Deck 42: Animal Development

Question 1

Human embryos differ from bird embryos in that:

A)bird embryos have an extra membrane, the allantois, that is not found in human embryos.
B)human embryos have no yolk sac.
C)human embryos have a yolk sac, but it contains no yolk.
D)human embryos do not develop into a primitive streak stage.
E)bird embryos develop a very different body structure than the adult.

Answer 1

C

Question 2

One characteristic of animal development is the specialization in both structure and function that cells undergo. This is called:

A)direct development.
B)placental development.
C)indirect development.
D)internal development.
E)differentiation.

Answer 2

E

Question 3

When a researcher transplanted the nucleus of an intestinal cell from a tadpole into an egg cell whose nucleus had been destroyed, the egg developed into a normal frog. This illustrates that:

A)each cell of an organism has all the genes needed for development.
B)the homeobox genes in a transplanted nucleus undergo mutation.
C)a nucleus that is removed from its normal location is influenced by adjoining cells.
D)scientists can clone a human by putting one of his or her nuclei into an egg cell.
E)genes are lost in differentiation.

Answer 3

A

Question 4

The cells that line the inside of the blastopore become the:

A)skin.
B)muscles.
C)nervous system.
D)skeleton.
E)digestive tract.

Question 5

Which of the following is the result of gastrulation?

A)a morula
B)a zygote
C)the formation of organs
D)a three-layered embryo
E)a blastula

Question 6

At the blastula stage, the embryo consists of:

A)a solid mass of cells, each the size of the zygote.
B)three differentiated layers of cells.
C)a hollow ball of cells.
D)cells that have different DNA content.
E)a cluster of cells that are much larger than normal cells.

Question 7

Which germ layer forms the pancreas?

A)endoderm
B)ectoderm
C)mesoderm
D)somite
E)amnion

Question 8

In placental organisms, the _______ is the fetal contribution to the placenta.

A)allantois
B)amnion
C)chorion
D)yolk sac
E)blastopore

Question 9

Which extraembryonic membrane lies immediately beneath the shell of a reptile embryo?

A)allantois
B)amnion
C)chorion
D)yolk sac
E)placenta

Question 10

During the embryonic stage, a hollow ball of cells is known as a:

A)morula.
B)blastula.
C)gastrula.
D)larva.
E)blastopore.

Question 11

________ is the developmental event that results in the formation of a primitive gut and the three tissue layers.

A)Blastulation
B)Metamorphosis
C)Gastrulation
D)Cleavage
E)Induction

Question 12

In a reptile egg, which membrane is analogous to a lung?

A)allantois
B)amnion
C)chorion
D)yolk sac
E)blastopore

Question 13

The nervous system forms from the:

A)ectoderm.
B)mesoderm.
C)endoderm.
D)yolk.
E)chorion.

Question 14

In a bird egg, the ________ provides the watery environment in which the embryo develops.

A)allantois
B)amnion
C)chorion
D)yolk sac
E)shell

Question 15

Birds hatch out of their eggs looking like small versions of the adult. This is an example of:

A)direct development.
B)genetic dwarfism.
C)indirect development.
D)internal development.
E)external development.

Question 16

Suppose a mutant fish embryo does not form an endoderm, yet the embryo continues to develop. Which of the following structures might the embryo lack?

A)skin
B)heart
C)nervous system
D)stomach
E)kidneys

Question 17

The embryo of the ________ undergoes direct development.

A)butterfly
B)lobster
C)frog
D)fly
E)bluebird

Question 18

The metamorphosis of a caterpillar into a butterfly is an example of:

A)direct development.
B)placental development.
C)indirect development.
D)internal development.
E)external development.

Question 19

If a cell divides by mitosis so that one cell eventually becomes part of the brain and the other cell becomes part of a salivary gland, the cells have:

A)lost genes.
B)increased their genetic variability.
C)diffused.
D)taken up genes from surrounding cells.
E)differentiated.

Question 20

What is differentiation?

A)the process in which different tissues specialize into specific organs
B)the process in which different cells develop into different cell types
C)the process in which different organs specialize in function
D)the process in which the embryo specializes into different sexual organs

Question 21

Transplanting embryonic eye tissue into the back of a developing tadpole will cause a lens to grow on the back of the tadpole. This is an example of:

A)metamorphosis.
B)programmed cell death.
C)induction.
D)cleavage.
E)gastrulation.

Question 22

If an embryo divides into three during the morula stage:

A)the embryos will die.
B)the embryos will develop severe birth defects due to missing genes.
C)normal identical triplets will be born.
D)three distinctly different embryos will develop, depending on which homeoboxes went with which cell group.
E)the embryos will develop, but they may be missing some organs based on which germ layers were transferred with each section.

Question 23

A developing human is considered an embryo after ________ weeks.

A)2
B)4
C)8
D)12
E)16

Question 24

Based on experiments with amphibian embryos, Spemann found that:

A)in most cases, transplanted cells assumed the developmental fate of the area to which they were transplanted.
B)transplanted cells always died.
C)transplanted cells always formed a whole new embryo.
D)cells maintained their original differentiation no matter where they were transplanted.
E)transplanted cells completely undifferentiated into random masses of tissue.

Question 25

Induction refers to:

A)the pushing in of cells to form the gastrula.
B)the formation of the nervous system.
C)substances from one embryonic cell influencing the development of other cells.
D)the formation of the mesoderm layer in a gastrula.
E)hormones from the mother's blood altering the development of the embryo.

Question 26

The structure produced by cleavage of a human zygote is called a(n):

A)chorion.
B)blastocyst.
C)blastopore.
D)embryonic disc.
E)gastrula.

Question 27

The birth defect spina bifida results in part of the spinal cord lying outside of the body. This defect is due to abnormal development of the:

A)neural tube.
B)gill grooves.
C)allantois.
D)placenta.
E)embryonic disc.

Question 28

A human embryo is known as a fetus after ________ weeks.

A)2
B)4
C)10
D)12
E)16

Question 29

In humans, implantation occurs:

A)just prior to fertilization.
B)immediately after fertilization.
C)when the embryo is a blastocyst.
D)when the embryo is a gastrula.
E)after the formation of the neural tube.

Question 30

At what stage does a human embryo implant in the uterus?

A)gastrula
B)embryonic disc
C)morula
D)blastocyst
E)fetal

Question 31

Cells differentiate during development because:

A)each cell contains only a portion of the genes.
B)genes respond only to influences outside the mother's body.
C)in each cell some genes are expressed and others are suppressed.
D)chemicals in the sperm cytoplasm determine which cells develop.

Question 32

The umbilical cord of a mammal connects the:

A)fetus and the placenta.
B)amnion and the chorion.
C)yolk sac and the allantois.
D)embryo and the amnion.
E)maternal and fetal bloodstreams.

Question 33

What makes the cells of a developing embryo differentiate into various types of cells?

A)They have different genes.
B)Different genes are activated.
C)The DNA of their mitochondria is different.
D)Once certain genes of a cell have caused it to differentiate, the other genes are lost.
E)Special genes in the cytoplasm cause this.

Question 34

At which stage is the human embryo most susceptible to damage?

A)just before birth
B)during cleavage
C)during organogenesis
D)during the fourth and fifth months
E)during the last trimester

Question 35

After induction occurs:

A)cells have different genes.
B)the fate of the cell is permanently fixed.
C)the DNA of the mitochondria differentiates into new genes.
D)transcription of all genes stops.

Question 36

The dorsal lip of the blastopore:

A)becomes the neural tube.
B)becomes the digestive tract.
C)induces the surrounding cells to differentiate.
D)forms the chorion.
E)lacks the genes necessary to develop the embryo.

Question 37

Your biceps muscle is derived from the:

A)endoderm.
B)ectoderm.
C)mesoderm.
D)blastopore.
E)amnion.

Question 38

In humans, fertilization occurs in the:

A)ovary.
B)testes.
C)uterine tube.
D)uterus.
E)vagina.

Question 39

The proteins that bind to the DNA near regions where gene transcription begins are called:

A)mRNA.
B)promoter genes.
C)the gray crescent.
D)homeobox genes.
E)transcription factors.

Question 40

During mammalian development:

A)a zygote becomes a blastula.
B)a gastrula becomes a morula.
C)a morula becomes a blastula.
D)a morula becomes gastrula.
E)a blastula becomes a zygote.

Question 41

________ is the medication given to combat morning sickness that caused deformed and missing limbs in infants.

A)Alcohol
B)Rubella
C)Accutane®
D)Thalidomide
E)Nicotine

Question 42

The sexually immature stage in indirect development is the larva. True or False?

Question 43

Stem cells developed by inserting genes into cells from an adult are ________ cells.

A)induced pluripotent stem
B)embryonic stem
C)chorionic villi
D)embryonic disc
E)gastrula

Question 44

Which portion of the blastula becomes the embryonic placenta?

A)chorion
B)embryonic disc
C)inner cell mass
D)primitive streak
E)yolk sac

Question 45

What is the main purpose of the last seven months of pregnancy?

A)formation of major organs
B)organization of organs into organ systems
C)formation of the brain
D)growth
E)formation of cell layers

Question 46

Most fetuses can survive outside the womb after a minimum of ________ weeks.

A)15
B)20
C)32
D)38
E)45

Question 47

Which of these hormones promotes the secretion of milk?

A)colostrum
B)oxytocin
C)progesterone
D)prolactin
E)estrogen

Question 48

The process through which a human embryo develops into an adult is called metamorphosis. True or False?

Question 49

Suppose a pregnant woman took a drug that causes incomplete brain formation during fetal development. When must the woman have taken the drug for this effect to occur?

A)in the first two months of development
B)between the third and fourth months of development
C)between the fifth and sixth months of development
D)between the seventh and eighth months of development
E)during labor

Question 50

The fetus can move and respond to stimuli as early as the ________ month.

A)second
B)third
C)fourth
D)fifth
E)sixth

Question 51

A human embryologist examines a 3-week-old embryo and notices that it has not developed a notochord. If the embryo survives, it will lack:

A)a brain and a spinal cord.
B)a heart and lungs.
C)skin and blood vessels.
D)a stomach and a pancreas.

Question 52

Free radicals are most damaging to the:

A)mitochondria.
B)cell membrane.
C)cytoplasm.
D)placenta.
E)bone.

Question 53

All the cells in an animal are genetically identical. True or False?

Question 54

The placental blood vessels:

A)mix maternal blood and fetal blood.
B)draw oxygen from the fetal blood and pass it to the mother.
C)allow for the exchange of wastes and nutrients but keep the maternal and fetal circulations separate.
D)manufacture hormones that slow the growth of the embryo, preventing it from outgrowing the uterus.
E)prevent all microbes and toxins from crossing from mother to child.

Question 55

The cells of an aging animal function less efficiently because:

A)their metabolic rate is very low.
B)they lose their organelles.
C)they cannot repair their DNA.
D)protein synthesis has stopped.
E)they cannot divide by mitosis.

Question 56

________ is the bacterial invader that causes stillbirths and mental retardation when it crosses the placenta and attacks the fetus.

A)HIV
B)Rubella
C)Syphilis
D)Thalidomide
E)Streptococcus

Question 57

________ diffuse(s)from fetal blood to maternal blood in the placenta.

A)Oxygen
B)Wastes
C)Alcohol
D)Infectious organisms
E)Nutrients

Question 58

In the placenta:

A)chorionic villi are bathed in pools of maternal blood.
B)fetal blood and maternal blood mix.
C)all substances in maternal blood that may be harmful to the fetus are prevented from going through.
D)the amnion and the chorion grow into the uterus wall.
E)hormones are absorbed to prevent them from influencing the developing fetus.

Question 59

In animals that undergo indirect development, the newborn look like smaller versions of the adults. True or False?

Question 60

Babies who are nursed rather than fed formula:

A)grow faster.
B)grow slower.
C)gain antibodies from the mother.
D)fail to develop an immune system.
E)are sicker than formula-fed babies.

Question 61

In blastulas, if cells from an area that would normally become skin are transplanted into an area that would become nervous system, the transplanted cells will become nervous system. True or False?

Question 62

At 10 weeks, the blastula becomes an embryo. True or False?

Question 63

The extraembryonic membrane that sends blood vessels into the endometrium is the chorion. True or False?

Question 64

In a morula, the cells are still undifferentiated. True or False?

Question 65

Yolk sacs are found only in animals with shelled eggs. True or False?

Question 66

The early divisions of the zygote are called cleavage. True or False?

Question 67

Homeobox genes determine the overall shape of the body and the location of its parts. True or False?

Question 68

Maternal blood and fetal blood are mixed in the placenta. True or False?

Question 69

The nervous system develops from the endoderm. True or False?

Question 70

All amphibians, reptiles, and mammals pass through embryonic stages in which they have tails and webbed fingers. True or False?

Question 71

In species with direct development, fewer offspring are produced, but a higher proportion survives to adulthood. True or False?

Question 72

Chorionic gonadotropin is secreted by the endometrium when a woman becomes pregnant. True or False?

Question 73

The most rapid differentiation in an embryo occurs during the first two months of pregnancy. True or False?

Question 74

The small hollow ball of cells in early development is the zygote. True or False?

Question 75

The amnion forms the watery environment that encloses the embryo. True or False?

Question 76

Cellular differentiation depends on which genes are expressed in the cell. True or False?

Question 77

The placenta prevents pathogenic microbes like HIV and chemicals like alcohol from reaching the baby's bloodstream. True or False?

Question 78

The blastopore forms during gastrulation. True or False?

Question 79

The blastocyst implants in the endometrium about 7 days after fertilization. True or False?

Question 80

The mesoderm develops into the gonads and the skeleton. True or False?