Spermiogenesis is the process where spermatids (round cells) change their shape into mature sperms (spermatozoa). Spermiation is the next step, where these sperms are released from the seminiferous tubules. Memory hook: spermiOGENESIS = "genesis" means to FORM the sperm; spermiATION = "action" of RELEASING the sperm.
Spermiogenesis forms the sperm from a spermatid; spermiation then releases the formed sperm FROM the seminiferous tubule into its cavity. The NEET trap is the word "into" instead of "from".
Your doubts, answered
Is spermiogenesis before or after spermiation?
Spermiogenesis comes FIRST. The spermatids first transform into sperms (spermiogenesis). Only after the sperm is fully formed can it be released. That release is spermiation, so spermiation comes second.
Does spermiation release sperm INTO or FROM the seminiferous tubules?
FROM. This is the most common NEET trap. The sperm heads are first embedded in Sertoli cells. In spermiation, the sperms are released FROM the seminiferous tubules into the cavity (lumen). If a statement says 'released into the tubules', it is WRONG.
Are sperms formed in spermiogenesis or in spermiation?
Sperms (spermatozoa) are FORMED in spermiogenesis, when spermatids change shape. In spermiation, no new sperm is made; the already-formed sperm is only released. NEET 2018 tested this exact point.
What is the difference between spermatogenesis, spermiogenesis and spermiation?
Spermatogenesis is the WHOLE process: spermatogonia to sperms. Spermiogenesis is only the LAST step inside it, where spermatids become sperms. Spermiation is the final release of those sperms from the tubules. So spermiogenesis and spermiation are two stages inside spermatogenesis.
What happens to spermatids during spermiogenesis?
Spermatids are round, non-motile haploid cells. During spermiogenesis they are transformed into spermatozoa: the nucleus condenses, the acrosome and tail form, extra cytoplasm is lost, and the cell becomes a streamlined motile sperm. No cell division happens here, only a change of shape.
Do Sertoli cells release the sperm in spermiation?
Yes. The sperm heads stay embedded in Sertoli cells during formation. In spermiation, these sperms are released from the Sertoli cells into the cavity of the seminiferous tubules. This is why NEET often links spermiation with Sertoli cells.
⚠️ The NEET trap ✗ Spermiation is the release of sperms INTO the seminiferous tubules, and spermiogenesis forms sperms from spermatogonia. ✓ Spermiation is the release of sperms FROM the seminiferous tubules (out of Sertoli cells into the lumen), and spermiogenesis is the transformation of spermatids (not spermatogonia) into spermatozoa. 🧠 NEET 2022 made BOTH statements wrong using the words 'into' and 'spermatogonia'. Sperm is released FROM the tubule, and spermiogenesis starts from spermatids, not spermatogonia.
Real NEET questions
NEET 2018
The difference between spermiogenesis and spermiation is
A · In spermiogenesis spermatozoa from sertoli cells are released into the cavity of seminiferous tubules, while in spermiation spermatozoa are formed.
B · In spermiogenesis spermatozoa are formed, while in spermiation spermatids are formed.
C · In spermiogenesis spermatids are formed, while in spermiation spermatozoa are formed.
D · In spermiogenesis spermatozoa are formed, while in spermiation spermatozoa are released from sertoli cells into the cavity of seminiferous tubules. ✓
Solution: NCERT defines spermiogenesis as the transformation of spermatids into spermatozoa (sperms), and spermiation as the release of those sperms, whose heads were embedded in Sertoli cells, from the seminiferous tubules. So in spermiogenesis sperms are FORMED, and in spermiation sperms are RELEASED. Option D is correct.
NEET 2022
Statement I: The release of sperms into the seminiferous tubules is called spermiation. Statement II: Spermiogenesis is the process of formation of sperms from spermatogonia. In the light of the above statements, choose the most appropriate answer.
A · Both Statement I and Statement II are correct
B · Both Statement I and Statement II are incorrect ✓
C · Statement I is correct but Statement II is incorrect
D · Statement I is incorrect but Statement II is correct
Solution: Statement I is wrong: spermiation releases sperms FROM the seminiferous tubules, not INTO them. Statement II is wrong: spermiogenesis is the transformation of spermatids into spermatozoa, not the formation of sperms from spermatogonia. Both statements are incorrect, so the answer is B.
Solved Human Reproduction NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
No. Spermiogenesis is only a change of shape (differentiation), not a division. The haploid spermatid simply transforms into a motile sperm. The divisions (mitosis and meiosis) happen earlier in spermatogenesis.
Where are the sperm heads embedded before spermiation?
The developing sperm heads are embedded in the Sertoli cells (nurse cells) of the seminiferous tubules. Sertoli cells provide nutrition and support. During spermiation they release the sperms into the tubule cavity.
Which hormone helps spermiogenesis in NEET?
FSH acts on the Sertoli cells, which then secrete factors that help spermiogenesis. This appears in NEET questions on hormonal control, so remember: FSH to Sertoli cells to spermiogenesis.
Are spermatids haploid or diploid?
Spermatids are haploid (23 chromosomes). They are produced when secondary spermatocytes complete the second meiotic division. These haploid spermatids then undergo spermiogenesis to become sperms.
What is the one-line NEET difference?
Spermiogenesis = spermatids FORM into sperms. Spermiation = formed sperms are RELEASED from the tubules. Formation first, release next.
