1. Human Development
REPRODUCTION:
Reproductive Systems
Fertilization
Pregnancy
Child Birth

2. The Human Reproductive System
Reproduction is the process by which living organisms produce others of their own kind.
Human life results from the union of two cells: one from the male and one from the female.
These cells are produced by structures in the male and female reproductive systems and merge in the female during sexual intercourse
The human reproductive system consists of body organs and structures that make it possible to produce young.

3. The Male Reproductive System
The function of the male reproductive system is to produce sperm and transmit them to the female reproductive system.
Sperm are the male reproductive cells. They are first produced during puberty which begins in boys between

4. The Male Reproductive System
In males, the process of reproduction begins in the testes. The testes are the pair of glands that produce sperm and testosterone. Testosterone is the hormone that regulates male sexual development. When a male is sexually stimulated, sperm leaves the testes through tubes that lead to the urethra.
Along the way, the sperm mix with fluids that protect them and help them to travel. The mixture of sperm and fluids is called semen. Semen is released from the urethra through the penis. The muscular action that forces the semen through the urethra and out of the penis is called ejaculation.

5. The Female Reproductive System
The female reproductive system has four main functions:
It produces the hormones estrogen and progesterone
It stores and releases female reproductive cells, called eggs or ova
It allows fertilization to take place.
It nourishes and protects the developing child until it is able to survive outside the female’s body.

6. Parts of the Female Reproductive System
At puberty the ovaries, the two female reproductive glands, start to release eggs, or ova. The ovaries also increase production of estrogen and progesterone, hormones that are necessary for female sexual development.
The two fallopian tubes lead from the ovaries to the uterus. An egg travels from an ovary to the uterus by way of a fallopian tube. Fertilization takes place in a fallopian tube.
A fertilized egg becomes implanted in the uterus, a pear-shaped organ in which a developing child is nourished. The uterus is also called a womb.
The cervix is the opening at the bottom of the uterus.
Labia are folds of skin that cover the opening of the vagina.
The vagina is the muscular passageway that leads from the uterus to the outside of the body. Menstrual flow leaves the body through the vagina. In addition, a baby is pushed out of its mother’s body through the vagina.

7. Ovulation (the releasing of an egg from the ovaries)
The Menstrual Cycle
Ovulation (the releasing of an egg from the ovaries)
may start as soon as a girl reaches puberty. Generally, this is between the ages of 8-12 although some girls can ovulate for the first time, also known as menarche, as early as 8 or as late as After Ovulation,
If fertilization occurs, the lining of the Uterus, also known as the Endometrium, will develop further and nourish the fertilized egg.
If fertilization does not occur, which is what usually happens, the Uterine lining and un-used egg dissolve and mix with a small amount of blood. The body sheds the lining through the vagina. This is known as menstruation
For most girls, menstruation starts between ages 8 and 16. When a female is pregnant, the lining is not shed, so she does not menstruate.

8. The Menstrual Cycle (cont’d.)
Menstrual flow stops after about 5 days.
Ovulation: A mature egg is released from the ovary into a fallopian tube.
If fertilization has not occurred, the uterine lining begins to break down.
Menstrual flow begins.
Fertilization is most likely to occur during these days.
Menstruation usually occurs approximately every 28 days. A menstrual period lasts for about 5 days. However, the length of both the menstrual cycle and the period can vary from female to female. A teen girl’s menstrual cycle may change from month to month. This should not be a cause for concern unless menstruation stops for months at a time.

10. Sexual Intercourse: Act of Reproduction
The act of reproduction in humans is when the male inserts their penis into the women’s vagina. Upon climax, “semen” is ejaculated into the women. The Semen contains 4 things: Fluid from 3 different organs in the male reproductive system and the Sperm produced in the Testicles.

12. Fertilization
Sperm entering the vagina travel through the uterus to the fallopian tubes. Fertilization takes place in a fallopian tube when a male sperm cell and a female egg cell unite.

15. Fertilization
The fertilized egg then moves through the fallopian tube to the uterus, where it becomes implanted.
In the uterus, the fertilized egg gradually grows and develops.

16. Fertilization and implantation on the Uterus Wall

17. Now we’re pregnant!
At the moment the fertilized egg also known as a blastocyst, implants into the uterus, the women is officially, not just technically pregnant.
Common Signs of pregnancy include:
-missed “period” or abnormally short/light “period”
-breast tenderness or fullness
-nausea or vomiting
-changes in appetite including cravings
-frequent urination
-un-explained fatigue
-Gas

18. Decisions Decisions Decisions
Once a girl/woman finds out she is pregnant..she is faced with a major decision with 3 possible outcomes:
Have the baby ) alone or 2) with partner?
Place baby up for adoption 1) closed secret adoption
2) Open mother selected adoption
(* note: in some states, babys can be placed into temporary foster care instead of adoption until the mother “gets on her feet”)
3) Abortion In the US most abortions are performed during the first 14 weeks.. It is considered illegal to have an abortion in most states after 14 weeks unless it involves health complications to the mother or fetus.
For the purposes of this lesson, you are not getting an abortion..so what happens next?

19. Development After Fertilization
The human body begins as a single fertilized cell known as a blastocyst. The fertilized cell starts to divide into a number of cells and is called a zygote. Then, it implants itself into the uterus lining and begins to build structures of the body. It is then referred to as an embryo.
After the eighth week, the embryo is called a fetus and looks like a baby (for the most part) but is very tiny.
From the moment of fertilization until birth, the cells develop into tissues, organs, and body systems.
The fertilized cell is a result of the union of a sperm and an egg. The fertilized cell then starts to divide—over a period of hours, one cell becomes two, two cells become four, four become eight, and so on. From the moment of fertilization until birth, the cells develop into tissues, organs, and body systems.

20. Fertilization/implantation including cell division

21. The Developing Fetus 6 Months Fertilization 9 Months 3 Months
Length: 12 ½ inches
Weight: 1 ½ pounds
Behavior: kicks, hears sounds
Fertilization
The union of the sperm cell with an egg cell forms an embryo
Pregnancy generally lasts a little over nine months. From the start, the developing fetus receives nutrients and oxygen from its mother through a tube called the umbilical cord, which is attached to its abdomen. The stages of the developing fetus are as follows:
Fertilization
A sperm cell unites with an egg cell. This union forms an embryo that is microscopic in
size.
3 Months
Length: 3 inches
Weight: 1 ounce
New Features: arms, legs, fingers, toes, brain, nerves; heartbeat can be heard using a
special instrument.
Behavior: begins to move
6 Months
Length: 12½ inches
Weight: 1½ pounds
New Features: eyebrows, fingernails
Behavior: kicks, hears sounds
9 Months
Length: 18–20 inches
Weight: 7–9 pounds
New Features: smooth skin
Behavior: eyes open, fingers can grasp, body organs and systems can work on their own.
9 Months
Length: 18–20 inches
Weight: 7–9 pounds
Behavior: eyes open, fingers can grasp, body organs and systems can work on their own
3 Months
Length: 3 inches
Weight: 1 ounce
Behavior: begins to move

22. Full term pregnancy orientations of the baby

23. Full term pregnancy orientations of the baby
A baby should only be delivered vaginally (regular traditional birth) if the baby’s head is pointing down and the crown of the baby’s head is against the cervix. If the baby is “breech” a Cesarean Section is normally performed to removed the baby from the mother by cutting her in the bikini or waste area and cutting through her lower abdominal muscles and uterus. The baby is then gently lifted out.

24. OTHER STUFF TO KNOW AND CONSIDER?

25. Length of pregnancy?
Most people say “9 months” but in reality, it’s 10. A pregnancy lasts 40 weeks.
Pregnancies are divided into 3 trimesters of about 13 weeks each (give or take)
Click to show the correct answer.

26. Care During Pregnancy DO: DON’T: Eat healthful foods.
Have regular checkups.
Beware of infections.
DON’T:
Smoke or use tobacco.
Drink alcohol.
Take any unnecessary drugs.

27. Heredity
Certain traits are traits you have inherited from your parents.
Structures within cells influence heredity.
Chromosomes are threadlike structures that carry the codes for inherited traits.
Each chromosome is divided into thousands of small parts called genes
Children inherit genes for each trait from each parent.
Traits such as height, facial features, and the color of the skin, hair, and eyes are traits that children inherit from their parents. Chromosomes carry codes for inherited traits. Almost all human cells contain 46 chromosomes in 23 pairs.
The genes that children inherit from their parents interact in complex ways, resulting in a particular set of inherited characteristics.

28. Heredity (cont’d.) Egg cell Embryo Sperm cell 23 chromosomes
Unlike other body cells, sperm and egg cells do not have 46 chromosomes. Each has 23 chromosomes.
When the sperm cell and the egg cell unite during fertilization, they produce an embryo that contains 46 chromosomes. The chromosomes in the sperm determine whether the child will be a boy or a girl. Each egg cell contains one X (female) chromosome. Each sperm cell contains either an X (female) or a Y (male) chromosome.
An XX chromosome combination will produce a female child.
An XY chromosome will produce a male child.
46 chromosomes
23 chromosomes

29. Sex = Gender
22 of the 23 pairs of chromosomes are numbered. The 22nd is lettered either XX or XY.
Recall that ½ of your chromosomes come from your mom and ½ from your dad.
Eggs are always X and Sperm can be either X or Y.
IF an X sperm fertilizes an egg, it will be a girl.
If a Y sperm fertilizes an Egg, it will USUALLY, be a boy
XY = boy XX = Girl
Click to show the correct answer.

30. Sex = Gender
However, if a Y chromosome fertilizes and egg, during the 1st trimester, a chemical is secreted that must travel around the developing embryo and reach the gonads (reproductive organs BEFORE they actually become reproductive organs)
If the chemical reaches the gonads, the embryo will grow the parts of the male reproductive system. If the chemical does not reach the gonads, the developing embryo will become a girl
Click to show the correct answer.

31. Genetic problems at birth?
Genetic problems can cause serious disorders. Down syndrome, for example, is a genetic disorder in which a person’s cells have 47 chromosomes instead of 46.
Such disorders can affect physical or mental development, or both.
Genetic disorders may be mild or severe; a few are fatal.

32. Care During Pregnancy Again….it is EXTREMELY IMPORTANT to
eat healthy and avoid drugs and get regular check ups while pregnant!!!
Your baby’s entire future can be effected by what you do!