female reproductive system

organs of the female reproductive system

The female reproductive organs include the ovaries, fallopian tubes, uterus, and vagina. These organs are shown in Figure 22.3, along with some other structures of the female reproductive system. Find each organ in the drawing as you read about it below. For a cartoon about the female reproductive system, watch this video: http://education-por The two ovaries are small, oval organs on either side of the abdomen. Each ovary contains thousands of eggs. However, the eggs do not develop fully until a female has gone through puberty. Then, about once a month, an egg is released by one of the ovaries. The ovaries also secrete estrogen. The two fallopian tubes are thin tubes that are connected to the uterus and extend almost to the ovaries. The upper end of each fallopian tube has fingers (called fimbriae) that sweep an egg into the fallopian tube when it is released by the ovary. The egg then passes through the fallopian tube to the uterus. If an egg is fertilized, this occurs in the fallopian tube. The uterus is a hollow organ with muscular walls. The uterus is where a baby develops until birth. The walls of the uterus stretch to accommodate the growing fetus. The muscles in the walls contract to push the baby out during birth. The uterus is connected to the vagina by a small opening called the cervix. The vagina is a cylinder-shaped organ that opens to the outside of the body. The other end joins with the uterus. Sperm deposited in the vagina swim up through the cervix, into the uterus, and from there into a

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functions of the female reproductive system

Two functions of the female reproductive system are similar to the functions of the male reproductive system: producing gametes and secreting a major sex hormone. In the case of females, however, the gametes are eggs, and they are produced by the ovaries. The hormone is estrogen, which is the main sex hormone in females. Estrogen has two major roles: During adolescence, estrogen causes the changes of puberty. It causes the reproductive organs to mature. It also causes other female traits to develop. For example, it causes the breasts to grow and the hips to widen. During adulthood, estrogen is needed for a woman to release eggs from the ovaries. The female reproductive system has another important function, which is not found in males. It supports a baby as it develops before birth. It also gives birth to the baby at the end of pregnancy.

structure and function of eggs

Human eggs are very large cells. In fact, they are the largest of all human cells. You can even see an egg without a microscope. Its almost as big as the period at the end of this sentence. Like a sperm cell, an egg cell is a haploid cell with half the number of chromosomes of other cells in the body. Unlike a sperm cell, the egg lacks a tail and contains a lot of cytoplasm.

producing eggs

When a baby girl is born, her ovaries contain all of the eggs they will ever produce. But these eggs are not fully developed. They develop only after the female reaches puberty at about age 12 or 13. Then, just one egg develops each month until she reaches her 40s or early 50s.

menstrual cycle

Egg production in the ovary is part of the menstrual cycle. The menstrual cycle is a series of changes in the reproductive system of mature females that repeats every month on average. These changes include the development of an egg and follicle in the ovary. While the egg is developing, other changes are taking place in the uterus. It develops a thick lining that is full of tiny blood vessels. The lining prepares the uterus to receive a fertilized egg if fertilization actually takes place. If fertilization doesnt occur, the egg passes through the uterus and vagina and out of the body. The lining of the uterus also breaks down. Blood and other tissues from the lining pass through the vagina and leave the body. This is called menstruation. Menstruation is also called a menstrual period. It typically lasts about 4 days. When the menstrual period ends, the cycle begins repeats.

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how eggs form

Egg production takes place in the ovaries. It occurs in several steps: 1. Before birth, special cells in the ovaries go through mitosis to make identical daughter cells. 2. The daughter cells then start to divide by meiosis. However, they go though only the first of the two cell divisions of meiosis at this time. They remain in that stage until the girl goes through puberty. 3. After puberty, an egg develops in an ovary about once a month. As you can see in Figure 22.4, the egg rests in a nest of cells called a follicle. The follicle and egg grow larger and go through other changes. 4. After a couple of weeks, the egg bursts out of the follicle and through the wall of the ovary. This is called ovulation. After ovulation occurs, the moving fingers of the nearby fallopian tube sweep the egg into the tube. Fertilization may occur if sperm reach the egg while it is passing through the fallopian tube. If this happens, the egg finally completes meiosis. This results in two daughter cells that differ in size. The smaller cell is called a polar body. It soon breaks down and disappears. The larger cell is the fertilized egg, which will develop into a new human being.

instructional diagrams

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questions

Fertilization of an egg normally takes place while the egg is in the

a. vagin

b. uterus.

c. cervix.

-->  d. fallopian tube.

__structure where fertilization of an egg normally occurs

a. estrogen

b. uterus

c. cervix

d. vagina

e. egg

-->  f. fallopian tube

g. ovary

__cylinder-shaped organ through which a baby passes during birth

a. estrogen

b. uterus

c. cervix

-->  d. vagina

e. egg

f. fallopian tube

g. ovary

Which statement about human eggs is false?

a. Eggs are haploid gametes.

b. Eggs are the largest human cells.

-->  c. There are billions of eggs in each ovary at birth.

d. none of the above

Which statement about the human uterus is false?

a. It is a hollow organ.

b. It has thick, muscular walls.

-->  c. It has just one opening, called the cervix.

d. It can stretch to accommodate a growing baby.

__one of a pair of organs that produce and release eggs

a. estrogen

b. uterus

c. cervix

d. vagina

e. egg

f. fallopian tube

-->  g. ovary

__organ where a fetus develops and grows until birth

a. estrogen

-->  b. uterus

c. cervix

d. vagina

e. egg

f. fallopian tube

g. ovary

Which of the following organs opens directly to the surface of the body?

a. ovary

b. fallopian tube

-->  c. vagina

d. uterus

__female gamete

a. estrogen

b. uterus

c. cervix

d. vagina

-->  e. egg

f. fallopian tube

g. ovary

The structure in which an egg develops inside an ovary is called a

a. fimbri

-->  b. follicle.

c. fallopian tube.

d. none of the above

__small opening that connects the uterus to the vagina

a. estrogen

b. uterus

-->  c. cervix

d. vagina

e. egg

f. fallopian tube

g. ovary

__main female sex hormone

-->  a. estrogen

b. uterus

c. cervix

d. vagina

e. egg

f. fallopian tube

g. ovary

Estrogen causes the changes of puberty in females.

-->  a. true

b. false

Following puberty, an egg is released by each ovary about once a week.

a. true

-->  b. false

Estrogen is secreted by female gonads.

-->  a. true

b. false

To fertilize an egg, sperm must swim from the vagina to an ovary.

a. true

-->  b. false

The menstrual cycle is also called a menstrual period.

a. true

-->  b. false

The main female reproductive organs are inside the body.

-->  a. true

b. false

The male and female reproductive systems have identical functions.

a. true

-->  b. false

Estrogen is needed for an adult woman to release eggs from the ovaries.

-->  a. true

b. false

The ovaries make eggs only after a female has gone through puberty.

a. true

-->  b. false

The upper end of each fallopian tube is attached to an ovary.

a. true

-->  b. false

An egg completes meiosis just before it leaves the ovary.

a. true

-->  b. false

While an egg is developing in a follicle, the lining of the uterus breaks down and passes out of the

a. true

-->  b. false

When a girl is born, how many eggs does each of her ovaries normally contain?

a. none

b. a few

c. about a hundred

-->  d. thousands

Which female reproductive structure secretes estrogen?

a. uterus

b. vagina

-->  c. ovary

d. cervix

An egg reaches the uterus through

-->  a. a fallopian tube.

b. the vagina.

c. the cervix.

d. none of the above

The walls of the uterus

a. can stretch.

b. are muscular.

c. push out a baby during birth.

-->  d. all of the above

For fertilization to take place, sperm generally must be deposited in the

a. ovary.

b. fimbria.

c. uterus.

-->  d. vagina.

A human egg cell

a. contains very little cytoplasm.

b. is a diploid cell.

-->  c. lacks a tail.

d. two of the above

The changes of the menstrual cycle take place in the

a. ovaries.

b. uterus.

c. labium.

-->  d. two of the above

diagram questions

No diagram questions associated with this lesson