Reproduction & Heredity “In a previous lesson, we focused mainly on the anatomy of the reproductive systems. Let’s test your memory.” HAVE STUDENTS PARTICIPATE IN THE JOURNEY OF SPERM AND EGG ACTIVITY. (Teachers, you will need to have made the signs ahead of time.) “Today, we will look at pregnancy and possible complications that might come with it.” 6/1/2018 TEKS: HE.3A, HE.3B, HE.3D

Heredity Chromosomes: Tiny threadlike structures that carry hereditary information from generation to generation. Every cell contains 46 chromosomes, 23 from each genetic parent. “Chromosomes are tiny threadlike structures that carry hereditary information from generation to generation. This is how traits are passed down. Every cell contains 46 chromosomes, 23 from each genetic parent.” 6/1/2018

Chromosomes Kinds of Chromosomes X Chromosomes Y Chromosomes Combinations XX - Vagina XY - Penis Genetic Mother Genetic Father There are 2 kinds of chromosomes, X and Y. Everyone gets chromosomes from both of their genetic parents. Many people either have 2 X chromosomes or one X and one Y chromosome. People with XX chromosomes usually have a vagina and often identify as female. People with XY chromosomes usually have a penis and often identify as male. Vagina Penis 6/1/2018

Chromosomes Sometimes a person gets more than one Chromosome from each genetic parent. Other combinations: XXY - Penis XYY – Penis XXX - Vagina Sometimes people have more chromosomes than just XX or XY. People with these combinations of chromosomes have 47 instead of 46 chromosomes. Most of the time people with these other combination of chromosomes develop the same as people with XX or XY chromosomes. Sometimes they may be taller or shorter, have delayed language development or a lower IQ. Sometimes people with these other combinations don’t have any observable differences. 6/1/2018

Genes: Chromosomes are divided into smaller units which contain instructions to help determine a certain characteristic of an individual. DNA: makes up the genes “Chromosomes are divided into smaller units which contain instructions to help determine certain characteristics of an individual. DNA makes up the genes.” 6/1/2018

Dominant Genes: A person will show the trait coded for by the gene even if only one gene is present Recessive Genes: Trait occurs only if a dominant gene is not present. (ex: red hair) “For dominant genes, a person will show the trait coded for by the gene even if only one gene is present. What is a recessive gene? It occurs only if a dominant gene is not present. If blond hair runs in the family and you randomly have red hair, you have inherited a recessive gene. There is a 1-in-4 chance of that happening.” 6/1/2018

Stages of Reproduction Fertilization: Joining of an egg and a sperm in the fallopian tube “Joining of an egg and a sperm in the fallopian tube.” 6/1/2018

embryo is called a fetus. A fertilized egg in the first 2 months “A fertilized egg in the first two months is called an embryo. What is a fetus? From the 3rd month on, the embryo is called a fetus.” Fetus: From the 3rd month on, the embryo is called a fetus. 6/1/2018

Describe fetal development milestones. 6/1/2018

Importance of Prenatal Care: Prenatal care can help prevent complications during pregnancy and ensure the infant's health and development. Some important steps pregnant women can take to help reduce the risk for problems are: Follow a healthy, safe diet. Get regular exercise. Avoid exposure to potentially harmful substances such as lead and radiation. Control existing conditions, such as high blood pressure and diabetes. Avoid tobacco smoke and alcohol use. Discuss the importance of prenatal care to help prevent complication during pregnancy. 6/1/2018

Stages of Childbirth: Labor – Mild contractions push the fetus against the cervix. 2. Birth – fetus pushes through the cervix and into the birth canal. 3. After birth – After the infant is delivered, the placenta separates from the uterus and is delivered. “The first stage is called Labor. Labor is when there are mild contractions that push the fetus against the cervix. The second stage is called Birth. Birth is when the fetus pushes through the cervix and into the birth canal. The third stage is called the after birth. After birth is when, after the infant is delivered, the placenta separates from the uterus and is delivered. A contraction is the uterus contracting, not the fetus kicking. Water breaking is the placenta sac breaks and amniotic fluid is released. This creates an unsterile environment for the fetus, so the fetus needs to be born quickly. After the umbilical cord is cut, the placenta is still in the uterus. The placenta is pushed out after the infant is delivered. (afterbirth).” 6/1/2018

Diagram of the stages of birth. 6/1/2018

Types of Birth Now we’re going to talk about different kinds of birth. 6/1/2018

Fetus comes out of the vagina. Vaginal Birth: Fetus comes out of the vagina. “Vaginal birth is when the fetus comes out of the vagina” 6/1/2018

Feet or butt of a fetus enters the birth canal first Breech Birth: Feet or butt of a fetus enters the birth canal first “Feet or butt of fetus enter the birth canal first.” 6/1/2018

Cesarean Section (C section): An incision is made in the abdomen and uterus in order to deliver the fetus. “Cesarean sections are also known as a “C” section. An incision is made in the abdomen and uterus in order to deliver the fetus. C-sections are done for a number of reasons – usually any medical issue putting the health of the fetus or the mother in jeopardy. A person can sometimes be have a vaginal birth if they become pregnant again after a C-section. It’s important to talk about the risks involved of having a vaginal birth after a C-section with a health care provider. 6/1/2018

Multiple births 6/1/2018

Identical (Monozygotic) Twins: Embryos that develop from the same fertilized egg that split into two “Identical twins are twins developed from the same fertilized egg that splits into two eggs. This means that one egg was fertilized by one sperm and divided into two different embryos. Twins are genetically predisposed sometimes. Fertility drugs increase the likelihood of having twins.” 6/1/2018

Fraternal (Dizygotic) Twins: Embryos that develop at same time but from separate fertilized eggs “Fraternal twins are twins that develop at same time but from separate fertilized eggs. This means an ovary released 2 separate eggs and they were fertilized by 2 different sperm.” 6/1/2018

Use the diagram provided to explain monozygotic Use the diagram provided to explain monozygotic. “Monozygotic is the term relating to twins and multiple births.” Explain that this occurs when the same fertilized egg splits. 6/1/2018

Prenatal Diagnosis: Amniocentesis: Test performed by taking amniotic fluid from the pregnant person Ultrasound: Sound waves used to produce images of the fetus “Amniocentesis is a test performed by taking amniotic fluid from the pregnant person. An ultrasound is sound waves used to produce images of the fetus.” 6/1/2018

Possible problems associated with pregnancy 6/1/2018

The fetus needs iron to make red blood cells. Anemia: A low number of healthy red blood cells and insufficient iron in the pregnant person. The fetus needs iron to make red blood cells. “Anemia is a low number of healthy red blood cells and insufficient iron in the mother. The fetus needs iron to make red blood cells.” List symptoms associated with anemia. “Pregnant people who are anemic can give birth to unhealthy babies because of a lack of red blood cells.” Discuss the importance of iron and prenatal vitamins in pregnant people. 6/1/2018

The body retains toxic waste, which Toxemia: The body retains toxic waste, which can lead to high blood pressure, swollen feet, hands, and face. If left untreated, it can lead to convulsions and coma. “The body retains toxic waste, which can lead to high blood pressure, swollen feet, hands and face. If left untreated, it can lead to convulsions and coma.” 6/1/2018

Gestational Diabetes: Occasionally a pregnant person may temporarily develop diabetes, usually near the end of their pregnancy, which can cause the baby to be bigger than they might have been. “A pregnant person may temporarily develop diabetes, usually near the end of her pregnancy. Gestational diabetes can cause the fetus to get very big.” 6/1/2018

Miscarriage: Fetal death before 20 weeks of pregnancy. Still Birth: Fetal death after 20 weeks of pregnancy. “Miscarriage is the spontaneous loss of a pregnancy before the 20th week. Muscles in the uterus contract and force a nonliving embryo/fetus from the body. About 15 to 20% of known pregnancies end in miscarriage. But the actual number is probably much higher because many miscarriages occur so early in pregnancy that a person doesn't even know they are pregnant. Most miscarriages occur because the fetus isn't developing normally. Miscarriage is a relatively common experience — but that doesn't make it any easier. What is still birth? Still birth is the birth of an infant that has died in the womb after having survived through at least the first 20 weeks of pregnancy. Still Birth occurs in 1 out of 200 pregnancies. The reason behind 50% of stillbirth cases is unknown.” 6/1/2018

Physical or mental disabilities that are present at birth Birth Defects: Physical or mental disabilities that are present at birth Fetal Alcohol Spectrum Disorder: Birth defects caused by alcohol consumption during pregnancy *This disability is 100% preventable! “Birth defects are physical or mental disabilities that are present at birth. What is Fetal Alcohol Spectrum Disorder? FASD are birth defects caused by alcohol consumption during pregnancy. This is 100% preventable.” 6/1/2018

Incubator: Keeps a premature infant in a sterile environment and at a warm temperature until they are fully developed Premature Birth: Infant born before they are fully developed (before 37 weeks) “Incubators keep premature infants in a sterile environment and at a warm temperature until they are fully developed. What is premature? Premature is referring to infants who are born before they are fully developed (before 37 weeks). 1 out of every 9 babies is born premature in the U.S.” 6/1/2018

prenatal testing NECESSARY? IS prenatal testing NECESSARY? Why or why not? Discuss 6/1/2018