Receptors for sperm binding in mammals are present on
Zona pellucida
Corona radiata
Vitelline membrane
Perivitelline space
The Correct Option is A
Solution and Explanation
To understand where the receptors for sperm binding are located in mammals, we need to consider the structure of the mammalian egg and the fertilization process.
In mammals, the egg is surrounded by several layers:
- Corona radiata: The outermost layer made up of follicular cells.
- Zona pellucida: A glycoprotein-rich layer beneath the corona radiata.
- Vitelline membrane: The innermost layer that directly surrounds the egg cell (also known as the oolemma in mammals).
The process of fertilization involves the binding of a sperm cell to the egg. This interaction primarily occurs at the zona pellucida.
The zona pellucida contains specific glycoproteins that act as receptors for the sperm. When a sperm cell approaches the oocyte, it first must penetrate the corona radiata. Then, it binds to the receptors on the zona pellucida, specifically engaging with the ZP3 glycoprotein, which facilitates sperm binding and triggers the acrosome reaction necessary for fertilization.
Given the options provided:
- Zona pellucida: Contains receptors necessary for sperm binding. Hence, this is the correct option.
- Corona radiata: Supports and protects the oocyte but is not directly involved in sperm binding.
- Vitelline membrane: Situated beneath the zona pellucida, not directly involved in the initial sperm binding.
- Perivitelline space: The space between the zona pellucida and the plasma membrane of the oocyte, also not involved in initial binding.
Therefore, the correct answer is zona pellucida as it is critical for sperm binding during fertilization.
Top Questions on Human health and disease
- What is antitoxin?
- UP Board XII - 2025
- Biology
- Human health and disease
Read the following passage and answer the questions that follow. Prevention is the frontline response to drug use. Effective interventions address the underlying conditions contributing to drug use, such as a lack of connection to family or community, instability, insecurity, trauma, mental health issues, etc. When addressed, these factors can effectively prevent the initiation of drug use and the progression to drug use disorders. Study the few key figures of drug use given below and answer the questions that follow.
(a) What do you infer from the figures in Table No. 1 about the people with drug use disorders, 2022 (in million)? State any two of your observations.
(b) How are Hepatitis C and HIV related to drug use disorders by people, as shown in Table No. 2? State the correlation between the two.
(c)
- [(i)] Give the scientific name of (p) shown in Table No. 1.
OR - [(ii)] Give the scientific name of (q) shown in Table No. 1.
- CBSE CLASS XII - 2025
- Biology
- Human health and disease
- [(i)] Give the scientific name of (p) shown in Table No. 1.
- Explain unique features of acquired immunity.
- Maharashtra Class XII - 2025
- Biology
- Human health and disease
- Which of the following is caused by unsterilized needle?
- Maharashtra Class XII - 2025
- Biology
- Human health and disease
- In the life cycle of a {Plasmodium, once the sporozoite enters the blood of the host, it invades the hepatic portal system, resulting in occurrence of change in the host body, leading to malaria
A. Sporozoite enters the hepatocytes and divides by schizogony leading to formation of cryptomerozoites
B. Inside RBCs, the micro-metacryptozoites become rounded and modify into a young trophozoites.
C. As the trophozoite grows in size, a central vacuole is developed so that the nucleus is pushed to one side into the peripheral cytoplasm, leading to amoeboid stage.
D. In Amoeboid stage the small red eosinophils granules appear in the cytoplasm of the host corpulses as Schuffner's granules}
Choose the most appropriate answer from the options given below:- CUET (PG) - 2025
- Zoology
- Human health and disease
Questions Asked in NEET exam
- Two identical point masses P and Q, suspended from two separate massless springs of spring constants \(k_1\) and \(k_2\), respectively, oscillate vertically. If their maximum velocities are the same, the ratio of the amplitude of P to the amplitude of Q is :
- NEET (UG) - 2025
- Waves and Oscillations
A sphere of radius R is cut from a larger solid sphere of radius 2R as shown in the figure. The ratio of the moment of inertia of the smaller sphere to that of the rest part of the sphere about the Y-axis is :
- NEET (UG) - 2025
- Moment Of Inertia
- A microscope has an objective of focal length \(f_o = 2\) cm and an eyepiece of focal length \(f_e = 4\) cm. The tube length of the microscope is \(L = 40\) cm. If the distance of distinct vision of eye is \(D = 25\) cm, the magnification in the microscope is:
- NEET (UG) - 2025
- Optical Instruments
AB is a part of an electrical circuit (see figure). The potential difference \(V_A - V_B\), at the instant when current \(i = 2\) A and is increasing at a rate of 1 amp/second is:
- NEET (UG) - 2025
- Electromagnetic Induction and Inductance
- Twins are born to a family that lives next door to you. The twins are a boy and a girl. Which of the following must be true?
- NEET (UG) - 2025
- Genetics
Concepts Used:
Male Reproductive System
The male reproductive system contains the external genitals (the penis, testes and the scrotum) and internal parts, including the prostate gland, vas deferens, and urethra. A man's fertility and sexual traits depend on the normal functioning of the male reproductive system, as well as hormones released from the brain.
Read More: Human Reproductive System
Organs and functions:
The male reproductive system is responsible for reproduction. It is made of the following parts:
Penis — the organ used for urination and sexual intercourse. It has spongy tissue which can fill with blood to cause an erection. It contains the urethra, which carries both urine and semen.
Scrotum — this is a loose bag of skin that hangs outside the body, behind the penis. It holds the testes in place.
Testes (or testicles) — these are a pair of egg-shaped glands that sit in the scrotum, on the outside of the body. They produce sperm and testosterone, which is the male sex hormone.
Epididymis — this is a highly coiled tube that lies at the back of the testes. All sperm from the testes must pass through the epididymis, where they mature and start to ‘swim’.
Vas deferens — this is a thick-walled tube joined to the epididymis. It carries sperm from the epididymis up to the prostate gland and urethra.
Prostate gland — this is a walnut-sized gland that sits in the middle of the pelvis. The urethra runs through the middle of it. It produces the fluid secretions that support and nourish the sperm.
Urethra — this is a tube that extends from the bladder to the external opening at the end of the penis. The urethra carries both urine and sperm.
Seminal vesicles — these are 2 small glands above the prostate gland that make up much of the fluid in semen.