Reproductive System. Before the Bell: Get out your workbook. Ground Rules -Appropriate and mature behavior/comments is expected. -Anatomical terms will be used. -Questions that might involve values, ethics, beliefs, etc. I will not answer but will refer home. Pg. 128.
Before the Bell:
Get out your workbook.
-Appropriate and mature behavior/comments is expected.
-Anatomical terms will be used.
-Questions that might involve values, ethics, beliefs, etc. I will not answer but will refer home.
The Reproductive System
Reproduction is the process by which life is continued from one generation to the next.
A new human life results from the union of two specialized cells, one from a male and the other from a female. These cells, the egg and the sperm, are produced by the reproductive system, the organs that make possible the production of offspring.
The Male Reproductive System
Sperm are produced in the testes and mature in the epididymis.
From there, they travel through the vas deferens, where they are mixed with seminal fluid, which is produced by the seminal vesicles, the prostrate gland, and Cowper’s glands. This mixture of sperm and seminal fluid is called semen. Muscular contractions force semen through the urethra and out of the body, a process called ejaculation.
Day 14 of the cycle, ovulation occurs.
Day 15 –20, the egg travels through the fallopian tube.
Day 21, the egg enters the uterus.
The Menstrual Cycle
The menstrual cycle is the sequence of events in the reproductive system that occurs from one menstruation to another. A cycle usually lasts about 28 days, but it varies from one female to another.
After 7 days, if the egg has not been fertilized, menstruation begins.
Most females begin menstruation between the ages of 9 and 16. Menstruation occurs from puberty until menopause.
Menopause, which usually occurs between age 40 and 60, is a period marking the end of a female’s reproductive years.
Fertilization is the joining of a male and female reproductive cell to make the first cell of a new human.
This cell, the fertilized egg, then moves down the fallopian tube and into the uterus. The fertilized egg attaches to the wall of the uterus and begins to grow.
In the early stages, the fertilized egg is called an embryo. After eight weeks of development, it is called a fetus. The uterus has layers of tissue and a rich blood supply to nourish the developing fetus. After about 40 weeks, the fetus is mature and ready to be born. The walls of the uterus begin to contract. The contractions open the cervix and push the baby out of the uterus and through the cervix. The baby passes through the vagina and out of the female’s body.
Soon after fertilization, the cell begins to divide. It forms a cluster of cells that attaches itself to the inside wall of the uterus. The cluster of cells is now called an embryo. These cells continue to divide and form cells that do specific jobs.
Over time, cells that do similar jobs combine into tissues, tissues with similar jobs combine into organs, and organs with similar jobs combine into systems.
A fetus is the name for the developing organism from the end of the eighth week until birth. The baby is born about nine months after fertilization.
Growth inside the Uterus
Food and oxygen in the mother’s blood are carried to the fetus through a blood vessel in the umbilical cord, a tube that connects the fetus and the mother’s placenta. After birth, the cord is cut.
Complete questions on pg. 144.