous, endocrine, digestive and respiratory systems in the fetus.
12. Selected Examples of Single Gene Disorder DISORDER OCCURRENCES INHERITANCE DESCRIPTION ALBINISM 1:15,000-1:40,000 Autosomal Recessive Melanin lacking in skin, hair and eyes,nystagmus and photophobia CYSTIC FIBROSIS 1:2000-1:2500 Autosomal Recessive Abnormal exocrine gland function with pancreatic insufficiency , chronic pulmonary disease, excessive chloride in sweat DUCHENNE MUSCULAR DYSTROPHY 1:3000-1:5000 males X linked Recessive Progressive muscular weakness atrophy contractures, respiratory insufficiency and eventually death HEMOPHILIA A 1:2500-1:4000 males X linked Recessive Coagulation disorder due to deficiency of factor VIII HEMOPHILIA B 1:4000-1:7000 males X linked Recessive Coagulation disorder due to deficiency of factor IX POLYDACTYLY 1:100-1:300 X Linked Dominant Extra digits in hand s and feet
53. FETAL CIRCULATION STRUCTURE LOCATION FUNCTION Placenta Attached to the Uterus Gas exchange Umbilical Arteries Two Arteries in the Cord Carry UNO2 blood from the fetus to the placenta Umbilical Vein One Vein in the Cord Carry O2 blood to the fetus Foramen Ovale Opening in the inter-atrial septum Shunts blood from the right atrium to the left atrium so that blood can supplied the brain, heart and kidneys Ductus Venosus Accessory vein connecting umbilical vein into fetal liver and IVC To supply blood to liver. A bypass to the fetal liver Ductus Arteriosus Connection between fetal lungs and the aorta Shunts larger portion if the blood away from the lungs and directly to the aorta
54. FETAL CIRCULATION Blood from the Placenta Umbilical Vein Enter the Ductus Venosus Passes through the IFC Enter the Right Atrium Left Ventricle Aorta Right Atrium Enters the Right Ventricle Enters the Pulmonary Artery with some blood going to Lungs Flows to the Ductus Arteriosus Enters the Descending Aorta Enters the Hypogastric Artery goes back to Placenta