Anatomy Of Male Urethra: Anatomy, Function, Conditions, Diagram

The male urethra measures about 18-20 cm long. It is a narrow muscular tube which helps in conducting urine and semen from the bladder and the ejaculatory duct, respectively. The urethra starts from the internal urethral orifice at the bladder to the urethral meatus at the tip of the glans penis. The urethra is composed of many segments, such as the prostatic, the membranous, and the spongy.

This Story also Contains

1. What is the Male Urethra?
2. Anatomy of the Male Urethra
3. Functions of the Male Urethra
4. MCQs on Anatomy of the Male Urethra
5. Recommended video on Anatomy of the Male Urethra

The doctors need to know the urethral anatomy, as urethral catheterisation is the most common medical procedure performed in healthcare. The male urethra is at risk of many pathological conditions. These conditions can lead to consequences such as renal failure and infertility. The anatomy of the male urethra is an important topic in the biology subject.

What is the Male Urethra?

The male urethra is a membranous structure extending from the bladder to the external opening at the tip of the penis. It serves to conduct the urine from the bladder and semen from the male reproductive system out of the body.

The male urethra forms a part of both the male reproductive and excretory systems. In functioning as the passageway through which semen and urine are voided, it thus serves the dual purpose of excretion and reproduction. It, therefore, becomes essential to learn about the anatomy and functioning of the male urethra for an in-depth understanding of male reproductive health.

Anatomy of the Male Urethra

The male urethra is about 18 to 20 cm in length, thus longer than the female urethra. It is divided into four main parts or segments: the prostatic urethra, the membranous urethra, the bulbar urethra and the penile urethra.

Prostatic Urethra

• The prostatic urethra is the very first part of the male urethra, and it passes through the prostate gland.

• It has a length of about 3 cm, and it receives secretion from the prostate gland and the ejaculatory duct.

Membranous Urethra

• The membranous urethra is the part that passes through the pelvic floor muscles.

• It is the smallest portion of the male urethra and is about 1 cm in length

Bulbar Urethra

• The bulbar urethra is a somewhat dilated portion that lies immediately distal to the membranous urethra.

• It is covered by the bulb of the penis and functions as a reservoir for both urine and seminal fluids

Penile Urethra

• The penile urethra is the longest portion, which traverses the entire length of the penis.

• At the end of the glans penis, it terminates at the external urethral orifice, allowing for the micturition and ejaculation.

Functions of the Male Urethra

The male urethra serves a dual purpose—expelling urine from the bladder and transporting semen during ejaculation. It plays a vital role in both the excretory and human reproductive systems.

• Excretion of Urine: The urethra primarily serves to conduct excretion of urine from the urinary bladder to the exterior.

• Semen Passage: During ejaculation, the urethra serves as a passage for the semen to pass through for its expulsion from the reproductive system.

• Dual Role: In the male urethra, the urinary and reproductive systems are combined and permit a dual role for the excretion of urine and semen.

MCQs on Anatomy of the Male Urethra

Q1. Urethral meatus refers to the:

Option 1: Urinogenital duct

Option 2: Opening of the vas deferens into the urethra

Option 3: The external opening of the urinogenital duct

Option 4: Muscles surrounding the urinogenital duct

Correct answer: 3)The external opening of the urinogenital duct.

Explanation:

The urinogenital duct's external opening is known as the urethral meatus.
Urine is expelled from the body through this hole. The urethral meatus is situated above the vaginal entrance in females and at the tip of the penis in males. When urinating, it acts as a conduit for urine to leave the body.

Hence, the correct answer is option 3)The external opening of the urinogenital duct.

Q2. Which is the widest part of the male urethra?

Option 1: Prostatic

Option 2: Bulbar

Option 3: Membranous

Option 4: Both a & c

Correct answer: 1) Prostatic

Explanation:

The male urethra is approximately 18-20 cm long. In addition to urine, the male urethra transports semen, a fluid containing spermatozoa and sex gland secretions.

The male urethra can be divided anatomically into three parts (proximal to distal) - prostatic, membranous and bulbar urethra.

Prostatic urethra:

• Begins as a continuation of the bladder neck and passes through the prostate gland.

• Receives the ejaculatory ducts (containing spermatozoa from the testes and seminal fluid from the seminal vesicle glands) and the prostatic ducts (containing alkaline fluid).

• It is the widest and most dilatable portion of the urethra.

Hence, the correct answer is option 1) Prostatic.

Q3. Which of the following statements is correct concerning the male urethra and external genitalia?

1. The female urethra is shorter than the male urethra.

2. Urine and semen pass through a common passage in males.

3. In human males, external genitalia is long and cylindrical.

4. Erectable tissues are yellow fibrous ligaments called the Corpora cavernosa.

Choose the correct option:

Option 1: Only 1

Option 2: 1,2, and 3

Option 3: All of the above

Option 4: None of the above

Correct answer: 3) All of the above.

Explanation:

Male urethra is shorter than in the females which provides a common pathway to both urine and semen. The penis is a male external genitalia. It is long and cylindrical. It consists of three types of erectile tissues. These tissues are made up of yellow fibrous ligaments and are called the Corpora cavernosa.

Hence, the correct answer is option 3) All of the above.

Recommended video on Anatomy of the Male Urethra