Deck 37: A: Genetics and Heredity

Question 1

Both males and females have an X chromosome.

Answer 1

True

Question 2

The X chromosome and the Y chromosome are the same size.

Answer 2

False

Question 3

In the human,the 22 pairs of autosomes always appear to be nearly identical to each other.

Answer 3

True

Question 4

Crossing over is a unique phenomenon that prevents genetic variation among offspring of a single set of parents.

Question 5

Sickle cell inheritance is a good example of how codominance works.

Question 6

The X chromosome contains few genes other than those that determine female sexual characteristics.

Question 7

A sperm containing a Y chromosome swims faster than a sperm containing an X chromosome.

Question 8

Gene linkage decreases the likelihood of genetic variation among the offspring of a single set of parents.

Question 9

A person who is heterozygous for albinism will have the abnormal phenotype for the condition.

Question 10

Every cell in the human body,both male and female,contains 46 chromosomes.

Question 11

Each offspring from a single set of parents is likely to be genetically unique.

Question 12

The manner in which the genotype is expressed is called the phenotype.

Question 13

Gregor Mendel proved that "independent units" are responsible for the inheritance of biological traits.

Question 14

Disease genes never provide biological advantages for human populations,regardless of the circumstances.

Question 15

Theoretically,the best chance for producing a girl infant would be for insemination to occur on the day of ovulation.

Question 16

Exons are removed from transcribed RNA to form the functional mRNA strand.

Question 17

Genetic mutations are always harmful.

Question 18

The Y chromosome is larger than the X chromosome.

Question 19

DNA molecules are segments of a gene.

Question 20

The principle of independent assortment states that each gamete formed is likely to have the same set of 23 chromosomes.

Question 21

Nondisjunction results in gametes that produce either trisomy or monosomy in the cells of offspring.

Question 22

Cystic fibrosis commonly occurs among all ethnic groups.

Question 23

Red-green color blindness,which involves a deficiency of photopigments in the retina,is an example of a recessive X-linked condition.

Question 24

A pedigree is a chart that illustrates genetic relationships in a family over several generations.

Question 25

Thalassemia is an example of a chromosomal abnormality involving trisomy of the 23rd chromosome.

Question 26

Osteogenesis imperfecta is a dominant genetic disorder of connective tissue.

Question 27

Phenylketonuria is caused by dominant genes that fail to produce the enzyme phenylalanine hydroxylase.

Question 28

Tay-Sachs disease is a dominant condition involving failure to make a lipid-producing enzyme.

Question 29

A genetic carrier is someone who has the gene but does not express the trait.An example would be someone who is heterozygous for a dominant/recessive trait.

Question 30

After age 35,a mother's chances of producing a trisomic child increase dramatically.

Question 31

Chorionic villus sampling is a newer procedure than amniocentesis.

Question 32

Fortunately,individuals with Klinefelter syndrome generally are not sterile.

Question 33

Mitochondrial inheritance is known to transmit genes for several degenerative nerve and muscle disorders.

Question 34

Genetic diseases may be caused by abnormality in a single gene or by a chromosomal defect.

Question 35

Osteogenesis imperfecta is a recessive disorder of connective tissues.

Question 36

One hypothesis regarding cancer involves the presence of oncogenes that,under normal conditions,regulate cell division so that it proceeds normally.

Question 37

Nondisjunction results in gametes that produce trisomy but not monosomy in the cells of offspring.

Question 38

The genotype XXY results in Turner syndrome.

Question 39

Some disease conditions,such as trisomy,always require the combined effects of inheritance and environmental factors.

Question 40

All congenital disorders are inherited disorders.

Question 41

Fetal tissue can be collected by amniocentesis,a procedure in which fetal cells floating in the amniotic fluid are collected with a syringe.

Question 42

Gene replacement therapy attempts to add genetically altered cells to the body.

Question 43

Crossing over increases genetic variation by forming new linkage patterns.

Question 44

All female gametes carry the X chromosome.

Question 45

Many of the polypeptides formed by encoded genes are enzymes that control and regulate chemical reactions in the cell.

Question 46

People with sickle-cell trait must be heterozygous.

Question 47

People who inherit the gene for hemophilia have an increased risk factor for a blood clotting disease that will express itself in the correct environmental conditions.

Question 48

Because there have been tragic setbacks is some gene therapy clinical trials,there are presently no approved gene therapies available.

Question 49

An ideogram and a pedigree show almost the same information.

Question 50

The sickle-cell gene produces an abnormal protein chain in the hemoglobin molecule.

Question 51

The inheritance of a genetic risk factor is not sufficient to cause a disease.

Question 52

The Genome Project discovered that the human genome contains about 30,000 genes,about three times the number that was expected.

Question 53

The process of mitosis in humans produces gametes that contain only 23 chromosomes.

Question 54

The proteome is to proteins in the cell what the genome is to the DNA in the cell.

Question 55

The ultimate goal behind gene augmentation is to change existing body cells.

Question 56

Genomics is the science of the analysis of the genome's code.

Question 57

A color-blind woman must have had a color-blind father.

Question 58

A karyotype is a grid used to determine the mathematical probability of inheriting genetic traits.

Question 59

Because of our greater complexity,the human genome carries about eight times as many genes as the fruit fly does.

Question 60

If PKU victims avoid large amounts of phenylalanine in their diets,especially during critical stages of development,severe complications can be avoided.

Question 61

Genes are segments of DNA molecules.

Question 62

Polygenic traits have more than one gene pair that contributes to their expression.

Question 63

Pseudogenes are gene fragments that can be reassembled to form a variety of polypeptides.

Question 64

A person with heterozygous sex chromosomes is a female.

Question 65

In a dominant/recessive trait,the heterozygous person would look like the homozygous person.

Question 66

Chromatin and chromosomes are both forms of DNA.

Question 67

A Punnett square or a pedigree can only predict the probability or possibility of passing on a trait to an offspring.

Question 68

The function of DNA is to transcribe the genetic code to tRNA.

Question 69

A Punnett square can be used to detect Down syndrome.

Question 70

One form of gene therapy uses bacteria-like DNA plasmids to carry therapeutic genes to a cell.

Question 71

Autosomes not only carry the same genes but also are carried in the same location on the chromosome.

Question 72

There are 44 autosomes in most human cells.

Question 73

The term pedigree refers to the entire collection of genetic material in each typical cell of the human body.

Question 74

A female who is red-green color blind must be heterozygous for the condition.

Question 75

A person who received a human-engineered chromosome as a form of gene therapy would have 47 chromosomes in that cell.

Question 76

Homozygous refers to a trait that is determined by a single gene pair.

Question 77

A strand of DNA wound around a histone is called a nucleosome.

Question 78

A disease carried on mDNA must be received from the mother.

Question 79

The term mutation simply means "change."

Question 80

For an individual to have Down syndrome,one of the gametes had to have contained 24 chromosomes.