Human Reproduction: Puberty and Hormones

• Key entities of the human reproductive system include the penis, vagina, scrotum, semen, testes, and sperm.

Puberty

• Puberty refers to the period when hormones instigate physical changes in the human body, leading to the development of secondary sex characteristics, which enable the body to produce gametes.
• Puberty in males typically occurs between 12-14 years of age.
• Puberty in females usually occurs between 10-14 years of age.

Secondary Characteristics in Females

• Development of breasts (mammary glands).
• Changes in body form, including hips and thighs.
• Growth of body hair.

Secondary Characteristics in Males

• Growth of beard and other body hair.
• Changes in lower form and muscles.
• Lower voice pitch.

Hormones

• Human reproduction is controlled by hormones secreted by the gonads (testes and ovaries).
• Reproduction starts with gametes: eggs and sperm.

Male Reproductive System

• Main functions are to produce sperm and deposit sperm inside the female reproductive tract.
• Sperm is produced in the testes, which are housed in a sac called the scrotum.
• The scrotum maintains the optimal temperature for sperm production.
• The prostate produces seminal fluid, a component of semen.
• The prostate plays a role in hormone production and helps regulate urine flow.

Female Reproductive System

• The main function is to produce eggs and provide the site for fertilization and embryonic development.
• Eggs are produced in the ovaries, within structures called follicles.
• Ovulation is when an egg is released.
• After release, the egg passes through the oviduct or fallopian tube.
• The uterus, also known as the womb, has thick walls and is shaped like a pear, and it is where the embryo develops.
• The cervix, which is the lower end of the uterus, opens into a muscular tube called the vagina.

Menstrual Cycle

• Occurs roughly every 28 days.
• Hormones regulate the changes in the ovaries and uterus during the menstrual cycle.
• The menstrual cycle starts at puberty and ends at menopause.
• A lack of menstrual cycle indicates possible fertilization.
• Egg + Sperm = Fertilization results in a Zygote = a Baby.

Pregnancy

• Not all women experience the same pregnancy symptoms.
• Possible pregnancy symptoms include:
  • Missing a menstrual period.
  • Tender and swollen breasts.
  • Feeling very tired
  • Feeling sick to your stomach and/or vomiting.
  • More frequent urination.

Pregnancy and Childbirth

• Pregnancy refers to the carrying of one or more offspring from fertilization to birth.
• Prenatal care is important to avoid risks during pregnancy.
• Pregnant women require abundant vitamins and minerals for their and their baby/babies' health.
• The uterus or womb serves as the gestation period location.
• Milestones occur during each trimester, which is roughly every three months.
• Labour starts with contractions of the muscle wall and dilation of the cervix.
• Contractions during labour become more intense and frequent until dilation is complete.
• A baby is ready to be born once dilation is complete.
• The placenta is an organ that allows the exchange of nutrients/wastes between the mother and embryo and secretes hormones to stop menstruation during pregnancy.
• The umbilical cord connects the fetus to the placenta.
• Amniotic fluid is a clear, slightly yellowish fluid surrounding the fetus during pregnancy protects the baby by absorbing shock.
• Gestation is the length of pregnancy, for humans it is 9 months, for an Elephant it is 21 months and Sea Turtles is 2 months
• Fraternal twins are from 2 different eggs. -Identical twins are when 1 egg divides into 2 embryos.
• Some complications include: -High Blood Pressure -Gestational Diabetes -Infections -Preeclampsia -Preterm Labor -Mental Health -Miscarriage -Stillbirth -Anemia