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67 Cards in this Set
- Front
- Back
The female gamete just before it is fertilized is termed |
a secondary oocyte |
|
The major body part(s) derived from ectoderm is/are |
1) the nervous system: sensory organs, lens of eye, tooth enamel, pituitary gland 2) skin: hair, nails, glands of the skin |
|
Teratogens are substances that |
cause birth defects |
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A normal oogonium is a(n) _______ cell |
diploid |
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The number of sperm cells in an ejaculate averages |
200 to 600 million |
|
the union of a sperm and egg is called a |
zygote |
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The stem cells from which sperm cells descend are called |
spermatogonia |
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The partial twinning that led to the births of conjoined twins Abby and Brittany Hensel must have happened during the first two weeks of gestation, because the girls |
share tissues that descend from ectoderm, endoderm, and mesoderm |
|
Cigarette smoking during pregnancy can cause |
spontaneous abortion, prematurity, low birth weight, and stillbirth |
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Which structures are part of the same primary germ layer? |
muscle, kidneys, dermis |
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After the second meiotic division, the number of chromosomes in each daughter cell is _______ that of the original parental cell. |
half |
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the placenta forms about __________ weeks after fertilization |
10 |
|
Body parts derived from endoderm include |
the urinary bladder epithelium, pancreas, and digestive tract lining |
|
Centenarians are |
people who live past 100 years |
|
Primary spermatocytes develop from the division of |
spermatogonia |
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Latika and Jeremiah are thrilled at the ultrasound scan that shows that their fetus appears to be a boy. It is the first time this has shown up on a scan. Latika is likely in her ___ week of pregnancy. |
twelth |
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The ovary of a newborn girl houses about ___ primary oocyte |
1,000,000 |
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The symptoms of fetal alcohol syndrome include |
impaired intellect |
|
The first step in oogenesis is |
an oogonium accumulates cytoplasm and DNA replicates |
|
The head of a sperm contains the |
DNA |
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__________ prepares sperm for penetration of the oocyte. |
Capacitation |
|
The critical period is |
the time during development when structures are sensitive to damage from a mutation, toxin, or virus |
|
Meiosis in females |
only completes if an oocyte is fertilized |
|
An embryo develops rudiments of all organs by week __ of prenatal development. |
8 |
|
During meiosis II in sperm development |
secondary spermatocytes divide meiotically to form haploid spermatids |
|
A bulbourethral gland secretes |
a mucus-like fluid |
|
mitochondria are found in which part of a sperm cell |
midpiece |
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Human prenatal development takes ___ weeks. |
38 |
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Connective tissues are part of the primordial embryo's |
mesoderm |
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After meiosis I, the number of chromosomes is _______ that of a somatic cell. |
half |
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The number of possible chromosome combinations in a human gamete, considering independent assortment but not crossing over, is about |
8 million |
|
The placenta |
nourishes the fetus and secretes hormones that maintain the pregnancy |
|
Body parts derived from endoderm include |
the urinary bladder epithelium, pancreas, and digestive tract lining |
|
Which is a characteristic of seminal fluid? |
It consists of sperm and secretions |
|
The hormone measured in a pregnancy test is |
hCG |
|
Sperm are produced within the |
seminiferous tubules |
|
which gland adds secretions to semen |
seminal vesicles |
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The tubular part of the uterus that extends downward into the upper vagina is the |
cervix |
|
Starvation in the uterus increases the risk in adulthood of developing |
heart and blood vessel disease, type 2 diabetes, and obesity |
|
The female gonads are the |
ovaries |
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Tanisha and Tawanda are twins but do not look at all alike. They are the result of fertilization of |
two oocytes by two sperm cells |
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A single-gene disease that can cause symptoms in a fetus is |
osteogenesis imperfecta |
|
A blastomere is a _____ and a blastocyst is _____. |
cell produced by cleavage; a hollow ball of cells |
|
The ovary in an adult contains |
many oocytes in various stages of maturity |
|
Erica is 8 years old, but looks as if she is 80. She is thin, with a beaked nose, very little hair, and several diseases that are typically seen in the elderly. She most likely has |
a segmented progeroid syndrome |
|
The number of sperm cells that form from a primary spermatocyte is |
4 |
|
Crossing over occurs during |
prophase I |
|
Fertilization usually occurs in the |
uterine tube |
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Monica takes the drug Accutane throughout her pregnancy, and her child has mental retardation and heart problems, due to the exposure. Accutane is a(n) |
teratogen |
|
Thalidomide is |
a drug that causes fetal limb defects, but is used to treat leprosy |
|
The reason that starvation during prenatal development raises the risk for cardiovascular and metabolic problems in adulthood is that |
metabolism in the fetus shifts to preserve vital organs, accelerating weight gain in childhood |
|
Synapsis occurs during |
prophase I |
|
During the first meiotic division |
homologous chromosome pairs separate |
|
Two oocytes released from the same ovary at the same time and fertilized by two sperm results in |
dizygotic twins |
|
Sperm undergo capacitation |
in the woman's body |
|
which gland adds fluid to semen which protects sperm cells from the acidic environment of the vagina |
bulbourethal gland |
|
Spermatocytes and oocytes are |
haploid |
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Blastocyst cells that give rise to the embryo's body constitute the |
inner cell mass |
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At the end of meiosis, the number of chromosomes in each daughter cell is halved because meiosis consists of |
two cell divisions, but one DNA replication |
|
The inner cell mass |
gives rise to the embryo |
|
The correct sequence for the steps of meiosis I is |
prophase-metaphase-anaphase-telophase |
|
By the end of meiosis I of oogenesis, an oogonium has become |
a secondary oocyte and a polar body |
|
Body parts derived from mesoderm are the |
muscle tissue, bone tissue, and internal reproductive organs |
|
The male and female reproductive systems of an adult each include |
gonads, tubes, gametes, hormones and secretions |
|
Amniotic fluid |
protects the embryo against jarring movements |
|
Meiosis is necessary because otherwise |
the fertilized ovum will have too much genetic material |
|
Amanda is eating a chicken breast, and wonders how many chromosomes are in each somatic cell of the unfortunate bird. She looks it up, 78. Therefore, a sperm or an unfertilized egg from a chicken would contain __ chromosomes. |
39 |