Reproduction
Sexual reproduction is the process by which the genetic material from two organisms, a male and a female, combine to create an offspring; otherwise known as fertilization. A male's sex cells, or gametes, are called sperm and a female's sex cells are called ova. A human’s genetic material contains 46 chromosomes, or 23 pairs of chromosomes that are combined to create one pair of sex chromosomes. Females have two X chromosomes, while males have an X and a Y chromosome. How many chromosomes does each parent contribute?
Gender Determination
Each gamete only carries one sex chromosome. Because females contain XX and males are XY, it is the male who becomes the dominant contributor in the genetic makeup for development of an offspring. If a sperm with a Y chromosome fertilizes an ovum, the zygote is male. If a sperm with an X chromosome fertilizes an ovum, the zygote is female.
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The Human Reproductive System
Female Reproductive System
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Male Reproductive System
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The female Reproductive System contains the ovaries, the fallopian tubes, the uterus, the vagina and the cervix. The roll of the ovaries is to maintain the immature eggs (ova) and to produce the female reproductive hormones; progesterone and estrogen. The fallopian tubes connect the ovaries to the uterus and their main purpose is to guide the ova. The uterus is a hollow organ that houses and nurtures the developing fetus. The vagina, or birth canal, connects to the uterus via the cervix. What is the main function of progesterone? Of Estrogen?
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Male Reproductive System contains the testes, seminal vesicles, prostate and the penis. The testes produce sperm and the male productive hormone; testosterone. The seminal vesicles and prostate secrete seminal fluid that mixes with sperm to form semen. The penis is the organ used for sexual intercourse that contains erectile tissue. What is the primary function of Testosterone? How many sperm are in one ejaculate? How long can sperm survive within a female's reproductive system?
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The Menstrual Cycle
The Menstrual Cycle is a sequence of changes controlled by the female’s sex hormones. Ovarian follicles begin developing and at the midpoint of the menstrual cycle, ovulation. What is ovulation? How long does it last? If no fertilization occurs, the female's hormones decrease, and menstruation begins. Menstruation is the sloughing off of the endometrial lining of the uterus. Common symptoms of Menstrual Disorders are lack of menstruation, painful, irregular menstrual periods, excessive bleeding, changes in mood and depression or anxiety. Premenstrual Syndrome (PMS) usually occurs before menstruation and includes cramps, mood changes and bloating. Describe Premenstrual Dysphoric Disorder (PMDD)?