Chapter Menu Lesson 1: Reproductive Systems Lesson 2: Development Before Birth Click on a hyperlink to view the corresponding lesson.

13.1 Reproductive Systems scrotum seminiferous tubule epididymis penis urethra vagina uterus fallopian tube follicle ovulation menstrual cycle

Male Reproductive System 13.1 Reproductive Systems Male Reproductive System The testes are inside a baglike structure called the scrotum. Cooler temperature in the scrotum enables sperm production.

Organs of Sperm Production 13.1 Reproductive Systems Organs of Sperm Production The testes contain tightly coiled tubes called seminiferous tubules where sperm are produced. The epididymis stores sperm and connects to the vas deferens.

Organs of Sperm Transfer 13.1 Reproductive Systems Organs of Sperm Transfer The penis transfers sperm to a female’s reproductive parts. The urethra extends to the end of the penis and carries sperm out of the body.

13.1 Reproductive Systems Sperm Production Males start producing sperm during puberty, which usually begins at 10–16 years of age. A male can continue to make healthy sperm for the rest of his life.

Sperm and Semen Each sperm contains a: head midpiece tail (flagellum) 13.1 Reproductive Systems Sperm and Semen Each sperm contains a: head midpiece tail (flagellum) Semen contains mucus, ascorbic acid, hormonelike substances, an enzyme, and sugar.

Female Reproductive System 13.1 Reproductive Systems Female Reproductive System A female’s reproductive system produces eggs before she is born. This system is also where a fertilized egg can grow and develop into a baby.

Female Reproductive Organs 13.1 Reproductive Systems Female Reproductive Organs All the reproductive organs of a female are located inside her abdomen. Sperm are deposited in the vagina.

13.1 Reproductive Systems Uterus The uterus is a thick, muscular organ inside which a fertilized egg can develop. The cervix is the opening of the uterus into the vagina.

Ovaries and Fallopian Tubes 13.1 Reproductive Systems Ovaries and Fallopian Tubes A pair of organs called ovaries produces eggs. An egg released from an ovary moves into the fallopian tube— oviduct—that connects to the uterus.

Ovaries and Fallopian Tubes (cont.) 13.1 Reproductive Systems Ovaries and Fallopian Tubes (cont.) Fertilization usually occurs while the egg is in a fallopian tube.

13.1 Reproductive Systems Egg Production Human eggs are produced through meiosis beginning before a female is born. The primary oocytes remain unchanged until a female begins puberty at 9–13 years of age.

13.1 Reproductive Systems Egg Production (cont.) A follicle is an egg cell and its surrounding cells. Ovulation is the release of an egg from a follicle into a fallopian tube.

13.1 Reproductive Systems Menstrual Cycle The menstrual cycle are the changes that take place before, during, and after ovulation.

13.1 Reproductive Systems Menstrual Flow If a released egg is not fertilized, the endometrium breaks down. The tissue, some blood, and the unfertilized egg leave the vagina as menstrual flow.

13.1 Reproductive Systems Ovulation Ovulation occurs about two weeks after the first day of menstrual flow. If the egg is fertilized, a zygote forms, cell divisions begin, and an embryo begins to develop.

13.1 Reproductive Systems Hormones Chemical messengers called hormones regulate the timing of the menstrual cycle and ovulation.

Menopause Most women enter menopause between the ages of 46 and 54. 13.1 Reproductive Systems Menopause Most women enter menopause between the ages of 46 and 54. They stop ovulating and no longer have menstrual cycles.

13.1 Reproductive Systems Fertilization For a sperm to fuse with an egg cell, the sperm must swim to the fallopian tube near the time of ovulation. Sperm can live for up to three days inside female reproductive tract.

13.1 Reproductive Systems Fertilization (cont.)

Where are sperm stored? A testis B vas deferens C epididymis D urethra 13.1 Reproductive Systems Where are sperm stored? A testis B vas deferens C epididymis D urethra A B C D Lesson 1 Review

How long does a menstrual cycle last? A 7 days B 16 days C 28 days 13.1 Reproductive Systems How long does a menstrual cycle last? A 7 days B 16 days C 28 days D 36 days A B C D Lesson 1 Review

Where does fertilization of eggs occur? A vagina B ovary C uterus 13.1 Reproductive Systems Where does fertilization of eggs occur? A vagina B ovary C uterus D fallopian tube A B C D Lesson 1 Review

End of Lesson 1

13.2 Development Before Birth pregnancy trimester fetus prenatal care placenta umbilical cord

13.2 Development Before Birth Fetal Development Cell divisions of a human zygote begin about 24 hours after fertilization.

Growth and Development of Body Systems 13.2 Development Before Birth Growth and Development of Body Systems Pregnancy is the development of a baby within a female’s uterus. Usually lasts 38 weeks after fertilization, or about 40 weeks after the beginning of the last menstrual cycle Nine months of pregnancy divided into trimesters Fertilization and Birth

13.2 Development Before Birth Stages of Pregnancy

13.2 Development Before Birth Premature Babies Some of their organs, including lungs, are not ready to function Can have physical and behavioral problems as they grow older What are the stages of development before birth?

Placenta and Umbilical Cord 13.2 Development Before Birth Placenta and Umbilical Cord The exchange of materials between a pregnant woman and her fetus takes place through a placenta. Substances enter and leave the body of a fetus through an umbilical cord.

Placenta and Umbilical Cord (cont.) 13.2 Development Before Birth Placenta and Umbilical Cord (cont.)

13.2 Development Before Birth Prenatal Care Everything that happens in a woman’s body has an effect on her developing fetus. Prenatal care is the health care designed to protect the health of a pregnant woman and prevent problems in her developing fetus.

13.2 Development Before Birth Nutrition The energy and nutrients a fetus needs must come from its mother. A pregnant woman is usually advised to add about 300 extra calories a day to her diet. Without a certain amount of folic acid, spinal cord formation is abnormal. A pregnant woman should avoid caffeine or consume very little.

Environmental Factors 13.2 Development Before Birth Environmental Factors Harmful substances can be consumed in food, and absorbed through the skin. A pregnant woman is advised to avoid substances that could harm her or her fetus. Lead is especially dangerous to a fetus, infant, or young child.

13.2 Development Before Birth Viruses Viruses can pass from a pregnant woman to her fetus through the placenta or during childbirth. Some viruses do not cause harm to adults, but can be very harmful to a fetus or a newborn. Some examples are: Chicken pox Genital herpes

13.2 Development Before Birth Drugs and Alcohol A medicine that is safe for an adult might not be safe for a developing fetus. Nicotine has serious negative effects on a fetus. The use of alcohol excessively risks having a baby with fetal alcohol syndrome (FAS). Illegal drugs increase the chances for miscarriage, premature birth, low birth weight, and behavioral problems.

13.2 Development Before Birth When does an embryo develop the structures that will become the major organ systems? A fertilization B first trimester C second trimester D third trimester A B C D Lesson 2 Review

How do substances enter and leave a fetus? A through the uterus 13.2 Development Before Birth A B C D How do substances enter and leave a fetus? A through the uterus B through the endometrium C through an umbilical cord D through the mouth Lesson 2 Review

Which of the following would not describe good prenatal care? 13.2 Development Before Birth A B C D Which of the following would not describe good prenatal care? A eating healthy foods B taking vitamin supplements C avoiding pesticides D taking over-the-counter medications without doctor approval Lesson 2 Review

End of Lesson 2

Chapter Resources Menu Chapter Assessment California Standards Practice Concepts in Motion Image Bank Science Online Interactive Table Virtual Lab BrainPOP Click on a hyperlink to view the corresponding feature.

Where are sperm produced? A vas deferens B epididymis C seminiferous tubules D urethra Chapter Assessment 1

When do females begin producing eggs? A before birth B puberty C at the beginning of their menstrual cycle D ovulation Chapter Assessment 2

A B C D What is the term for cells undergoing meiosis that stop during metaphase II? A egg B primary oocyte C secondary oocyte D follicle Chapter Assessment 3

How long can sperm live inside a female’s reproductive system? B C D How long can sperm live inside a female’s reproductive system? A 12 hours B 24 hours C 48 hours D 72 hours Chapter Assessment 4

On average, how many more calories per day does a pregnant woman need? B C D On average, how many more calories per day does a pregnant woman need? A 0 B 300 C 1,000 D 2,000 Chapter Assessment 5

When do males start producing sperm? A before birth B birth C puberty SCI 5.d A B C D When do males start producing sperm? A before birth B birth C puberty D around age 5 CA Standards Practice 1

Where does a fertilized egg develop? A ovary B uterus C stomach SCI 5.d A B C D Where does a fertilized egg develop? A ovary B uterus C stomach D fallopian tube CA Standards Practice 2

Which organs produce eggs? A ovaries B testis C fallopian tubes SCI 5.d A B C D Which organs produce eggs? A ovaries B testis C fallopian tubes D uterus CA Standards Practice 3

What structure moves sperm through a female’s reproductive system? SCI 5.d A B C D What structure moves sperm through a female’s reproductive system? A muscle B cilia C fallopian tube D flagellum CA Standards Practice 4

Which is not exchanged between mother and fetus in the placenta? SCI 5.d A B C D Which is not exchanged between mother and fetus in the placenta? A nutrients B blood C fetal wastes D medicines CA Standards Practice 5

Concepts in Motion 1

Image Bank

Interactive Table

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