Reproductive System Ch 19 General Functions of reproductive

Reproductive System Ch 19

General Functions of reproductive system. � Produce and nurture sex cells � Gametes � Sperm � Eggs � Transport them to sites of fertilization.

Meiosis - Overview � Creates sex cells with half the number of chromosomes as normal cells. 46 � Haploid � Two 46 -46 divisions 23 -23 � Males: 23 -23 Spermatogenesis � Females: Oogenesis 23 23

Meiosis - Sperm

Meiosis - Egg

Locate and describe the general functions of each part of the male reproductive system � testes � ductus � epididymis � urethra � scrotum � corpus � bulbourethral gland � prostate gland � seminal vesicle deferens cavernosum � corpus spongiosum � penis � glans penis

Outline the process of spermatogenesis. � spermatogenesis – formation of sperm � Spermatogenic cells (spermatogonia) formed in the testes (46 chromosomes) � At puberty when testosterone production resumes. . . � Form primary spermatocytes � Meiosis takes place � First division makes secondary spermatocytes � Second division makes spermatids (23 chromosomes)

Outline the process of spermatogenesis. � When spermatids reach the epididymis, they are non -motile. � By the time they are pushed through the epididymis, they have matured into sperm cells and can move independently.

Describe semen production and exit from the body. � Production takes place in four parts: � Testes – sperm � Seminal vesicles � Prostate gland � Bulbourethral glands � Exits by ejaculation through the penis.

Vocabulary � spermatogenesis � spermatogonia � spermatid

Explain how hormones control the activities of the male reproductive organs… � Gn. RH – released in hypothalamus � Pituitary gland– secretes gonadotropins � In males, these are androgens � LH (leutinizing hormone) � FSH (follicle-stimulating hormone) � Testosterone

…and the development of male secondary sex characteristics � Body hair � Lower voice � Thickening of skin � Increased muscular growth � Thickening/strengthening of bones

More about hormones � There’s a negative feedback system that controls the amount of testosterone released.

Locate and describe the general functions of each part of the female reproductive system � Endometrium � Ovaries � Uterine � Uterus � Cervix � Vagina � Clitoris tube � Myometrium � Perimetrium

Outline the process of oogenesis. � What is oogenesis? � Primordial follicles are formed during fetal development. These are also calle primary oocytes. � At puberty, primary oocytes continue meiosis. � Cytoplam is distributed unevenly, so only one secondary oocyte is formed.

Meiosis - Egg

Outline the process of oogenesis. � Secondary oocyte is released from the ovary – Ovulation � Uterine tubes – fertilization � IF it’s fertilized, it will go through Meiosis II and become a zygote. � Only have about a day! � Uterus � Three – receives embryo and sustains development layers � Endometrium � Myometrium � Perimetrium � Vagina – birthing purposes and receives sperm

Explain how hormones control the activities of the female reproductive organs. . . � Puberty – FSH is released and ovaries enlarge � LH triggers ovulation. � Two main types of female hormones – estrogens and progesterones. � Ovaries are the major source of estrogens. � They stimulate enlargement of vagina, uterus, uterine tubes, and ovaries. � They develop secondary sex characteristics.

. . . and the development of the female secondary sex characteristics. � Development of breasts and ductile system of mammary glands � Increased deposition of adipose tissue generall, and specifically in the breasts, thighs, and buttocks. � Increased blood vessels in skin. � Females also have a low androgen concentration that stimulates hair growth in pubic and axillary regions.

Vocabulary � Spermatogenesis � Ovulation � Spermatid � Androgen � Spermatogonia � Testosterone � Oogenesis � Estrogen � Oocyte � Progesterone

Describe the major events of the reproductive cycle. � FSH and LH released from pituitary gland. � FSH causes follicle to become primary oocyte. � Follicular cells secrete estrogen causing endometrium to thicken. � More LH from pituitary gland stimulates ovulation. � More estrogen and progesterone is released – waiting for fertilization.

Describe the major events of the reproductive cycle. � If fertilization does not occur, estrogen and progesterone stop – causes endometrium to quit building. � Uterine lining disintegrates and sloughs off. � Cylce repeats with LH and FSH being released from pituitary.