ME Sci 10 Q3 1002 SG PDF - Grade 10 Science: Male Reproductive System

Science Grade 10 Unit 10: Human Reproductive System LESSON 10.2 Male Reproductive System Table of Contents Introduction 1 Learning Competency...

Science Grade 10 Unit 10: Human Reproductive System LESSON 10.2 Male Reproductive System Table of Contents Introduction 1 Learning Competency 2 Learning Objectives 2 Warm-Up 2 Learn about It 3 Components of the Male Reproductive System 3 Testes 3 Scrotum 5 Epididymis 6 Vas Deferens 7 Prostate Gland 7 Urethra 7 Penis 7 Sperm Ducts 8 Accessory Glands 8 General Functions of the Male Reproductive System 9 Production of Sperm Cells 9 Production of Hormones 9 Deposition of Sperm Cells 9 Key Points 10 Check Your Understanding 10 Photo Credit 12 Bibliography 12  Science Grade 10 Unit 10: Human Reproductive System Lesson 10.2 Male Reproductive System A sperm (stained in the photo for laboratory test) is the gamete produced by the male reproductive system. Introduction The female reproductive system is designed not only to reproduce gametes and female hormones but also to carry and nourish an offspring. The male reproductive organs, on the other hand, serve a more distinct purpose compared with that of females. The male reproductive system is for producing male gametes called sperm cells and delivering them to 1  Science Grade 10 Unit 10: Human Reproductive System the female reproductive tract. As a result, reproductive organs differ in structure and appearance. What are the components and functions of the male reproductive system? As you progress in this lesson, you will be able to answer this question. Learning Competency At the end of this lesson, the given enabling competency should be met by the students. Describe the parts and functions of the human reproductive system. Learning Objectives In this lesson, you should be able to do the following: Discuss the parts of the male reproductive system and their functions. Discuss the functions of male reproductive system that differentiate it from the female reproductive system. Warm-Up Male Reproductive System Puzzle Materials puzzle printouts Procedure 1. Each group should secure a printout of the male reproductive system from the link below. 2  Science Grade 10 Unit 10: Human Reproductive System Male Reproductive System Exercise https://drive.google.com/file/d/1Qg73judrvLkvOLJ4hiQjFMX-5 cstMVVE/view?usp=sharing 2. Cut out the components or organs from the printout and then arrange them properly. Your end product should form the male reproductive system. 3. Brainstorm ideas about the functions of these components. 4. Trace the path of the sperm cells from the testes. Guide Questions 1. Where do you think the sperm cells are produced? 2. What are all these organs for? Learn about It Essential Question What are the components of the male reproductive system and their general functions? Components of the Male Reproductive System The male reproductive system has organs that fulfill the functions that were mentioned above. It is composed of the testes, scrotum, prostate gland, urethra, penis, and sperm ducts. Testes Recall that the gonads of the male reproductive system are the testes (sing. testis). The male reproductive system has two testes. Their function is to produce male sex cells, the sperm cells. They also produce male sex hormones, such as testosterone. 3  Science Grade 10 Unit 10: Human Reproductive System Fig. 1. Organs of the male reproductive system The sperm cells develop inside the testes in a series of tubes known as the seminiferous tubules. The seminiferous tubules are structures that are coiled inside the testes and where sperm is produced and mature. Immature sperm cells are commonly found near the border of the seminiferous tubules. As these cells mature, they move farther inside the tubules, closer to the lumen, which refers to the space in the middle of a tube. Fully mature sperm cells, those that are motile and have developed flagella, are found within the lumen. Other cells, such as the Sertoli cells, Leydig cells, and myoid cells, can also be found in the testes. The Sertoli cells release a variety of hormones that aid in the development of sperm cells, and the Leydig cells primarily release testosterone. The myoid cells are for the contraction of the seminiferous tubules for moving cells and substances. There are also 4  Science Grade 10 Unit 10: Human Reproductive System blood vessels in the testes for the delivery of oxygen and nutrients. Fig. 2. Cross-section a seminiferous tubule Scrotum The scrotum is a bag of skin that contains the testes. It is a reproductive structure that is located under the penis. The scrotum is about 2°C to 3°C, which is lower than the normal body temperature. This is the temperature that is favorable for sperm cell production and development. Fig. 3. Dartos and cremaster muscles of the scrotum 5  Science Grade 10 Unit 10: Human Reproductive System Within the scrotum are muscles known as the dartos and cremaster muscles. These play important roles in maintaining the temperature of the scrotum. When the environmental temperature is significantly low, the dartos contract, decreasing the surface area of the scrotum in contact with the outside environment. This condition prevents further heat loss. The cremaster, on the other hand, brings the testes closer to the body to conserve heat. Epididymis Mature sperm cells are later on stored in a tube beside the testes known as the epididymis. The sperm cells are stored until they are released from the body through a process known as ejaculation. Ejaculation forcefully expels sperm cells and semen from the male body into the female’s vagina during sexual intercourse. This forceful expulsion of fluid is made possible by muscles, such as the pubococcygeus and the bulbospongiosus muscles. Once the sperm cells are within the female reproductive tract, they can survive as long as five days. This increases the chances of successfully fertilizing an egg. If the sperm cells remain within the male reproductive system for too long, they become phagocytosed and are reabsorbed back by the system. This is to ensure that the sperm cells that can potentially fertilize an egg are not at an advanced age. The epididymis contains proteins known as defensins. There are many kinds of defensins, and all of them are found in different areas of the body and perform different functions. The defensins in the epididymis support the reproductive tract of male, protect against bacterial infections, and regulate recovery after a bacterial infection. 6  Science Grade 10 Unit 10: Human Reproductive System Vas Deferens During ejaculation, sperm cells move from the epididymis into a tube called the vas deferens, into another tube known as the urethra, and out of the body. Vasectomy is a method of birth control that involves cutting or blocking the tubes of the vas deferens. This prevents the sperm cells from being transported out of the body and results in future sexual intercourse by the affected male to carry no risk of fertilization. Prostate Gland The prostate gland secretes the prostate fluid, which neutralizes the acidic conditions of the vagina. The mixture of sperm and prostate fluid is called semen. The muscles of the prostate gland help propel the semen through the urethra and into the female reproductive organ during ejaculation. Urethra The urethra is the tube that transports and discharges urine and semen outside the body. It is connected to both the urinary bladder and the sperm duct. This is the reason why the urethra serves as an exit point for both urinary and reproductive products. Penis The penis is the external part of the male reproductive system. It is a tube-shaped organ that contains the urethra, allowing the urine and semen to pass through and leave the body. The glans penis, also known as the head of the penis, is a sensitive structure at the end of the organ. It contains the opening for the urethra. The glans penis is covered by an excess skin known as the prepuce, which protects the glans. 7  Science Grade 10 Unit 10: Human Reproductive System Within the penis is a structure known as the corpus cavernosum (plural: corpora cavernosa). This structure is the erectile tissue in men, which leads to the penis becoming erect when the corpora cavernosa is filled with blood. This is in preparation for sexual intercourse. Many cultures practice a medical process known as circumcision. This process involves the partial or complete removal of the prepuce to expose the glans penis. Studies show that circumcision has many medical benefits, which include decreased risk of some diseases and infections. Sperm Ducts Sperm ducts are composed of the vas deferens and seminal vesicles. Recall that the vas deferens is a tube through which the sperm cells pass before entering the urethra. On the other hand, seminal vesicles secrete a fluid that makes the sperm cells more mobile, increasing the chances of fertilization. The spermatic cord is a structure associated with the vas deferens. Its primary function is to hold and support structure, such as blood vessels and the vas deferens. Accessory Glands The male reproductive system also has accessory glands, which secrete substances that aid in the nourishment of the sperm cells and contribute to higher chances of fertilization. The seminal vesicles are considered as accessory glands. Other accessory glands include the bulbourethral gland and the prostate. The bulbourethral gland has secretions that neutralize the acidity of the vagina, whereas the prostate gland releases substances that increase the motility of the sperm cells. In terms of the composition of human semen, it consists of 5% secretions from bulbourethral glands, 30% from prostate glands, and 65% from the seminal vesicle. 8  Science Grade 10 Unit 10: Human Reproductive System Remember The ejaculate or semen is a mixture of the sperm cells and the fluids released by the accessory organs of the male reproductive system. The fluids mixed with the sperm cells aid the sperm cells in the journey to fertilize the egg cell. General Functions of the Male Reproductive System The male reproductive system is specialized for the production of sperm cells and their deposition into the female reproductive tract. It has a series of structures that performs these functions efficiently. Production of Sperm Cells As mentioned, the sperm cells are produced by the male reproductive system. It also allows for the development and maturation of these cells. Recall that this process is known as gametogenesis, and the type of gametogenesis that occurs in male organisms is known as spermatogenesis. Production of Hormones The primary male sex hormone is testosterone, and it is produced by the testes. Testosterone is responsible for the changes that occur during puberty, as well as the signaling that is necessary to trigger spermatogenesis. Deposition of Sperm Cells Another function of the male reproductive system is to safely and properly deposit the sperm cells into the female reproductive tract. The male reproductive system has a number of secretions to ensure that the sperm cells are properly nourished and protected for them to be safely deposited into the female reproductive tract. As mentioned, the penis does the deposition. Any organ that is used for depositing sperm cells into a female is known as an intromittent organ. This is the penis in humans. 9  Science Grade 10 Unit 10: Human Reproductive System Key Points The male reproductive system is specialized for the production of sperm cells and their deposition into the female reproductive tract. The production, development, and maturation of sperm cells happen within the male reproductive system. The type of gametogenesis that occurs in male organisms is known as spermatogenesis. The male reproductive system is composed of the testes, scrotum, urethra, penis, sperm ducts, and accessory glands. The gonads of the male reproductive system are the testes. The male reproductive system consists of two testes. Check Your Understanding A. Identify the terms being described by the statements below. 1. These are the male gametes. 2. This refers to the formation and development of gametes in males. 3. This holds the gonads of the male. 4. This is where the sex cells of the male develop in the gonad. 5. This is where mature sex cells are stored. 6. This is the release of male sex cells from the body. 7. This is the exit tube of the sex cells from the male body. 8. This gland secretes prostate fluid. 9. This is the tube-shaped external organ of the male reproductive system. 10. These secrete the fluid that makes the sperm cells more mobile. 10  Science Grade 10 Unit 10: Human Reproductive System B. Write true if the statement is accurate and false if it is otherwise. 1. Males have a significant amount of estrogen. Answer: false 2. The exit points for urine and sperm are different. Answer: false 3. The sperm ducts include the seminal vesicles and the vas deferens. Answer: true 4. Prostate fluid neutralizes vaginal acidity. Answer: true 5. The scrotum is an internal organ. Answer: false 6. Most of the semen consists of secretions from the bulbourethral glands. Answer: false 7. The prostate gland is the male gonad. Answer: false 8. The semen functions to protect and nourish the sperm cells. Answer: true 9. The penis is part of the male external genitalia. Answer: true 10. Sperm production is possible if the testes stay in the abdomen. Answer: false 11  Science Grade 10 Unit 10: Human Reproductive System Photo Credit Introduction Photo. Sperm stained.JPG by Bobjgalindo is licensed under CC BY-SA 4.0 via Wikimedia. Bibliography Concord-Carlisle High School. Reproductive System Grades 9-12, Lesson 2. http://www.concordcarlisle.org/jreed/wp-content/uploads/sites/37/2015/01/Reprodu ctive-System-.pdf Heffner L. and Danny J. Schust. The Reproductive System at a Glance (3rd edition),. Singapore: Wiley-Blackwell. 2010. O’Donnell K. The Reproductive System. New York: The Rosen Publishing Group, Inc. 2011. The Human Body: The Reproductive System. Britannica Educational Publishing, 2011. 12