|
|
The gamete of a female has __________ chromosomes as(than) the gamete of
the male. |
|
the same number
of |
|
fewer |
|
more |
|
all of the above |
|
none of the above |
|
|
|
Which reproductive method is used most frequently by mammals? (27.1) |
|
fragmentation |
|
budding |
|
regeneration |
|
external fertilization |
|
internal fertilization |
|
|
|
A hermaphrodite is an animal that _____. |
|
fuses with one
of the opposite sex |
|
contains both
male and female reproductive systems in its body |
|
can create zygotes
of either sex |
|
reproduces only
asexually |
|
does all of the
above |
|
|
|
In general, what is the ploidy (n) state of human cells? |
|
diploid except
for gametes |
|
haploid except
for zygotes |
|
diploid early
in life, becoming haploid with age |
|
haploid early
in life, becoming diploid with age |
|
diploid in females;
haploid in males |
|
|
|
How does a zygote differ from an ovum? (27.1) |
|
A zygote has more
chromosomes. |
|
A zygote is smaller. |
|
A zygote consists
of more than one cell. |
|
A zygote is much
larger. |
|
A zygote divides
by meiosis. |
|
|
|
Suppose you wanted to get started in the animal-breeding business. You
could start out with only one of most of the following animals, but you would have to start with at least two _____. (27.1) |
|
sea anemones |
|
frogs |
|
tapeworms |
|
whiptail lizards |
|
sea stars |
|
|
|
External fertilization occurs mostly in _____. (27.1) |
|
land animals |
|
insects |
|
aquatic animals |
|
animals that reproduce
asexually |
|
mammals |
|
|
|
Bartholin's gland _____. |
|
contains spongy
tissue that fills with blood during arousal |
|
secretes progesterone
and estrogen to maintain pregnancy |
|
covers the vagina
before sexual intercourse |
|
secretes lubricating
fluid |
|
produces secretions
that contribute to semen |
|
|
|
Into which structure is a human oocyte released upon ovulation? (27.2) |
|
uterus |
|
oviduct |
|
ovary |
|
body cavity |
|
cervix |
|
|
|
How do ovulated oocytes get into the uterus? (27.2) |
|
Fimbriae sweep
over the oviduct. |
|
Cilia within
an oviduct create currents that sweep the egg toward the uterus. |
|
Since ovaries
are within the uterus, the ovulated egg is already within the uterus. |
|
Muscular projections
of the oviduct grasp the oocyte and force it into the uterus. |
|
The oocyte actively
swims through the oviduct, using its flagellum. |
|
|
|
On its way to fertilize a human egg, a sperm cell does not have to pass
through which of the following? (27.2) |
|
oviduct |
|
vagina |
|
ovary |
|
vas deferens |
|
cervix |
|
|
|
Which of the comparisons between oogenesis and spermatogenesis is NOT accurate?
(27.3) |
|
Follicle-stimulating
hormone promotes both egg and sperm development. |
|
Luteinizing hormone
triggers ovulation in females and androgen production in males. |
|
Releasing hormone
triggers the anterior pituitary to release FSH and LH in both males and females. |
|
Primary oocytes
and primary spermatocytes follow a similar pattern of development through meiosis. |
|
An ovum is not
produced in the absence of sperm, but sperm are produced regardless of what the ova are doing. |
|
|
|
In males, FSH _____. (27.3) |
|
is not produced;
it is a female hormone |
|
is directly responsible
for facial hair growth beginning at puberty |
|
is produced by
the hypothalamus |
|
stimulates the
production of sperm cells in the testes |
|
stimulates the
release of semen by the prostate gland during ejaculation |
|
|
|
The hormone that initiates the development of specialized cells in the
ovaries of women and triggers androgen production by the testes of men is _____. |
|
estrogen |
|
progesterone |
|
somatropin |
|
follicle-stimulating
hormone (FSH) |
|
luteinizing hormone
(LH) |
|
|
|
In humans, the testes are located outside the abdominal cavity within the
scrotum because _____. (27.3) |
|
the elevated
pressure within the abdominal cavity would collapse the small passageways within the testes |
|
this location
allows for a shorter pathway to the urethra |
|
blood flow to
the scrotum is not interrupted during erection |
|
sperm are unable
to mature properly at the higher temperatures found within the abdominal cavity |
|
all of the above |
|
|
|
Which part of the male reproductive tract warehouses sperm prior to their
exit from the male's body? (27.3) |
|
epididymis |
|
vas deferens |
|
glans |
|
urethra |
|
seminal vesicle |
|
|
|
What structure is part of both the excretory and reproductive systems in
males? (27.3) |
|
ureter |
|
urethra |
|
seminal vesicle |
|
urinary bladder |
|
vas deferens |
|
|
|
After being produced, human sperm continue their development in a structure
called the ____________. |
|
vas deferens |
|
epididymis |
|
seminal vesicle |
|
prostate gland |
|
bulbourethral
gland |
|
|
|
Where is one LEAST likely to find complete semen (in which all the components
are present)? |
|
in the vagina
of a woman who's trying to become pregnant |
|
in the epididymis |
|
at the junction
of the bulbourethral duct and the urethra |
|
at the tip of
the penis |
|
in the urethra |
|
|
|
Meiosis to produce the female egg cell is initiated in the _____. (27.4) |
|
ovary |
|
vagina |
|
uterus |
|
oviduct |
|
cervix |
|
|
|
From a single cell, oogenesis will produce ____________. (27.4) |
|
four ova (eggs) |
|
four spermatozoa |
|
an ovum and three
polar bodies |
|
a primary oocyte |
|
four polar bodies |
|
|
|
Assume 2n = 12 in a hypothetical species. In gametogenesis, the
number of chromosomes in a developing sperm cell would be __________ and in a first polar body would be __________. (27.4) |
|
6 ... 6 |
|
3 ... 3 |
|
6 ... 3 |
|
3 ... 6 |
|
none of the above |
|
|
|
In spermatogenesis, each primary spermatocyte gives rise to __________
sperm. (27.4) |
|
one |
|
two |
|
four |
|
eight |
|
millions of |
|
|
|
A large number of hormones function in the human menstrual cycle, but only
two of them are called female sex hormones. These are _____. (27.4)
|
|
follicle-stimulating
hormone and estrogen |
|
follicle-stimulating
hormone and progesterone |
|
follicle-stimulating
hormone and luteinizing hormone |
|
progesterone
and estrogen |
|
releasing hormone
and follicle-stimulating hormone |
|
|
|
Where do developing sperm cells undergo meiosis? (27.4) |
|
in the epididymis |
|
in the vas deferens |
|
in the seminal
vesicle |
|
in the seminiferous
tubules |
|
in the prostate
gland |
|
|
|
What does an ovum have that the sperm also has? (27.4) |
|
very little cytoplasm |
|
an external food
source |
|
a huge mitochondrion |
|
a haploid set
of chromosomes |
|
a sac full of
digestive enzymes |
|
|
|
At what point does the secondary oocyte complete meiosis? (27.4) |
|
when the luteinizing
hormone triggers ovulation |
|
after it is penetrated
by a sperm cell |
|
when the secondary
oocyte implants in the endometrium of the uterus |
|
when the egg
is fully surrounded by sperm and semen |
|
when acrosomal
enzymes begin to break down the egg's jelly coat |
|
|
|
The gamete of the female has __________ cytoplasm as(than) the male gamete.
(27.4) |
|
the same amount
of |
|
more |
|
less |
|
all of the above |
|
none of the above |
|
|
|
The amount of cytoplasm found in an egg is __________ that found in the
polar bodies. |
|
greater than |
|
equal to |
|
less than |
|
all of the above |
|
none of the above |
|
|
|
After ovulation occurs, the empty follicle _____. (27.5) |
|
can be recycled
to produce more eggs |
|
changes into
the corpus luteum and makes hormones |
|
quickly degenerates |
|
immediately initiates
menstruation |
|
becomes the site
of the implantation of a fertilized egg |
|
|
|
What is the source of the hormones that, when suddenly absent, are directly
responsible for the onset of menstruation? (27.5) |
|
hypothalamus |
|
pituitary |
|
ovarian follicle |
|
corpus luteum |
|
Bartholin's glands |
|
|
|
Which is a true statement about luteinizing hormone in the female reproductive
system? (27.5) |
|
It is produced
by the hypothalamus. |
|
It causes mitosis
of the primary oocyte. |
|
It inhibits ovulation. |
|
It triggers development
of endometrium in the corpus luteum. |
|
It is responsible
for mediating the production of estrogen and progesterone simultaneously. |
|
|
|
Which of the following hormones is the first to increase significantly
every 28 days or so, initiating the ovarian cycle? (27.5) |
|
progesterone |
|
follicle-stimulating
hormone |
|
estrogen |
|
luteinizing hormone |
|
human chorionic
gonadotropin |
|
|
|
The ovary undergoes several structural changes or events during the human
female's menstrual cycle. Which one of the following sequences is correct, beginning with the oocyte? (27.5) |
|
corpus luteum
development ... follicle development ... ovulation |
|
follicle development
... ovulation ... corpus luteum development |
|
corpus luteum
development ... ovulation ... follicle development |
|
follicle development
... corpus luteum development ... ovulation |
|
none of the above |
|
|
|
If a woman wants to become pregnant, what is the optimal day on which to
have sexual intercourse? (27.5) |
|
one week before
ovulation |
|
three days before
ovulation |
|
the day of ovulation |
|
the day before
menstruation is due to begin |
|
one week after
ovulation |
|
|
|
Birth control pills contain synthetic estrogen and progesterone. How might
these hormones prevent pregnancy? (27.5) |
|
They trigger
premature ovulation, before an egg is mature. |
|
They cause the
lining of the uterus to be sloughed off. |
|
They cause the
corpus luteum to degenerate. |
|
They keep the
pituitary from secreting FSH and LH, so ovulation does not occur. |
|
They prevent
the monthly development of the uterine lining. |
|
|
|
A peak in ______ triggers ovulation around the ______ day of the monthly
cycle. (27.5) |
|
progesterone
... 14th |
|
LH ... 7th |
|
FSH ... 2nd |
|
LH ... 14th |
|
estrogen ...
20th |
|
|
|
The plateau phase of human sexual response is characterized by _____. (27.6) |
|
increases in
breathing and heart rates |
|
the vaginal secretion
of lubricating fluids |
|
the relaxation
of muscles |
|
erection of the
penis and clitoris |
|
rhythmic contractions
of the reproductive structures |
|
|
|
PID _____. (27.7)
|
|
is caused as
the result of STDs caused by bacterial infections |
|
can cause sterility |
|
can cause pain |
|
can cause scarring |
|
all of the above |
|
|
|
The drug RU-486 was developed in France and is widely used in Europe as
a method of birth control. Its introduction to the United States has been controversial, however. The drug is taken after
sexual intercourse. It blocks implantation, and in this sense prevents pregnancy in a manner similar to _____. (27.8) |
|
the familiar
birth control pill used for the last 30 years |
|
spermicidal foam |
|
an intrauterine
device (IUD) |
|
tubal ligation |
|
a cervical cap |
|
|
|
Which one of the following is the LEAST effective method of birth control?
(27.8) |
|
vasectomy |
|
the pill |
|
IUD |
|
rhythm method |
|
condom |
|
|
|
A vasectomy is an effective technique for birth control in males because
it _____. (27.8) |
|
reduces the alkaline
secretions in the semen, and the sperm are then destroyed in the female reproductive tract |
|
causes the prostate
gland to enlarge and seal off the ejaculatory duct |
|
severs the capillaries
to the spermatozoa, which then die |
|
severs the capillaries
of the testes and prevents the arrival of pituitary hormone |
|
severs the route
used by the sperm to exit the male's body |
|
|
|
Which of the following most reduces the chances of both conception and
the spread of sexually transmitted diseases? (27.8) |
|
condom |
|
birth control
pill |
|
diaphragm |
|
intrauterine
device |
|
withdrawal |
|
|
|
After a sperm penetrates an egg, a fertilization envelope forms. This membrane
_____. (27.9) |
|
secretes important
hormones |
|
enables the fertilized
egg to implant itself in the wall of the uterus |
|
prevents more
than one sperm from entering the egg |
|
attracts additional
sperm to the egg |
|
is responsible
for the formation of the gastrula |
|
|
|
Sperm has several components; the function of the acrosome is to _____.
(27.9) |
|
produce base
to neutralize the acidic environment of the female reproductive system |
|
metabolize the
sugars provided by the semen for energy |
|
release an enzyme
that breaks down the membrane of the ovum |
|
propel the sperm
as they swim through the fluid of the female reproductive tract |
|
chemically identify
the proper oviduct |
|
|
|
Which part of the human sperm carries a haploid set of chromosomes? (27.9) |
|
head |
|
neck |
|
middle piece |
|
acrosome |
|
vitelline layer |
|
|
|
During cleavage the single large cell of the zygote is converted into a
_____. (27.10) |
|
multicellular
embryo consisting of smaller cells |
|
three-layered
embryo called a gastrula |
|
multicellular
embryo with a yolk plug and an archenteron |
|
multicellular
embryo consisting of a vitelline layer and a zygote |
|
fetus |
|
|
|
Cell divisions called __________ proceed so rapidly in the developing embryo
that there is no growth of the cells between divisions. (27.10)
|
|
meiosis |
|
binary fission |
|
cleavage |
|
fragmentation |
|
none of these |
|
|
|
One difference between the blastula and gastrula stages of development
is that _____. (27.10) |
|
blastula cells
are more differentiated than gastrula cells |
|
there are many
more cells in a blastula |
|
the blastula
consists of more cell layers |
|
the blastula
is a solid ball of cells, but the gastrula is hollow |
|
the gastrula
consists of three tissue layers |
|
|
|
Which one of the following describes the correct sequence of stages during
embryogenesis? (27.10) |
|
cleavage, blastula
formation, gastrulation |
|
cleavage, gastrulation,
blastula formation |
|
blastula formation,
gastrulation, cleavage |
|
blastula formation,
cleavage, gastrulation |
|
gastrulation,
cleavage, blastula formation |
|
|
|
Which of the following events is NOT part of gastrulation? (27.11) |
|
Cells migrate. |
|
The blastocoel
is obliterated. |
|
The archenteron
is formed. |
|
Cells are sorted
into three cell layers. |
|
Cells differentiate
into tissues. |
|
|
|
The three embryonic tissue layers—ectoderm, mesoderm, and endoderm—are
first present at the __________ stage. (27.11) |
|
neural fold |
|
nine-cell stage |
|
gastrula |
|
blastula |
|
four-cell stage |
|
|
|
During gastrulation, a(n) __________ forms. (27.11) |
|
eye |
|
simple digestive
cavity |
|
nervous system |
|
heart |
|
none of the above |
|
|
|
The nervous system is derived from _____. (27.12) |
|
ectoderm |
|
endoderm |
|
mesoderm |
|
both ectoderm
and mesoderm |
|
all three embryonic
tissue layers |
|
|
|
The skeleton and muscles form from the embryonic _____. (27.12) |
|
endoderm |
|
ectoderm |
|
mesoderm |
|
haploderm |
|
endoderm and
ectoderm |
|
|
|
What is the embryonic origin of the linings of the digestive tube and respiratory
systems? (27.12) |
|
endoderm |
|
ectoderm |
|
mesoderm |
|
both endoderm
and mesoderm |
|
all three embryonic
tissue layers |
|
|
|
All of the following structures are derived from mesoderm EXCEPT the _____.
(27.12) |
|
notochord |
|
pancreas |
|
heart |
|
dermis of skin |
|
muscles |
|
|
|
Someone may have webbed toes because _____. (27.13) |
|
of a failure
of gestation |
|
of a failure
of apoptosis |
|
of a failure
of pattern formation |
|
they are displaying
characteristics of humans' avian ancestry |
|
of a failure
of menstruation |
|
|
|
Cells relocated from the optic cup of an amphibian embryo to an abnormal
position result in the development of a lens at the graft location. This is an example of _____. (27.14) |
|
developmental
potential |
|
induction |
|
pattern formation |
|
apoptosis |
|
gastrulation |
|
|
|
Cell division by itself would only produce a formless heap of cells. Pattern
formation involves __________. (27.15) |
|
cellular differentiation |
|
differential
gene expression |
|
chemical signaling |
|
positional signals |
|
all of the above |
|
|
|
One early, and inexpensive, approach to infertility is to test a woman's
urine for a hormone that would indicate a high probability of ovulation. What hormone is this test kit designed to detect?
(27.16) |
|
oxytocin |
|
follicle-stimulating
hormone |
|
testosterone |
|
luteinizing hormone |
|
prolactin |
|
|
|
Pregnancy tests detect a hormone in a woman's urine that is present only
when an embryo is developing in her uterus. This hormone is secreted by _____. (27.16) |
|
the ovary |
|
the embryo |
|
a follicle |
|
the pituitary |
|
the endometrium |
|
|
|
This is the precise site of embryo implantation in a normal pregnancy.
(27.16) |
|
vagina |
|
cervix |
|
oviduct |
|
endometrium |
|
follicle |
|
|
|
Three or four of the following are correct descriptions of the functions
of the placenta. Which one, if any, is NOT a function of the placenta? (27.16) |
|
providing oxygen
to the fetus |
|
carrying wastes
from the fetus to the mother's circulatory system |
|
providing antibodies
to the fetus |
|
obtaining nutrients
from the mother's bloodstream |
|
All of the above
are functions of the placenta. |
|
|
|
If you wanted to examine the extraembryonic membranes surrounding a mouse
embryo, you would have to cut through which of the following to see all the others? (27.16) |
|
yolk sac |
|
amnion |
|
endoderm |
|
allantois |
|
chorion |
|
|
|
The allantois is an extraembryonic membrane that develops from the _____.
|
|
trophoblast cells |
|
yolk sac |
|
chorion |
|
amnion |
|
none of these |
|
|
|
Which one of the following embryonic membranes found in birds and reptiles
functions in waste disposal? (27.16) |
|
allantois |
|
amnion |
|
chorion |
|
fertilization
envelope |
|
yolk sac |
|
|
|
During the first trimester _____. (27.17) |
|
the mother may
feel movements, and fetal activity may be visible through the abdominal wall |
|
an ultrasound
can be performed to determine the gender of the fetus |
|
the fetus's eyes
are open |
|
the fetus is
most vulnerable to exposure to drugs and radiation |
|
the fetus weighs
about 3.5 kg |
|
|
|
The uterine contractions during labor are stimulated by _____. (27.18) |
|
estrogen and
progesterone |
|
oxytocin and
prostaglandins |
|
prolactin and
releasing hormone |
|
|
|
|
|
|
|
Which of these can cause female infertility? (27.19) |
|
scarring of the
reproductive tract, such as that caused by STDs |
|
failure to ovulate |
|
the production
of antibodies that react with sperm |
|
blockage of the
oviducts |
|
all of the above |
