Deck 36: A: Growth and Development

Question 1

The science of the development of the individual before birth is prenatology.

Answer 1

False

Question 2

Human cells contain a total of 23 chromosomes.

Answer 2

False

Question 3

The expulsion of seminal fluid from the male urethra into the female vagina is called insemination.

Answer 3

True

Question 4

The postnatal period begins at birth and ends when sexual maturity is attained.

Question 5

Once the zygote is formed,it immediately begins to cleave,and in about 3 days a solid mass of cells called a blastocyst is formed.

Question 6

Both spermatogonia and oogonia are diploid cells.

Question 7

A major function of amniotic fluid is to act as a shock absorber.

Question 8

In the human,the function of the yolk sac is to provide nutrients to the embryo.

Question 9

The placenta secretes human chorionic gonadotropin to reduce luteal secretion of estrogen and progesterone.

Question 10

The fertilized ovum,or zygote,is genetically complete.

Question 11

The prenatal period begins at conception and continues until the end of infancy.

Question 12

The daughter cells formed by meiotic division II contain a diploid number of chromosomes.

Question 13

Experiments have shown that the ovum actually attracts and "traps" sperm with special receptor molecules on the surface of the ovum.

Question 14

The chorion develops from the trophoblast to become an important fetal membrane in the placenta.

Question 15

During meiosis II,the phenomenon of "crossing over" occurs.

Question 16

The blastocyst is a solid mass of cells.

Question 17

The ovum lives for only about 24 hours.

Question 18

In both oogenesis and spermatogenesis,the cytoplasm is equally divided among the daughter cells.

Question 19

Meiotic division II is essentially the same as mitotic division I.

Question 20

Most of the primary oocytes develop to prophase I of meiosis before birth,and they stay at that stage until puberty.

Question 21

Cells of the embryonic disk differentiate into distinct types that form each of the three primary germ layers.

Question 22

The mesoderm forms the linings of various tracts,as well as several glands.

Question 23

Identical twins are not absolutely identical in terms of structure and function.

Question 24

Stage two of labor normally lasts from a few minutes to an hour.

Question 25

By day 35 of gestation,the heart of the embryo is beating.

Question 26

The brain and the spinal cord originate in the ectoderm.

Question 27

Alcohol can cross the placental barrier and cause injury to the developing fetus.

Question 28

In a normally developing fetus,maternal blood and fetal blood should never mix.

Question 29

The process by which the primary germ layers develop into many different kinds of tissues is called organogenesis.

Question 30

The placenta,a structural "anchor" and nutritive bridge,is also an excretory,respiratory,and endocrine organ.

Question 31

Stage two of labor is the period from the time of maximal cervical dilation until the expulsion of the placenta through the vagina.

Question 32

The placenta is composed of both maternal and embryonic tissue.

Question 33

In early pregnancy,hormones to sustain pregnancy are produced by the corpus luteum.

Question 34

Developmental biology is the name given to the branch of life science that studies the process of change over the life cycle.

Question 35

Human chorionic gonadotropin (hCG)secretion peaks about 16 weeks after fertilization and then drops to a continuous low level by about week 24.

Question 36

Stage two of labor is the period from the onset of uterine contractions until expulsion of the placenta through the vagina.

Question 37

Fraternal twins are always of two different sexes.

Question 38

By the second month of gestation,all organ systems of the embryo are formed and functioning.

Question 39

Pregnancy may produce pressure on the bladder,reducing the urine-storing capacity and resulting in frequent urination.

Question 40

Stage three of labor normally lasts from 12 to 36 hours.

Question 41

Fraternal twins result from the splitting of embryonic tissue from the same zygote early in development.

Question 42

Enzymes in the acrosome of the sperm are used to break down the zona pellucida of the egg.

Question 43

The decrease in progesterone levels accounts for the common symptoms of menopause.

Question 44

Because progesterone and estrogen are needed throughout pregnancy,the corpus luteum is maintained until the baby is born.

Question 45

Another name for a sex cell is a gamete.

Question 46

The neonatal period lasts from birth until 1 year.

Question 47

Degenerative heart and blood vessel disease is one of the most common and serious effects of aging.

Question 48

A woman is fertile for only about 24 hours during each reproductive cycle.

Question 49

The event that divides the prenatal and postnatal stages of development is birth.

Question 50

The average age-range of adolescence is from 13 to 19 years.

Question 51

Early in infancy,the baby has only one spinal curvature.

Question 52

In older adulthood,the bones develop indistinct and shaggy-appearing margins with spurs,a process called lipping.

Question 53

Progesterone therapy may be used to relieve some symptoms of menopause.

Question 54

Many of the developmental changes that occur during childhood are controlled by the secretion of sex hormones and are classified as secondary sex characteristics.

Question 55

It is possible for fraternal twins to have two different biological fathers.

Question 56

The morula is about three times the size of the zygote.

Question 57

The infant head is approximately one-fourth the total height of the body.

Question 58

Because the virus that causes German measles can cross the placenta,it has the potential to cause developmental defects in the fetus.

Question 59

A tubal pregnancy is an example of an ectopic pregnancy.

Question 60

Atherosclerosis results when fatty accumulations or other substances in blood vessels calcify.

Question 61

If an egg is not fertilized,the first polar body is not formed.

Question 62

Several thousand primary oocytes formed in the fetus do not survive to puberty.

Question 63

The full closure of skeletal growth plates does not occur until late childhood.

Question 64

Even though they are in the female,theca cells produce androgens.

Question 65

Adult stem cells can be found in the skin,nervous tissue,and muscle tissue.

Question 66

Scientists call the single cell of the zygote totipotent.

Question 67

The end products of both spermatogenesis and oogenesis are gametes.

Question 68

Only slightly more than 1% of the sperm deposited in the vagina reach the egg.

Question 69

Although there are several thousand primary follicles in the ovary,only one becomes a secondary follicle during each reproductive cycle.

Question 70

If an egg is not fertilized,the second polar bodies are not produced.

Question 71

Adult stem cells are called pluripotent.

Question 72

The goal of meiosis is to convert haploid cells to diploid cells.

Question 73

By age 14,all of the deciduous teeth have been lost.

Question 74

Fertility drugs that produce multiple births result in fraternal rather than identical siblings.

Question 75

One theory of aging proposes that a lack of ATP in the cell causes aging.

Question 76

The function of polar bodies is to reduce the number of chromosomes in the developing ova.

Question 77

After ovulation,the ovum first enters the infundibulum and moves toward the middle of the uterine tube where fertilization occurs.

Question 78

In mitosis,DNA replicates once.In meiosis,DNA replicates twice.

Question 79

As the blastocyst develops,the outer layer cell mass forms the amniotic cavity and the yolk sac.

Question 80

In most situations,stage II of labor is longer than stages I or III.