biology 3201 15.1 notes human anatomy.notebook
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biology 3201 15.1 notes human anatomy.notebook 1 October 09, 2011 Nov 222:27 PM Human Reproduction Chapter 15 pp 485 Image credit: Dennis Kunkel Nov 222:27 PM Male Reproductive System (see fig. 15.2, p. 487) • Testes – produce sperm and reproductive hormones. 2 parts: • 1. seminiferous tubules – long coiled tubes inside the testes. Spermatogenesis occurs here and inhibin is released from here. These tubules contain Sertoli cells, which support, regulate and nourish developing sperm • 2. interstitial cells – cells surrounding the seminiferous tubules. They produce male hormones like testosterone.
Transcript of biology 3201 15.1 notes human anatomy.notebook
biology 3201 15.1 notes human anatomy.notebook
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October 09, 2011
Nov 222:27 PM
Human Reproduction
Chapter 15 pp 485Image credit: Dennis Kunkel
Nov 222:27 PM
Male Reproductive System (see fig. 15.2, p. 487)
• Testes – produce sperm and reproductive hormones. 2 parts: • 1. seminiferous tubules – long coiled tubes inside the testes. Spermatogenesis occurs here and inhibin is released from here. These tubules contain Sertoli cells, which support, regulate and nourish developing sperm • 2. interstitial cells – cells surrounding the seminiferous tubules. They produce male hormones like testosterone.
biology 3201 15.1 notes human anatomy.notebook
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October 09, 2011
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Male Reproductive System
• Scrotum – sac which holds testes outside the body. Sperm develop in temperatures slightly cooler than body temperature. However, if the environment is too cold, the scrotum can be retracted so the testes are held closer to the body • Epididymis – the tube within the scrotum in which sperm mature and become mobile
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Male Reproductive System
• Vas deferens – the tube which carries sperm from the epididymis to the urethra • Prostate gland – a gland that secretes an alkaline fluid which neutralizes the acidity within the female reproductive system • Cowper’s gland (bulbourethral gland) – same as prostate • seminal vesicles – glands that produce mucuslike fluid containing fructose as energy for sperm
biology 3201 15.1 notes human anatomy.notebook
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October 09, 2011
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Male reproductive system
• semen – fluid consisting of sperm and fluid from the prostate, seminal vesicles, and Cowper’s gland • urethra – tube which carries sperm into female reproductive system (also used in excretory system) • penis – transfers sperm to female reproductive system during sexual intercourse
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biology 3201 15.1 notes human anatomy.notebook
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Male Reproductive Hormones
• 1. Inhibin hormone that acts on the hypothalamus to slow down the production of release factors that trigger FSH secretion. It is released by the seminiferous tubules. • 2. Folliclestimulating hormone (FSH) – in males, FSH increases sperm formation (released by the anterior pituitary) • 3. Lutenizing hormone (LH) – produced by the anterior pituitary; LH stimulates interstitial cells to produce testosterone
biology 3201 15.1 notes human anatomy.notebook
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Male Reproductive Hormones
• 4. Testosterone – steroid hormone produced in the testes that is responsible for secondary sex characteristics in males, such as • enlargement of primary sex characteristics • enlargement of larynx (Adam’s apple) • inhibiting fat storage and increasing muscle development • formation of hair on chest, arms, face, genitals
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Female Reproductive System (see fig. 15.5, p. 490)
• Ovary – gland that is suspended in the abdominal cavity and produces eggs (ova) • Follicles – in the female reproductive system, groups of cells held in the ovaries. Each of these cells contain an ovum that will develop • Oviducts (Fallopian tubes) – pair of tubes in the body that transport an egg from the ovary to the uterus. Fertilization of eggs occurs here. Oviducts are ciliated to help eggs travel.
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Female Reproductive System
• Fimbriae – fingerlike projections that sweep eggs from where they exit the ovaries into the oviducts • Uterus – the womb. After an egg is fertilized, it attaches to the uterine wall and grows. Usually it is the size of a fist, but it expands to six times that size to accommodate a fetus.
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Female Reproductive System
• Endometrium the mucous membrane that lines the uterus and increases in thickness in the latter part of the menstrual cycle • Cervix – the opening/exit of the uterus • Vagina – the birth canal; an entrance for an erect penis to deposit sperm during sexual intercourse and an exit for the fetus during childbirth.
biology 3201 15.1 notes human anatomy.notebook
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October 09, 2011
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biology 3201 15.1 notes human anatomy.notebook
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October 09, 2011
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Nov 222:27 PM
biology 3201 15.1 notes human anatomy.notebook
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October 09, 2011
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Nov 222:27 PM
biology 3201 15.1 notes human anatomy.notebook
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October 09, 2011
Nov 222:27 PM
Female Hormones
• 1. follicle stimulating hormone (FSH) – in females, FSH is responsible for the follicles developing and secreting estrogen • 2. lutenizing hormone (LH) – in females, LH triggers the release of an ovum from the follicle
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Female Hormones• 3. estrogen – produced by the follicles; responsible for the thickening of the endometrium and keeps FSH secretions down (to prevent further follicles from developing) • 4. progesterone – sex hormone that is produced in females, first by the corpus luteum and the ovary to prepare the uterus for fertilization, and later by the placenta to maintain pregnancy
