Genetics Chapter 4 CORRECT
identify the inheritance pattern based on the scenario: 1. The trait is expressed equally in both male and female 2. This trait appears in individuals who have unaffected parents 3. All children of affected parents are affected. 4. The risk of having an affected child when both parents are 5. unaffected heterozygote is 25%
Autosomal recessive
____ allele combinations cause offspring to die early in development. A) Epistatic B) Variably expressive C) Lethal D) Codominant
C) Lethal
Males are ____ for X-linked traits. A) homozygous B) heterozygous C) hemizygous D) pseudozygous
C) hemizygous
Human height is an example of a(n) ____ trait. A) autosomal B) sex-linked C) epistatic D) polygenic
D) polygenic
Inheritance of common recessive alleles can sometimes resemble dominant inheritance patterns in pedigree analyses.
True
Mitochondria evolved from free-living prokaryotes adapted to life inside primitive eukaryotes.
True
Recessive traits are only expressed in homozygous individuals.
True
T or F Duchenne muscular dystrophy and Becker's muscular dystrophy are caused by different mutations in the same X-linked gene.
True
A human male inherits X-linked traits from _____. A) his mother only B) his father only C) both his mother and father D) Males do not have X-linked traits
=A) his mother only
A female whose father was colorblind marries a normal male whose father was also colorblind. What is the probability that their daughter will be colorblind? A) 0% B) 25% C) 50% D) 75%
A) 0%
Each of the following statements describes Y-linked inheritance EXCEPT: A) Traits are transmitted from father to son B) There are no affected females C) Traits that involve infertility are not transmitted D) Traits are transmitted from mother to son
A) Traits are transmitted from father to son
Can a child have darker skin than either of his or her parents? A) Yes B) No C) No basis for determination
A) Yes
Which of the following is incorrect for an X-linked recessive trait? A) always expressed in the female B) passed from heterozygote or mother or homozygote mother to son C) expressed in a female homozygote D) affected female has an affected father and an affected or heterozygous
A) always expressed in the female
Which of the following is not an example of a multifactorial trait? A) cystic fibrosis B) skin color C) height D) fingerprint patterns
A) cystic fibrosis
Some people with polydactyly do not have any extra digits; some have an extra toe, while others have an extra finger. This situation is an example of a trait that is: A) incompletely penetrant. B) variably expressive. C) both a and b D) neither a nor b
A) incompletely penetrant. B) variably expressive. C) both a and b
Which of the following diseases is an example of a pleiotropic condition? select all that apply A)cystic fibrosis B)porphyria variegata C)Leber optic atrophy D)familial hypercholesterolemia
A)cystic fibrosis B)porphyria variegata
You are studying a degenerative condition that appears to be passed on only from the mother of the family. Affected fathers do not pass the trait to the offspring. This suggests that the trait might be _____. A)mitochondrial B)lethal C)epistatic D)incompletely dominant
A)mitochondrial
Suppose a woman with the mitochondrial disorder progressive external ophthalmoplegia has children with a man who does not have the condition. What are the chances that their children will have progressive external ophthalmoplegia? a. All of the girls but none of the boys will have progressive external ophthalmoplegia. b. None of the children will have progressive external ophthalmoplegia. c. All of the boys but none of the girls will have progressive external ophthalmoplegia. d. Fifty percent of the boys and fifty percent of the girls will have progressive external ophthalmoplegia. e. All of their children will have progressive external ophthalmoplegia.
All of their children will have progressive external ophthalmoplegia.
A trait more often present in both members of MZ twin pairs than in both DZ twin pairs has a large _____. A) environmental component B) inherited component C) random component D) No conclusions can be drawn in this case.
B) inherited component
A more informative way to assess the genetic component of a multifactorial trait is to study ____ who were separated at birth, then raised in very different environments. A) adopted children B) monozygotic (MZ) twins C) dizygotic (DZ) twins D) cousins
B) monozygotic (MZ) twins
Marfan Syndrome, a dominant single-gene defect, is characterized by lens dislocation, long limbs, spindly fingers, a caved-in chest, and a weakened aorta. This is an example of a(n) ____ trait. A) multifactorial B) pleiotropic C) incompletely dominant D) phenocopy
B) pleiotropic
Marfan Syndrome, a dominant single-gene defect, is characterized by lens dislocation, long limbs, spindly fingers, a caved-in chest, and a weakened aorta. This is an example of a(n) ____ trait. A)multifactorial B)pleiotropic C)incompletely dominant D)phenocopy
B)pleiotropic
A female whose father was colorblind marries a normal male whose father was also colorblind. What is the probability that their son will be colorblind? A) 0% B) 25% C) 50% D) 75%
C) 50% x-linked recessive pattern of inheritance Daughter of affected males are heterozygous carriers and unaffected sons of heterozygous female have a 50% change of inheriting the trait and being affected
Can a male be a carrier for a sex-linked disease? A) Yes, if the trait is recessive B) Yes, if the male's father and mother were carriers C) No, males have only a single copy of sex-linked genes D) No way to predict
C) No, males have only a single copy of sex-linked genes
If you examine a pedigree showing the transmission pattern of a mitochondrial gene mutation, which of the following statements would be false? A) Mothers pass the gene to all offspring. B) Fathers do not transmit the gene. C) Only females will express the trait. D) All of the above statements are true.
C) Only females will express the trait.
An affected male and a normal female had four children: two affected daughters and two normal sons. Each of the affected daughters ( and their normal husbands) produced affected sons and affected daughters. The couple's normal sons married normal women and had all normal children. What is the most likely mode of inheritance for this trait? A) autosomal dominant B) autosomal recessive C) X-linked dominant D) X-linked recessive
C) X-linked dominant
An affected male and a normal female had four children: two affected daughters and two normal sons. Each of the affected daughters ( and their normal husbands) produced affected sons and affected daughters. The couple's normal sons married normal women and had all normal children. What is the most likely mode of inheritance for this trait? A) autosomal dominant B) autosomal recessive C) X-linked dominant D) X-linked recessive
C) X-linked dominant
When a teratogen causes a birth defect that is similar to a genetic disorder, this is referred to as _____. A) genetic heterogeneity B) pleiotropy C) a phenocopy D) epistasis
C) a phenocopy
Multifactorial traits reflect _____. A) environmental influences only B) genetic influences only C) both environmental and genetic influences D) neither environmental nor genetic influences
C) both environmental and genetic influences
A human female inherits X-linked traits from _____. A) her mother only B) her father only C) both her mother and father D) Females do not have X-linked traits
C) both her mother and father
The term that is used to describe the severity or extent of a phenotype in an individual is called _____. A) pleiotropy B) penetrance C) expressivity D) epistasis
C) expressivity
Which of the following polygenic characteristics is probably a pure polygenic trait - one with no environmental input? A) skin color B) height C) eye color D) fingerprint patterns
C) eye color
A ____ is determined by more than one gene and varies continuously in expression. A) dominant allele B) population C) polygenic trait D) recessive allele
C) polygenic trait
____ allele combinations cause offspring to die early in development. A)Epistatic B)Variably expressive C)Lethal D)Codominant
C)Lethal
If you examine a pedigree showing the transmission pattern of a mitochondrial gene mutation, which of the following statements would be false? A)Mothers pass the gene to all offspring. B)Fathers do not transmit the gene. C)Only females will express the trait. D)All of the above statements are true.
C)Only females will express the trait.
When a teratogen causes a birth defect that is similar to a genetic disorder, this is referred to as _____. A)genetic heterogeneity B)pleiotropy C)a phenocopy D)epistasis
C)a phenocopy
Some people with polydactyly do not have any extra digits; some have an extra toe, while others have an extra finger. This situation is an example of a trait that is: A)incompletely penetrant. B)variably expressive. C)both a and b D)neither a nor b
C)both a and b
The term that is used to describe the severity or extent of a phenotype in an individual is called ____ A)pleiotropy B)penetrance C)expressivity D)epistasis
C)expressivity
What is the term that describe an allele that enter a family pedigree and produce pattern that resemble dominant inheritance
Common recessive alleles
X-linked dominant
Congenital Generalized Hypertrichosis is a type ------ inheritance
Genome-wide association studies _____. A) make use of SNP mapping B) relate sequence patterns to the probability of developing a particular disorder C) are more powerful than heritability studies D) All of the above are true in regard to association studies.
D) All of the above are true in regard to association studies.
An environmentally caused trait that appears to be inherited is called a(n) _____. A)pleiotropic gene B)penetrant gene C)expressed gene D)phenocopy
D) phenocopy
Each of the following statements describes Y-linked inheritance EXCEPT: A)Traits are transmitted from father to son. B)There are no affected females. C)Traits that involve infertility are not transmitted. D)Traits are transmitted from mother to son.
D)Traits are transmitted from mother to son.
Which of the following is a characteristic of an autosomal dominant trait? A)both males and females may be affected B)Most affected individuals are heterozygous C)successive generations are affected D)all of the above
D)all of the above
All of the following are features of mitochondrial DNA EXCEPT: A)mutates faster than DNA in the nucleus. B)maternal inheritance. C)no crossing over. D)one copy per mitochondrion.
D)one copy per mitochondrion.
The degree of phenotypic expression is known as?
Expressivity
All males are homozygous for Y-linked traits.
False
Huntington disease is an autosomal dominant condition; therefore, it is impossible for affected individuals to have unaffected offspring.
False
Males always pass an X chromosome to their sons and a Y chromosome to their daughters, while females pass an X chromosome to all of their offspring.
False
Males who are color-blind, a condition carried on the X chromosome, are always homozygous for this trait.
False
Mitochondrial genes are passed from the father to all of his children.
False
Penetrance and expressivity refer to genotypic variations in expression of inherited traits.
False
T or F A blood test cannot determine if a person is a carrier of Tay-Sachs disease because the mutant allele is undetectable.
False
T or F Most of those affected with an autosomal dominant genetic disorder are homozygous for that trait.
False
If the probability is less than %100, the trait shows?
Incomplete penetrance
The phenotype is not always observed amount individuals carrying the genotype
Incomplete penetrance
What does OMIM stand for?
Online Mendelian Inheritance in Man
Describe the probability that a disease phenotype will be present when the disease genotype is present
Penetrance
True
T or F: X-linked dominant inheritance males are often more severely affected typically associated with miscarriage or lethality in boys
A pedigree analysis is constructed for many reasons, including determining the risk of passing a certain genetic trait onto one's offspring.
True
Cystic fibrosis (CF) is a genetic disease that affects the viscosity of mucous in the lungs and digestive system, affecting not only the lungs, but also the pancreas, liver and intestines
True
True or False Y-linked traits are only expressed in males
True
T or F If a pedigree analysis suggests that an autosomal or X-linked inheritance pattern is equally likely, then additional genetic testing is needed to identify the pattern of inheritance.
Ture
A phenotype that varies in intensity for example: polydactyl two extra digits on hand and foot vs. one extra digit on foot
Variable expressivity
True
X-linked dominant traits are more common (over 850 identified) than X-linked dominant traits
True
X-linked dominant traits are passed from father to all his daughters but none of his sons.
Polydactyly is an autosomal dominant trait in which affected individuals have more than five fingers and/or toes. If a pedigree analysis indicates that an individual affected by polydactyly has two unaffected parents, then this suggests that polydactyly exhibits __ a. reduced penetrance b. reduced expressivity c. increased expressivity d. increased penetrance e. autosomal recessive inheritance
a. reduced penetrance
Consider a sex-linked recessive trait. Which of the following crosses would produce males and females with different phenotypes? A) homozygous normal female x normal male B) affected female x affected male C) affected female x normal male D) heterozygous normal female x affected male
affected female x normal male
If DNA testing reveals that Abraham Lincoln carried the gene for Marfan syndrome, ________. a. it would explain his short stature b. we will understand why he made certain decisions as U.S. President c. it would explain why only one of his children lived until adulthood d. his descendants who inherited the gene will either have, or be carriers of, Marfan syndrome e. it would explain why he did not survive the assassination
d. his descendants who inherited the gene will either have, or be carriers of, Marfan syndrome
Erythropoietic protoporphyria is an autosomal recessive condition, in which affected individuals have excessive cutaneous photosensitivity. This condition, however, sometimes exhibits a pseudodominant inheritance pattern, meaning that ________. a. the allele is X-linked b. this condition cannot be cured c. the allele is Y-linked d. the recessive allele is common e. the allele switches from recessive to dominant
d. the recessive allele is common
