1. 1 5 4 3 2 Placenta is the connection between mother and developing embryo Objective: Understand the Role of Placenta during Pregnancy Key words: Placenta, amnion, amniotic fluid, umbilical cord Fetus Placenta Umbilical Cord Amnion Amniotic Fluid

2. Objective: Understand the Role of Placenta during Pregnancy Key words: Placenta, amnion, amniotic fluid, umbilical cord

3.  Forms a barrier between mother and embryo (blood is not exchanged)  Delivers nutrients and oxygen  Removes waste from embryonic blood  Becomes an endocrine organ (produces hormones) and takes over for the corpus luteum  Estrogen  Progesterone  Other hormones that maintain pregnancy Objective: Understand the Role of Placenta during Pregnancy Key words: Placenta, amnion, amniotic fluid, umbilical cord

4. Fetus Placenta Umbilical Cord Cervix Amnion Amniotic Fluid Objective: Understand the Role of Placenta during Pregnancy Key words: Placenta, amnion, amniotic fluid, umbilical cord

5. 1. During the human development, membranes ______________ and nourish the embryo. 2. The amnion is a membrane that ______________ and protects the developing embryo within the uterus. 3. The placenta is the connection between _____________ and ________________. 4. The developing embryo needs a supply of ______________ and ___________________. 5. It also needs a means of eliminating _________________ and metabolic ____________. 6. Nutrient and oxygen in the blood of the __________________ diffuse into the blood of the __________________ through _____________________ 7. Wastes and carbon dioxide diffuse from the blood of the __________into the blood of the __________________through ________________________ 8. The ______________ is the embryo´s organ of respiration, nourishment, and excretion. 9. The _______________ allows the embryo to make use of the mother´s organ system while its own are developing. motherembryo nutrients oxygen carbon dioxide wastes mother embryoplacenta embryo motherplacenta protect nourish Objective: Understand the Role of Placenta during Pregnancy Key words: Placenta, amnion, amniotic fluid, umbilical cord

6. Objective: Understand What Factors Can Affect Fetal Development Key words: abnormalities, malnutrition, radiation, mutation, premature birth The Dangers that Face a Fetus It has often been said that there is no place as safe as a mother´s womb, or uterus. Surrounded by a watery cushion, kept warm and nourished, a fetus does have its safety provided by the mother. It is true that most infections that may make a mother ill cannot cross over the placenta and into the fetus. It is not true, however, that the fetus is entirely safe. Dangers can intrude into the small world of the fetus. Some forms of radiation can pass through the tissues of the mother and into the fetus. X rays, for example, can affect a fetus. The fetus is a place of tremendous cellular activity. Dividing cells are easily damaged by X rays. If the genetic material in one cell is altered, then every one of the millions of cells that develop from that damage single cell will contain the same defective genetic message. As a result of exposure to radiation, fetuses may have organs that do not work. Sometimes, the fetus cannot even survive. Some infectious microorganisms from the mother can enter the fetus. For example, different kinds of virus and bacteria can cause permanent brain damage, blindness, and even death of the fetus. Drugs taken in by the mother also can affect a developing fetus. Heroin, LSD, cocaine, and alcohol can endanger a fetus during pregnancy. Many serious effects result. Babies can be born addicted to these drugs. Mental retardation can occur due the alcohol that may pass from the mother´s blood into the fetus. When a pregnant woman smokes, it denies oxygen that its growing tissues need. Cigarettes smoke contains carbon monoxide, which replaces oxygen in the mother´s blood. Less oxygen in the mother´s blood means less oxygen for the fetus. A fetus that has suffered from the effects of cigarette smoking usually has a smaller birth weight, is more likely to die shortly after birth, or may have health problems for the rest of its life.

7. Factors that can affect fetal development How each factor affects fetal development Mutations Fetus’s organs may not work Permanent brain damage, blindness, or death Baby’s addiction to drugs Mental retardation Premature birth Lower birth weight Radiation – X rays Infectious microorganisms: virus & bacteria Drugs: Heroin, LSD, cocaine, alcohol Smoking Malnutrition Objective: Understand What Factors Can Affect Fetal Development Key words: abnormalities, malnutrition, radiation, mutation, premature birth

8. Objective: Understand What Factors Can Affect Fetal Development Key words: abnormalities, malnutrition, radiation, mutation, premature birth

9. 1) Do the data in the given tables justify scientists' conclusions that alcohol causes physical abnormalities at birth by interfering with the normal development of the fetus? Using one or more complete sentences, defend your position with supporting data. Yes. The babies whose mothers drank alcohol were smaller (2,555 g and 46.8 cm) than the babies whose mothers did not drink alcohol (3,094 g and 50.1 cm). Objective: Understand What Factors Can Affect Fetal Development Key words: abnormalities, malnutrition, radiation, mutation, premature birth

10. 2) What additional data would be needed to better support the scientists' conclusions? Scientists would need the number of premature babies Objective: Understand What Factors Can Affect Fetal Development Key words: abnormalities, malnutrition, radiation, mutation, premature birth Or the percentage of hearing impaired new born babies

11. 3) Using one or more complete sentences, explain why alcohol consumption by the mother is especially harmful during the early stages of pregnancy Alcohol is considered a poison, and it could interfere with cell division as the fetus is developing. Objective: Understand What Factors Can Affect Fetal Development Key words: abnormalities, malnutrition, radiation, mutation, premature birth

12. 4. Identify the structure labeled A and explain how the functioning of structure A is essential for the normal development of the fetus. [2] 5. Explain why consumption of alcoholic beverages by a pregnant woman is likely to be more harmful to her fetus than to herself. [1] Structure A: Women are advised to avoid consuming alcoholic beverages during pregnancy. The relative amount of alcohol is much greater in the fetus than in the mother due to the smaller size of the fetus. The fetus is still developing. Placenta Objective: Understand What Factors Can Affect Fetal Development Key words: abnormalities, malnutrition, radiation, mutation, premature birth Placenta delivers nutrients and oxygen to the embryo. It also removes waste from embryonic blood