26.3- Spermatogenesis occurs in the testes and produces mature sperm
Cytokinesis
cell division
how many sperm will eventually be produced from each primary spermatocyte ?
four haploid sperm will be produced from each diploid primary spermatocyte
spermatogenesis
sperm production; involves (1) mitosis and cell division (cytokinesis) (2) meiosis (3) spermiogenesis
structure of a sperm; the _____ is a flagellum, a whiplike organelle that moves the sperm
tail
spermiogenesis
the differentiation of immature male gametes into physically mature sperm
(T/F) the tail of the sperm is the only flagellum in the human body
T
define spermatogenesis
The production of sperm and involves mitosis, meiosis, and spermiogenesis
mitosis
-part of somatic cell division -producing two daughter cells each containing identical pairs of chromosomes
spermiogenesis (physical maturation); each spermatid matures into ____ sperm
1
paternal chromosome
a chromosome inherited from the father
meiosis
a special form of cell division involved in gamete production
structure of a sperm; the _________ is a membranous compartment containing enzymes essential to fertilization
acrosome
list the structures of a sperm
acrosome, head, neck, middle piece, tail (flagellum)
mitosis of spermatogonia; one of the daughter cells is a spermatogonium that remains in contact with the ________ membrane of the tubular
basement
haploid
contain only one member of each pair of chromosomes -ex. gametes produced from meiosis
diploid
containing two sets of chromosomes -ex. daughter cell
oocytes
female gametes
Meiosis II lasts a _____ hours
few
Meiosis II: the secondary spermatocytes soon enter meiosis II, which yields 4 _______ spermatids, each containing __ chromosomes
haploid, 23
structure of a sperm; the _____ is a flattened ellipse containing a nucleus with densely packed chromosomes
head
a ___________ ________ lacks an endoplasmic reticulum, Golgi apparatus, lysosomes, peroxisomes, inclusions, and many other intracellular structures
mature sperm
structure of a sperm; the ________ ____ contains mitochondria arranged in a spiral around the microtubules. _________ provide the ATP required to move the tail
middle piece, mitochondria
phases of spermatogenesis
mitosis, meiosis I, meiosis II, spermiogenesis (physical maturation)
structure of a sperm; the _______ contains both centrioles of the original spermatid. the microtubules of the distal centriole are continuous with those of the middle piece and tail
neck
mitosis of spermatogonia; the other daughter cell is a _________ ___________ that is displaced toward the lumen
primary spermatocyte
The events in the nucleus are the ______ for the formation of sperm or oocytes
same
Meiosis I: at the end of meiosis I, the daughter cells are called __________ _________
secondary spermatocytes
____ is a mobile carrier for the enclosed chromosomes
sperm
spermatogonia divide to produce sperm in a process called ___________
spermatogenesis
each mitotic division of a stem cell within the seminiferous tubules produces one daughter cell that remains a ______ cell and one daughter cell that enters _________
stem, meiosis
in __________, the corresponding maternal and paternal chromosomes come together
synapsis
a matched set of four chromatids is called a ________
tetrad
spermatogonia
the stem cells in the seminiferous tubules that divide to produce sperm in a process called spermatogenesis
mitosis of spermatogonia; the progression from spermatogonium to primary spermatocyte takes ___ days
16
mitosis of spermatogonia; each division of a diploid spermatogonium produces __ daughter cells
2
Meiosis I: each secondary spermatocyte contains ____ chromosomes, each with a pair of duplicate _______
23, chromatids
synapsis involves ___ pairs of chromosomes, and each member of each pair consists of two _______
23, chromatids
Meiosis I takes ___ days
24
spermiogenesis (physical maturation); this process from spermatids to sperm takes ___days
24
Meiosis II: for each primary spermatocyte that enters meiosis, _____ spermatids are produced
4
Meiosis (Meiosis I, Meiosis II) produces __ cells, each containing __ individual chromosomes
4, 23
the complete process of spermatogenesis occurs in ___ phases and takes ___ days
4, 64
Meiosis I: as meiosis begins, each primary spermatocyte contains ___ individual chromosomes
46
maternal chromosome
A chromosome inherited from the mother.
somatic cells (daughter cells) contain ____ pairs of chromosomes
23