Video Transcript
How are spermatozoa different from
other male body cells? (A) They are the only cells that
are produced continuously throughout a male’s lifetime. (B) They are the only cells that
have 23 pairs of chromosomes in their nucleus. (C) They are the only cells that
are diploid and have a Y chromosome. (D) They are the only cells that
are haploid and have a flagellum. (E) They are the only cells that
are motile and undifferentiated.
Spermatozoa, or mature sperm cells,
are the male reproductive cells. They are formed through a process
called spermatogenesis and are differentiated with a specific function. Spermatozoa have a head that
contains a nucleus, a midpiece, and a tail or flagellum that gives them their
motility. Their nucleus is haploid, which
means they contain 23 chromosomes. 22 of these chromosomes are
autosomes, and one chromosome is a sex chromosome, which can be either X or Y.
Now let’s go through the different
choices to pick the best answer.
Answer (A) is incorrect because
spermatozoa are not the only cells produced continuously. There are other cells that are
produced throughout our lifetime, like red blood cells.
Answer (B) is incorrect because
they do not contain 23 pairs of chromosomes but 23 single chromosomes. They are haploid.
Answer (C) is incorrect because
spermatozoa are haploid and can have either an X or Y chromosome.
Answer (D) seems to be correct
because they are haploid and they do have a flagellum.
Let’s look at the last choice
before making our final decision. Answer (E) is incorrect because
there are other cells that are motile besides sperm, such as cells of the immune
system. Spermatozoa are also
differentiated.
Therefore, how spermatozoa are
different from other male body cells is given by answer choice (D). They are the only cells that are
haploid and have a flagellum.
