Genetics

A women who belongs to blood group A and is Rh positive has a daughter who is O positive and a son who is B negative. Rh positive is a simple dominant over Rh negative. Which of the following is a possible phenotype for the father? A)B positive. B) A negative. C)O positive D)O negative. E)A positive

A)B positive

In crossing a homozygous recessive with a heterozygote, what is the chance of getting an offspring with the homozygous recessive phenotype? A)25%. B)50%. C)100%. D)75%. E)0%

B)50%

Which of the following terms is LEAST related to the others? A)chronic villus sampling B)pedigree C)epistasis D)karyotype E)amniocentesis

C)epistasis

An achondroplastic dwarf man with normal vision marries a color blind woman of normal height. The man's father was 6 feet tall, and both of the women's parents were average height. Achondroplastic dwarfism is autosomal Dominic, and red and green color blindness is X linked recessive. How many of their female children might be expected to be color blind dwarfs? A) half. B)one out of four C)none. D) all E) three out of four

1C) none

This is caused by a dominant single gene defect and generally does not appear until the individual is 30-40 years of age. A)Huntington's disease B)Tay-Sach's disease C)Phenylketonuria D)Hemophilla E)Sickle-cell disease

A) Huntington's disease

If a human interface nucleus contains three Barr bodies, it can be assumed that the person: A) Is a female B)Has Turner syndrome C) Has four X chromosomes D)Is there male E)Has Down syndrome

A) Is a female

Albinism is caused by a recessive autosomal allele. A man and women, both normally pigmented, have an albino child together. For this trait, what is the genotype of the albino child? A) homozygous recessive B)heterozygous C)homozygous dominant D)hemizygous E)unknown, because not enough Information is provided

A) homozygous recessive

the probability that four coins will come up heads when flipped simultaneously is: A)1/16 B)1/8 C)1/2 D)1/4 E)1/64

A)1/16

A couple who are both carriers for the gene for cystic fibrosis have two children who have cystic fibrosis. What is the probability that their next child will be phenotypically normal? A)75%. B)0%. C)50%. D)100%. E)25%

A)75%

In a cross between parents who both exhibit the dominant curly and dark haired traits, one child has straight, light colored hair. What is the hair genotype of the parents? A)CcDdxCcDd B)CcddxCcDd C)CCddxccDd D)CCDDxCcDd E)CcDdxccdd

A)CcDdxCcDd

A sexually reproducing animal has two unlinked genes, on for head shape and one for tail length. It's genotype is HhTt. Which of the following genotypes is possible I a gamete from this organism? A)HT. B)tt. C)HhTt. D)Hh. E)T

A)Ht

Three babies were recently mixed up in a hospital. After consideration of the data below, which of the following represents the correct baby/parent combinations? couple# I II III blood groups A and A A and B B and O Baby # I II III blood groups B O AB A) I-2,II-3,III-1 B) I-2,II-1,III-3 C)I-3,II-2,III-1 D)I-1,II-3,III-2 E)I-3,II-1,II-2

A)I-2,II-3,III-1

The particular position of a gene on a chromosome is known as a(n) A)locus B)map distance. C)allele. D)tetrad. E)chiasma

A)locus

If inheritance of a human trait is sex linked(on the X chromosome) and recessive any of the following could result except that: A) Females could be a mosaic of two cell types B) The trait could be more common in females than male C) All females might become homozygous for the trait D) The gene for the trait might need to take to a dominant allele E) Expression of a trait might "skip" a generation

B) The trait could be more common in females than males

What is a genetic cross called between an individual of unknown genotype and a homozygous recessive? A) a hybrid cross B) a test cross C) a self-cross D)a dihybrid cross. E) an F1 cross

B) a test cross

Which of the following statements is TRUE regarding genomic imprinting? A)it explains sex- linked inheritance in which the sex of the parent carrying the mutant allele determines whether male or female offspring will be affected B)It explains cases where the gender of the parent from whom an allele is inherited affects the expression of that allele C)it is greatest in females because of the larger maternal contribution of cytoplasm D)it may explain the transmission of Duchenne's muscular dystrophy E) it is found in x- inactivation in human females during early embryonic development

B)It explains cases where the gender of the parent from whom an allele is inherited affects the expression of that allele

People who have red hair usually have freckles. This can best be explained by : A)sex-influenced inheritance B)linkage C)reciprocal translocation D)nondisjunction E)independent assortment

B)linkage

One example is the ABO blood group system A)incomplete dominance B)multiple alleles C)pleiotropy D)epistasis E)penetrance

B)multiple alleles

An achondroplastic dwarf man with normal vision marries a color blind woman of normal height. The man's father was 6 feet tall, and both of the women's parents were average height. Achondroplastic dwarfism is autosomal Dominic, and red and green color blindness is X linked recessive. They have a daughter who is a dwarf with normal color vision. What is the probability that she is heterozygous for both genes? A)0.25. B)0.50. C)1. D)0.75. E)0

C) 1

Tallness(T) is dominant to dwarfness(t), while red(R) flower color is dominant to white(r). The heterozygous condition results in pink (Rr) flower color. A dwarf red snapdragon is crossed with a plant homozygous for tallness and white flowers. what are the genotype and phenotype of the F1 individuals? A)ttrr- dwarf and white B)TTRR- tall and red C)TtRr- tall and pink D)ttRr- dwarf and pink E)TtRr- tall and red

C) TtRr- tall and pink

In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A lethal recessive allele that causes death of the emryo occurs on the Z chromosome in pigeons. what would be the sex ratio in the offspring of a cross between a male heterozygous for the lethal allel and a normal female? A)1:2 male to female B)1:1 male to female C)2:1 male to female D)4:3 male to female E)3:1 male to female

C)2:1 male to female

A recessive allele on the X chromosome is responsible for Reading green color blindness in humans. I woman with normal vision whose father is colorblind Mary's a color blonde mail. What is the probability that this couple's son will be colorblind? A)0%. B)75%. C)50%. D)100%. E)25%

C)50%

Black fur in mice(B) is dominant to brown fur(b). Short tails(T) is dominant to long tails(t). What proportion of the progeny of the cross BbTtxBBtt will have black fur and long tails? A)9/16. B)3/16. C)8/16. D)6/16. E)1/16

C)8/16

Individuals affected by the recessive trait, wooly hair are indicated by an open square of circle. what is the genotype of individual D-3? A)ww only B)WW only C)Ww only D)ww or Ww E) WW or ww

C)Ww only

Which of these syndrome affects males only? A) Down syndrome B)Edward syndrome C)patau syndrome D)duchenne's muscular dystrophy E) Turner syndrome

D) duchenne's muscular dystrophy

An achondroplastic dwarf man with normal vision marries a color blind woman of normal height. The man's father was 6 feet tall, and both of the women's parents were average height. Achondroplastic dwarfism is autosomal Dominic, and red and green color blindness is X linked recessive. How many of their male children would be color blind in normal height? A)none. B)three out of four. C)all. D) half. E) one out of four

D) half

What was the most significant conclusion that Gregor Mendel drew from his research? A)there is considerable genetic variation in garden peas B)dominant genes occur more frequently then recessive ones C)genes are composed of DNA D)traits are inherited in discrete units, one from each parent E) an organism that is homozygous for many recessive traits is at a disadvantage

D) traits are inherited in discrete units, one from each parent

Individuals affected by the recessive trait, wooly hair are indicated by an open square of circle. what is the genotype of individual B-5? A)WW or ww B)WW only C)Ww only D)ww only E)ww or Ww

D) ww only

Albinism is caused by a recessive autosomal allele. A man and women, both normally pigmented, have an albino child together. The couple decides to have a second child. What is the probability that this child will be albino? A)3/4 B)0 C)1/2 D)1/4 E)1

D)1/4

A couple who are both carriers for the gene for cystic fibrosis have two children who have have cystic fibrosis. What is the probability that their next child will have cystic fibrosis? A)50%. B)75%. C)100%. D)25%. E)0%

D)25%

A women and her husband both show the normal phenotype for pigmentation, but both had one parent who was an albino. Albinism is an autosomal recessive trait. If their first two children have normal pigmentation, what is the chance that their third child will be an albino? A)0%. B) 75%. C) 50%. D)25%. E) 100%

D)25%

A women and her husband both show the normal phenotype for pigmentation, but both had one parent who was an albino. Albinism is an autosomal recessive trait. What is the probability that their first child will be an albino? A)0%. B)50% C)100%. D)25%. E)75%

D)25%

A women and her husband both show the normal phenotype for pigmentation, but both had one parent who was an albino. Albinism is an autosomal recessive trait. What is the chance that their fourth child will have a homozygous genotype? A)25%. B)100%. C)0%. D) 50%. E)75%

D)50%

a Women who belongs to blood group A and is Rh positive has a daughter who is O positive and a son who is B negative. Rh positive is a simple dominant over Rh negative. Which if the following is a possible genotype for the mother? A)I^Airr. B)I^AiRR. C)I^AI^ARR. D)I^AiRr. E)I^AI^ARr

D)I^AiRr

In cattle, roan coat color occurs in the heterozygous(Rr) offspring of red(RR) and white(rr) homozygotes. when two roan cattle are crossed, the phenotype of the progeny are found to be in the ratio of 1 red: 2 roan: 1 white. which of the following crosses could produces the highest percentage of roan cattle? A)roan x roan B)white x roan C)red x roan D)red x white E) all of the above crosses would give the same percentage of roan

D)red x white

Which of the following is an example of polygenic inheritance? A) the ABO blood groups in humans B)sex-linkage in humans C)pink flowers in snapdragons D)skin pigmentation in humans E)white and purple color in sweet peas

D)skin pigmentation in humans

A man who carries an X linked allele will pass it on to: A) Half of his daughters B) All of his sons C) All of his children D) Half of his sons E) All of his daughters

E) All of his daughters

roan color is the result of absence of the dominance between red and white color genes. How would one produce a herd of pure-breeding roan- colored cattle? A)cross roan with roan B)cross red with white C)cross roan with red D)cross roan with red E)it cannot be done

E) it cannot be done

Individuals affected by the recessive trait, wooly hair are indicated by an open square of circle. what is the probability that individual C-1 is Ww? A)1/4 B)3/4 C)2/3 D)2/4 E)1

E)1

A couple has three children, all whom have brown eyes and blonde hair. Both parents are homozygous for brown eyes(BB), but one is a blond(rr) and the other is a red head(Rr). What is the probability that their next child will be a brown-eyed redhead? A)1. B)1/4. C)1/16. D)1/8. E)1/2

E)1/2

In a cross AaBbCcxAaBbCc, what is the probability of producing the genotype AABBCC? A)1/16 B)1/32 C)1/8 D)1/4 E)1/64

E)1/64

In snapdragons, heterozygotes have pink flowers, whereas the two homozygotes have red flowers or white flowers. When plants with red flowers are crossed with plants with white flowers, what proportion of the offspring will have pink flower? A)75%. B)25% C)50%. D)0%. E)100%

E)100%

Albinism is caused by a recessive autosomal allele. A man and women, both normally pigmented, have an albino child together. The mother is now pregnant for the third time, and her doctor tells her she is carrying fraternal twins. What is the probability that both children will have normal pigmentation? A)16/16 B)3/4 C)1/16 D)1/4 E)9/16

E)9/16

The finding that defective genes behave differently in offspring depending on whether they belong to the maternal or paternal chromosomes is implicated in which of the following: A) Prader-Willi syndrome B) Fragile X syndrome C) Angelman syndrome D) Only A and C are correct E)A,B,and C are correct

E)A,B,and C are correct

A women who belongs to blood group A and is Rh positive has a daughter who is O positive and a son who is B negative. Rh positive is a simple dominant over Rh negative. Which of the following is a possible genotype for the son? A)I^BI^Brr. B)I^BI^BRR. C)I^BiRr. D)I^BI^BRr. E)I^Birr

E)I^Birr

Substitution of the "wrong" amino acid in the hemoglobin protein results in this disorder. A)Huntington's disease B)Tay-Sach's disease C)Phenylketonuria D)Hemophilla E)Sickle-cell disease

E)Sickle-cell disease

A mammalian zygote with which of the following chromosomal abnormalities will never develop into a viable embryo? A) XXXY. B) XXX. C) XXY. D)XO. E)YO

E)YO