Deck 21 (MC): Human Development and Genetics

Question 1

In the early embryo,the heart and skeletal muscles are derived from the:

A)ectoderm
B)mesoderm
C)endoderm
D)intraderm

Answer 1

B

Question 2

The early embryonic stage that is a solid sphere of cells is the:

A)morula,and the cells are all very similar
B)dermoblast,and the cells are all very similar
C)morula,and the cells are in three germ layers
D)dermoblast,and the cells are in three germ layers

Answer 2

A

Question 3

The portion of the blastocyst that secretes enzymes to permit implantation is the:

A)ectoderm
B)trophoblast
C)inner cell mass
D)endoderm

Answer 3

B

Question 4

In the early embryo,the liver and pancreas are derived from the:

A)ectoderm
B)mesoderm
C)endoderm
D)intraderm

Question 5

Which statement is NOT true of the events surrounding fertilization?

A)The sperm and egg each contribute 23 chromosomes.
B)Fertilization usually takes place in the fallopian tube.
C)The zygote begins to divide by meiosis to produce two cells,then four cells,and so on.
D)The hollow sphere of cells that is formed is called a blastocyst.

Question 6

In the gestation period,the period of embryonic growth lasts:

A)the first 8 weeks of gestation
B)the first 16 weeks of gestation
C)the last 8 weeks of gestation
D)the last 32 weeks of gestation

Question 7

In the early embryo,the ectoderm gives rise to the:

A)nerves
B)dermis and fat
C)lungs
D)bones

Question 8

The average gestation period lasts:

A)36 weeks
B)40 weeks
C)46 weeks
D)50 weeks

Question 9

The early embryonic stage that consists of a hollow sphere of cells with an inner cell mass is the:

A)morula
B)blastocyst
C)16-cell stage
D)chorion

Question 10

A zygote begins a series of cell divisions called:

A)differentiation,and the process is mitosis
B)cleavage,and the process is meiosis
C)differentiation,and the process is meiosis
D)cleavage,and the process is mitosis

Question 11

During gestation,at the end of the period of embryonic growth:

A)the cells have specialized into three germ layers
B)the first tissue has formed
C)many tissues have formed,but are not yet organized
D)all of the organ systems have been formed

Question 12

A human zygote contains how many chromosomes?

A)23
B)46
C)46 pairs
D)23 pairs plus two sex chromosomes

Question 13

The stem cells of a blastocyst are found in the:

A)inner cell mass
B)outer cell mass
C)trophoblast
D)All of these are stem cells.

Question 14

When a zygote undergoes cleavage,the process involved is:

A)mitosis
B)meiosis
C)implantation
D)fertilization

Question 15

An ectopic pregnancy is one in which:

A)fertilization is delayed
B)cleavage is very slow
C)the stem cells do not specialize as they should
D)the blastocyst becomes implanted outside the uterus

Question 16

Fertilization usually takes place in the:

A)vagina
B)uterus
C)fallopian tube
D)ovary

Question 17

The portion of the blastocyst that contains the potential embryo is the:

A)ectoderm
B)trophoblast
C)inner cell mass
D)endoderm

Question 18

Normal implantation of the blastocyst takes place in the:

A)endometrium
B)myometrium
C)serosa
D)fallopian tube

Question 19

In the gestation period,the period of fetal growth lasts:

A)the first 32 weeks of gestation
B)the first 20 weeks of gestation
C)the last 20 weeks of gestation
D)the last 32 weeks of gestation

Question 20

In the early embryo,the nervous system and epidermis are derived from the:

A)ectoderm
B)mesoderm
C)endoderm
D)intraderm

Question 21

Which of these embryonic structures is NOT paired with the correct primary germ layer from which it develops?

A)epidermis - ectoderm
B)liver - endoderm
C)heart - mesoderm
D)skeletal muscles - ectoderm

Question 22

The umbilical vein contains blood that has:

A)a high level of carbon dioxide and nutrients
B)a high level of oxygen and nutrients
C)a high level of oxygen and waste products
D)a high level of carbon dioxide and waste products

Question 23

For the embryo,the chorion:

A)contains fluid and absorbs shock
B)forms the first cells of the immune system
C)forms the fetal portion of the placenta
D)all of these

Question 24

The site of exchanges between maternal blood and fetal blood is the:

A)umbilical arteries
B)umbilical vein
C)placenta
D)myometrium

Question 25

For the embryo,the yolk sac:

A)provides a cushion
B)forms the first blood cells
C)provides nourishment
D)forms the fetal portion of the placenta

Question 26

The embryonic membrane that forms the fetal portion of the placenta is the:

A)chorion
B)amnion
C)yolk sac
D)umbilical cord

Question 27

In the placenta:

A)fetal blood moves into maternal circulation to pick up oxygen and nutrients
B)maternal blood moves into fetal circulation to deliver oxygen and nutrients
C)maternal red blood cells move into fetal circulation to deliver oxygen
D)oxygen is exchanged by diffusion from maternal blood vessels to fetal blood vessels

Question 28

Which statement is NOT true of the placenta and umbilical blood vessels?

A)Two umbilical arteries take blood to the fetus.
B)Maternal blood does not mix with fetal blood in the placenta.
C)The umbilical vein contains blood with a high level of oxygen.
D)In the placenta,exchanges take place by diffusion and active transport.

Question 29

Which of these embryonic structures is NOT paired with the correct primary germ layer from which it develops?

A)brain - ectoderm
B)kidneys - mesoderm
C)lungs - ectoderm
D)dermis - mesoderm

Question 30

The embryonic membrane that forms the first blood cells is the:

A)chorion
B)amnion
C)yolk sac
D)umbilical cord

Question 31

Blood is carried from the placenta to the fetus by the:

A)ductus venosus
B)umbilical vein
C)blood sinuses
D)umbilical arteries

Question 32

The umbilical arteries contain blood that has:

A)a high level of carbon dioxide and nutrients
B)a high level of oxygen and nutrients
C)a high level of oxygen and waste products
D)a high level of carbon dioxide and waste products

Question 33

In the early embryo,the mesoderm gives rise to the:

A)lens and cornea of the eye
B)skeletal muscles
C)lungs
D)liver

Question 34

Which statement is NOT true of the embryonic membranes?

A)The amnion contains fluid to cushion the embryo.
B)The chorion is the outermost area of the membranes.
C)The yolk sac will provide nourishment for the early embryo.
D)The yolk sac forms the first blood cells.

Question 35

The embryonic membrane that contains fluid to cushion the embryo is the:

A)chorion
B)amnion
C)yolk sac
D)umbilical cord

Question 36

In the early embryo,the endoderm gives rise to the:

A)nasal mucosa
B)bones
C)dermis
D)pancreas

Question 37

Blood is carried from the fetus to the placenta by the:

A)ductus arteriosus
B)umbilical vein
C)blood sinuses
D)umbilical arteries

Question 38

The placenta is formed by:

A)the maternal endometrium and fetal chorion
B)the maternal myometrium and fetal amnion
C)the maternal endometrium and fetal amnion
D)the maternal myometrium and fetal chorion

Question 39

For the embryo,the amnion:

A)contains fluid and is a cushion
B)provides oxygen and nutrients
C)forms the first blood cells
D)forms part of the placenta

Question 40

The embryonic membrane that has villi to provide nourishment for the early embryo is the:

A)chorion
B)amnion
C)yolk sac
D)umbilical cord

Question 41

The stage of labor during which the cervix begins to dilate is the:

A)first stage
B)second stage
C)third stage
D)fourth stage

Question 42

The stage of labor during which the infant is delivered is the:

A)first stage
B)second stage
C)third stage
D)fourth stage

Question 43

The genetic code in cells is the ___ of the ___.

A)DNA/ribosomes
B)RNA/chromosomes
C)RNA/nucleus
D)DNA/chromosomes

Question 44

The function of the hormone hCG is to:

A)inhibit the anterior pituitary gland
B)promote rapid growth of the embryo
C)stop the secretion of FSH and LH during pregnancy
D)stimulate the corpus luteum to secrete estrogen and progesterone

Question 45

The placental hormone that inhibits contractions of the myometrium during pregnancy is:

A)FSH
B)hCG
C)estrogen
D)progesterone

Question 46

A gene is the genetic code for:

A)one protein
B)one cell
C)one chromosome
D)one organ

Question 47

The stage of labor during which the amniotic sac ruptures is the:

A)first stage
B)second stage
C)third stage
D)fourth stage

Question 48

The placental hormones that prepare the mammary glands for lactation are:

A)progesterone and hCG
B)hCG and estrogen
C)estrogen and progesterone
D)progesterone and relaxin

Question 49

A gene is a specific part of ___,and is the genetic code for ___.

A)DNA/one chromosome
B)RNA/one protein
C)DNA/one protein
D)RNA/one chromosome

Question 50

After birth,the fetal ductus arteriosus ___ so that ___ blood will flow to the fetal lungs.

A)constricts/less
B)dilates/more
C)constricts/more
D)dilates/less

Question 51

A person has two genes for each genetic trait; these genes are called:

A)positive and negative
B)maternal and paternal
C)present and absent
D)dominant and recessive

Question 52

The placental hormones that inhibit ovulation during pregnancy are:

A)FSH and hCG
B)LH and progesterone
C)estrogen and hCG
D)estrogen and progesterone

Question 53

After birth,the infant's ductus venosus constricts because:

A)more blood is returning from the lungs
B)the umbilical arteries have been cut
C)more blood is flowing to the lungs
D)the umbilical vein has been cut

Question 54

The placental hormone that maintains the corpus luteum during early pregnancy is:

A)hCG
B)estrogen
C)FSH
D)progesterone

Question 55

The sex chromosomes in men are called:

A)XX
B)YY
C)XY
D)XZ

Question 56

After birth,the infant's pulmonary circulation is increased because the foramen ovale ___ and the ductus arteriosus ___.

A)is closed/constricts
B)is opened/constricts
C)is closed/dilates
D)is opened/dilates

Question 57

The stage of labor during which the placenta is delivered is the:

A)first stage
B)second stage
C)third stage
D)fourth stage

Question 58

After birth,the fetal foramen ovale is ___ in order to ___ pulmonary circulation.

A)closed/decrease
B)opened/increase
C)opened/decrease
D)closed/increase

Question 59

The hormone that causes strong contractions of the uterus during labor is:

A)oxytocin
B)estrogen
C)hCG
D)progesterone

Question 60

The sex chromosomes in women are called:

A)XX
B)YY
C)XY
D)XZ

Question 61

The autosomes a person has are:

A)all the chromosomes
B)the maternal or paternal set of chromosomes
C)the chromosomes other than the sex chromosomes
D)the dominant chromosomes

Question 62

Which statement is NOT true of human chromosomes?

A)The diploid number is 46.
B)Chromosome pairs number 2 and 13 are autosomes.
C)The sex chromosomes for women are XX.
D)A homologous pair is either maternal or paternal.

Question 63

The appearance or expression of a particular trait in a person is called the:

A)genotype
B)chromotype
C)phenotype
D)character type

Question 64

A pair of chromosomes that has maternal and paternal genes for the same traits is said to be a ___ pair.

A)heterozygous
B)homologous
C)homogeneous
D)heterogeneous

Question 65

A person's genotype for a particular trait refers to the:

A)genes that are present
B)genes that are absent
C)expression or appearance of the trait
D)possibility that the genes will be passed to children

Question 66

If a trait may appear in the phenotype only when two genes for it are present,that trait is called:

A)weak
B)recessive
C)binomial
D)expressive

Question 67

A person's phenotype for a particular trait refers to the:

A)genes that are present
B)genes that are absent
C)expression or appearance of the trait
D)possibility that the genes will be passed to children

Question 68

Homologous chromosomes are a pair of chromosomes that may also be called:

A)dominant and recessive
B)active and inactive
C)paired and unpaired
D)maternal and paternal

Question 69

A person's genetic makeup for a particular trait is called the:

A)genotype
B)chromotype
C)phenotype
D)character type

Question 70

A person who has two different genes for a particular trait is said to be:

A)homologous
B)homozygous
C)heterologous
D)heterozygous

Question 71

A person who has two similar genes for a particular trait is said to be:

A)homologous
B)homozygous
C)heterologous
D)heterozygous

Question 72

Which statement is NOT true of genes?

A)Heterozygous means that two different genes are present for a trait.
B)Homozygous means that two similar genes are present for a trait.
C)The genotype is the genes that are present.
D)The phenotype is the genes that are absent.

Question 73

In order for a recessive trait to appear in the phenotype:

A)no genes for it can be present
B)two genes for it must be present
C)one gene for it must be present
D)one or two genes for it must be present

Question 74

A homologous pair of chromosomes contains genes for:

A)the same traits
B)different traits
C)related traits
D)recessive traits

Question 75

For people,curly hair is dominant and straight hair is recessive.Genetics problem: Mom has straight hair and Dad is homozygous for curly hair.The chance that their child will have curly hair is:

A)0%
B)25%
C)50%
D)100%

Question 76

A person who is homozygous for a particular trait has:

A)only one gene (allele)
B)two similar genes (alleles)
C)an extra gene (allele)
D)two different genes (alleles)

Question 77

In order for a dominant trait to appear in the phenotype:

A)no genes for it must be present
B)two genes for it must be present
C)only one gene for it has to be present
D)None of these are true.

Question 78

If a trait may appear in the phenotype when only one gene for it is present,that trait is called:

A)dominant
B)strong
C)recessive
D)homozygous

Question 79

A human cell contains how many pairs of autosomes?

A)22 pairs
B)23 pairs
C)44 pairs
D)46 pairs

Question 80

A person who is heterozygous for a particular trait has:

A)an extra gene (allele)
B)two similar genes (alleles)
C)only one gene (allele)
D)two different genes (alleles)