Male and Female Reproductive System And Fertilization and

Male and Female Reproductive System And Fertilization and Development

Sexual Development � At first male and female human embryos are identical in appearance. � During the ____________, the reproductive systems of male and female embryos begin to develop. � The male pattern of development is triggered by the production of testosterone in the gonads (makes gametes) of the embryo.

Sexual Development � Testosterone and Estrogens have powerful effects on the body. � Effects of hormones: ◦ Growth of facial hair ◦ Increased muscular development ◦ ________________ ◦ Breast development ◦ _______________

Sexual Development � Puberty ◦ Period of rapid growth and sexual _________ ◦ When reproductive system becomes fully functional ◦ Begins in the ______ when hypothalamus signals the ______ to produce 2 hormones that affect the gonads. ◦ Between ages of 9 and 15 ◦ Females begin 1 year earlier than males

Holds urine Sperm pathway Skin sac that holds testicles And vessels Make fluid for semen Produces sperm & male hormone Sperm mature & travel through

Sexual Development � What are the main functions of the male reproduce system? ◦ When puberty is complete, the reproductive system is fully functional, ◦ Meaning the male can produce and release ____________.

Female Reproductive System � Ovaries: � Main primary reproductive organs function: _________, or ova (singular-ovum) ◦ Prepares the body to nourish a developing embryo

Pathway for egg: fertilization occurs Fetus grows inside Produces egg & female hormones Dilates in labor Allows for flow of menstrual blood & sexual intercourse

Female Reproductive Structures � At puberty, each ovary has as many as 400, 000 primary follicles that surround a single egg. � The function of a follicle is to help an egg mature for release and fertilized by a sperm.

Female Reproductive Structures � Other ◦ ◦ structures: Fallopian tubes ____ Cervix ____

Menstrual Cycle � One ovary produces and releases one mature ovum every 28 days or so. � Menstrual Cycle: ◦ Process of egg formation and release ◦ Regulated by hormones made by the hypothalamus, pituitary, and ovaries � Cramps � Painful caused by cramping is caused by clots or bloody tissues pass through the cervix.

Menstrual Cycle pg. 991 � During the menstrual cycle; ◦ An egg develops within a follicle and is released from an ovary. ◦ Uterus is prepared to receive the fertilized egg. ◦ Embryonic development begins and the cycle stops.

Pregnancy � Menstrual cycle also stops when a woman is _______. � If a sperm fertilizes an egg, it completes meiosis and undergoes mitosis. �A ball of cells will form an implant itself in the lining of the uterus. � After implantation, the embryo grows and prevents the menstrual cycle to begin again.

Fertilization and Development � What takes place during fertilization and the early stages of human development? ◦ The fusion of a sperm and egg cell is called _________.

Fertilization � 1. During sexual intercourse, sperm are released when semen enters the vagina. � 2. The egg is surrounded by a protective layer with binding sites for sperm to attach. � 3.

Fertilization � 4. The haploid (N) sperm nucleus enters the haploid egg, and chromosomes of sperm and egg join together. � 5. The 2 haploid nuclei fuse and a single diploid (2 N) is formed with a single set of chromosomes from each parent cell. � 6. ______: fertilized egg. At this point the developing human is called an embryo.

Later Development � What important events occur during the later stages of human development?

� First Trimester: � Second Trimester: � Third Trimester:

Months 4 -6 � The tissues of the fetus become more complex and specialized, and begin to function. ◦ The fetal heart becomes large enough so that it can be heard with a __________. ◦ Bone replaces cartilage that forms the ______________. ◦ Layer of soft hair grow. ◦ Mother feels the fetus moving.

Months 7 -9 � The organ systems of the fetus mature. � Fetus grows in size and mass. � Regulate _________. � 8 months= premature