andi :]

12/2/2025

Biology

The Reproductive System Notes and Diagrams

•

Dec 2, 2025

•

7 pages

Understanding the Reproductive System: Notes and Diagrams

andi :]

@snuggly_bunbun

The reproductive system is responsible for producing sex hormones and... Show more

1 / 7

Reproductive System
●
●
●
●
●
Male Anatomy
Scrotum
O
●
Secrete Sex Hormones
Gonads
O
Male - Testes
O Female Ovaries
●
Gametes
●
o Male - Spe

Male Reproductive Anatomy

Ever wondered how the male reproductive system keeps everything functioning? It starts with the testes, which serve two critical purposes: producing sperm (reproductive function) and testosterone (endocrine function). These oval-shaped organs are housed in the scrotum, a pouch of skin that maintains a cooler temperature necessary for viable sperm production.

The penis consists of three main parts: the root (where it connects to the abdomen), the shaft (the main length), and the glans (the enlarged tip). During arousal, spongy erectile tissue fills with blood, causing the penis to become rigid and enlarged. This process becomes less efficient with age as blood circulation weakens.

Sperm production begins in the seminiferous tubules within the testes. From there, sperm follows a specific pathway: testes → epididymis → vas deferens → urethra → outside. Low testosterone can cause several issues including decreased sperm count, reduced sex drive, and changes in muscle mass, fat distribution, and bone density.

Health Note: Circumcision (removal of the foreskin from the glans) offers several health benefits including easier hygiene and lower risk of urinary tract infections and sexually transmitted infections.

Sperm Production and Male Fertility

The journey of sperm is fascinating! After formation in the testes, sperm travels to the epididymis, a coiled tube behind the testes where sperm matures and is temporarily stored. From there, sperm moves through the vas deferens before eventually reaching the urethra for ejaculation.

Semen is much more than just sperm—it's a complex fluid with a basic pH of 7.6 to neutralize the acidity of the vagina. Healthy semen contains between 50-150 million sperm per milliliter and includes nutrients from several accessory glands. The seminal vesicles provide fructose for energy, the prostate gland adds additional nutrients, and the bulbourethral glands produce lubricating fluid.

Male infertility occurs when sperm count falls below 20 million per milliliter. Doctors analyze several factors during fertility testing: sperm count, motility, shape, semen volume, fructose content, and pH level. Infertility can result from duct system obstructions, hormonal imbalances, or lifestyle factors like excessive alcohol consumption.

Health Alert: An enlarged prostate can press against the urethra and weaken the bladder, leading to frequent urination and inability to fully empty the bladder—a common concern as men age.

STIs and Female Reproductive Anatomy

Human Papillomavirus (HPV) is a common sexually transmitted infection that often causes no symptoms but can lead to serious complications. HPV is linked to several cancers including cervical, genital, anal, and oropharyngeal cancer. Prevention involves vaccination and using condoms correctly during sex.

The female reproductive system begins with approximately 250,000 primary oocytes (immature eggs) that remain dormant until puberty. When puberty begins, hormones trigger the maturation of follicles holding these oocytes, beginning the ovulation cycle. Throughout a woman's reproductive period—from puberty until around age fifty—only about 500 ova (mature eggs) will be released.

Once released, eggs travel through the fallopian tubes toward the uterus. These tubes are the site of fertilization, where sperm and egg may meet. The fallopian tubes transport the egg (or fertilized embryo) to the uterus through wave-like muscle contractions called peristalsis.

Health Warning: "Super Gonorrhea" is a concerning new strain of gonorrhea resistant to many common antibiotics. This STI spreads through sexual contact and can cause serious complications if left untreated, including potential infertility in women.

Female Reproductive Health Concerns

Gonorrhea can affect various parts of the female body with different symptoms. Vaginal infections might cause painful urination, increased discharge, or bleeding between periods. Rectal infections can result in discharge, itching, and painful bowel movements. If untreated, gonorrhea can lead to Pelvic Inflammatory Disease (PID), causing abdominal pain, fever, and potential damage to the fallopian tubes.

The female reproductive pathway flows from the fallopian tubes to the uterus and then to the vagina. The uterus serves to receive, retain, and nourish a fertilized egg. It has three main areas: the fundus (superior portion), body (majority), and cervix (inferior portion). The innermost layer of the uterus wall, called the endometrium, is where a fertilized egg implants during pregnancy.

Reproductive health complications can include ectopic pregnancy, where an egg implants somewhere outside the uterus, potentially causing dangerous internal bleeding. Another concern is tubal ligation, a sterilization procedure where fallopian tubes are severed from the uterus, preventing eggs from reaching the uterus.

Health Insight: When bits of endometrium grow outside the uterus onto other organs, it results in endometriosis—a condition causing intense cramping and pelvic pain that affects millions of women worldwide.

Female Health Screenings and STIs

Pap smears are vital screening tests where doctors take cell samples from the cervix to detect cervical cancer. Many factors increase cervical cancer risk, including HPV infection, multiple sexual partners, early sexual activity, smoking, and long-term birth control use. Regular screening is essential for early detection.

The vagina connects the uterus to the external genitalia, with the hymen located at its superior end. It's important to note that females do not release urine from their vaginas—the female urethra opens a few inches above the vaginal opening. The perineum is the area between the vaginal opening and anus, which sometimes requires an episiotomy (surgical cut) during childbirth to prevent tissue damage.

Syphilis progresses through several stages if left untreated. The primary stage features a painless genital ulcer called a chancre. The secondary stage involves skin rashes, fever, swollen lymph nodes, and other symptoms. After a latent (asymptomatic) period, untreated syphilis can advance to tertiary syphilis, potentially affecting the brain, heart, and other vital organs.

Health Trend: Syphilis rates have been rising due to decreasing condom use, limited healthcare access, and increasing substance abuse—making awareness and prevention more important than ever.

Advanced STI Complications

Untreated syphilis can lead to serious complications affecting multiple body systems. Tertiary syphilis can damage the brain, nerves, eyes, heart, blood vessels, liver, bones, and joints—potentially years after initial infection. This highlights the importance of early detection and treatment.

Neurosyphilis affects the nervous system, causing severe headaches, muscle weakness, numbness, confusion, and even personality changes or dementia. Ocular syphilis impacts vision with symptoms like eye pain, floating spots, and sensitivity to light. Otosyphilis can lead to hearing loss, tinnitus, balance difficulties, and vertigo.

Several factors contribute to the rising rates of syphilis infections. Decreasing condom use leaves people vulnerable to STI transmission. Limited access to healthcare means many infections go undiagnosed and untreated. Additionally, increasing substance abuse is associated with higher-risk sexual behaviors that can lead to STI transmission.

Prevention Note: Regular STI testing, consistent condom use, and prompt treatment are the most effective ways to prevent long-term complications from syphilis and other sexually transmitted infections.

Reproductive System Diagrams

The male reproductive system features several interconnected structures. The external components include the penis, scrotum containing the testicles, and the glans. Internally, the vas deferens connects to the seminal vesicles and prostate gland before joining the urethra. The epididymis sits adjacent to each testicle, storing maturing sperm.

Female reproductive anatomy is equally complex. Externally, the vulva consists of the labia majora, labia minora, clitoris, urethral opening, vaginal opening, and perineum. Internally, the vagina connects to the cervix (the entrance to the uterus), with the uterus positioned centrally in the pelvis. The fallopian tubes extend from either side of the uterus, with an ovary at each end.

Understanding these anatomical structures helps explain how sperm and eggs are produced, how fertilization occurs, and how pregnancy develops. The diagrams illustrate the relationship between different reproductive organs and their proximity to other body structures like the bladder, colon, and anus.

Study Tip: Creating your own labeled diagrams of these systems can significantly improve your understanding and retention of reproductive anatomy. Try drawing them from memory to test your knowledge!

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.

Where can I download the Knowunity app?

You can download the app in the Google Play Store and in the Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.9/5

App Store

4.8/5

Google Play

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user

Stefan S

iOS user

Samantha Klich

Android user

Anna

iOS user

Thomas R

iOS user

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

Elisha

iOS user

Paul T

iOS user

Biology

•

Dec 2, 2025

•

7 pages

Understanding the Reproductive System: Notes and Diagrams

andi :]

@snuggly_bunbun

Study Tip: Creating your own labeled diagrams of these systems can significantly improve your understanding and retention of reproductive anatomy. Try drawing them from memory to test your knowledge!