A & P 2: chapter 29
Situation in which an individual has different alleles making up the genotype for a particular trait. 1)heterozygous 2)autosomes 3)dominant 4)allele
Heterozygous
Which of the following exemplifies polygenic inheritance? 1)hemophilia 2)sickle-cell trait 3)height 4)red-green color blindness
height
Two alleles expressing exactly the same information for a trait are designated as _____ 1)heterozygous 2)hemizygous 3)monogamous 4)homozygous
homozygous
When alleles controlling a trait are the same, they are said to be _______ 1)dominant 2)recessive 3)heterozygous 4)homozygous
homozygous
An individual who is heterozygous for a particular trait, yet expresses both alleles of that trait, is an example of ________. 1)dominance 2)recessive inheritance 3)incomplete dominance 4)sex-linked inheritance
incomplete dominance
Sex chromosomes of a normal male are 1)XY 2)YY 3)XX 4)any of these, depending on the father
XY
Recessive genes are usually expressed in humans only when ________. 1)both alleles are exactly the same, or homozygous 2)the organism is in the embryonic stage 3)they are coding for skin color 4)they are coding for genetic diseases
both alleles are exactly the same, or homozygous
t or f: Most genetic disorders are inherited through dominant genes.
false
Continuous phenotypic variation between two extremes results from _______ 1)sex-linked inheritance 2)multiple-allele inheritance 3)incomplete dominance 4)polygenic inheritance
polygenic inheritance
An allele that can be masked or suppressed by another allele is said to be ___ 1)recessive 2)heterozygous 3)homozygous 4)dominant
recessive
Which of the following INCORRECTLY matches the term to its definition? 1)recessive/gene expressed when present 2)heterozygous/both a dominant and a recessive allele are present 3)genotype/genetic makeup 4)phenotype/physical appearance
recessive/gene expressed when present
Which type of inheritance involves genes found on an X chromosome? 1)sex-linked inheritance 2)multiple-allele inheritance 3)incomplete dominance inheritance 4)polygenic inheritance
sex-linked inheritance
Which of the following is an example of a disorder that exhibits incomplete dominance? 1)Tay-Sachs disease 2)syndactyly 3)cystic fibrosis 4)sickle-cell anemia
sickle-cell anemia
t or f: Hemophilia is an X-linked condition caused by a recessive gene.
true
The dominant gene is expressed when present; the recessive gene is expressed only in the absence of the dominant gene. 1)Polygenic inheritance 2)Dominant-recessive inheritance 3)Incomplete dominance 4)Sex-linked inheritance 5)Multiple-allele inheritance
Dominant-recessive inheritance
Which of the following is true concerning environmental influence on genetic expression? The only time a gene can be influenced by environmental factors is in the second trimester of pregnancy. 1)Environmental factors determine the way in which 90 percent of our genes are expressed. 2)Drugs and nutrition can alter normal gene expression. 3)It is impossible to alter in any way the expression of a gene in humans
Drugs and nutrition can alter normal gene expression.
Inheritance of the ABO blood group type is an example of this type of inheritance. 1)Polygenic inheritance 2)Dominant-recessive inheritance 3)Incomplete dominance 4)Sex-linked inheritance 5)Multiple-allele inheritance
Multiple-allele inheritance
t or f: Each human being (with the possible exception of identical siblings) has a unique genotype and phenotype.
True
The genetic determination of blood type is based on __________ inheritance. 1)sex-linked 2)polygene 3)dominant-recessive 4)multiple-allele
multiple-allele
Those characteristics that can be determined on superficial inspection of an individual are known as ________. 1)polyspermic 2)polygenic 3)phenotypic 4)genotypic
phenotypic
Use the following information to solve the problem using a Punnett square. Assume that the dominant "B" allele encodes brown eyes and the recessive "b" allele encodes blue eyes. An individual with the genotype BB has children by mating with an individual of the genotype bb. What is the percent chance that they would have children with blue eyes? 1)100% 2)25% 3)50% 4)0%
0%
If a cell has a diploid number of 22, how many total chromosomes should it have? 1)44 2)11 3)2 4)22
22
How many chromosomes are in a diploid human cell? 1)92 2)23 3)48 4)46
46
Three genes control skin color. How many possible combinations of skin color result from those three genes? 1)10 2)6 3)64 4)15
64
Genes for the same trait that have different expressions. 1)heterozygous 2)autosomes 3)dominant 4)allele
Allele
Chromosomes regulating most body characteristics. 1)heterozygous 2)autosomes 3)dominant 4)allele
Autosomes
The gene allele that suppresses or masks the expression of the other allele 1)heterozygous 2)autosomes 3)dominant 4)allele
Dominant
The heterozygote has a phenotype intermediate between those of the homozygous dominant and homozygous recessive. 1)Polygenic inheritance 2)Dominant-recessive inheritance 3)Incomplete dominance 4)Sex-linked inheritance 5)Multiple-allele inheritance
Incomplete dominance
Which of the following is true of the Punnett square? 1)It tells us the number of offspring an organism can produce. 2)It predicts only the probability of a particular genotype and phenotype. 3)It tells us, with a great degree of certainty, the different physical characteristics each offspring will display. 4)It tells us the number of offspring with a given genotype and phenotype that an organism can produce.
It predicts only the probability of a particular genotype and phenotype.
Is genetic diversity due entirely to inherited genes on the sex chromosomes? 1)Yes, because the male has a Y chromosome. 2)Yes, because genetic diversity is due to the Y influence on the autosomes. 3)No, because genetic diversity has nothing to do with the sex chromosomes but is due to crossing-over of chromosomes, independent assortment of chromosomes, and segregation of chromosomes.
No, because genetic diversity has nothing to do with the sex chromosomes but is due to crossing-over of chromosomes, independent assortment of chromosomes, and segregation of chromosomes.
Inheritance that results in continuous or qualitative phenotypic variations between two extremes; an example is skin color. 1)Polygenic inheritance 2)Dominant-recessive inheritance 3)Incomplete dominance 4)Sex-linked inheritance 5)Multiple-allele inheritance
Polygenic inheritance
Inherited traits determined by genes on the X or Y chromosomes. 1)Polygenic inheritance 2)Dominant-recessive inheritance 3)Incomplete dominance 4)Sex-linked inheritance 5)Multiple-allele inheritance
Sex-linked inheritance
The reason recessive genetic disorders are more frequent than disorders inherited as dominant is that ________. 1)people carrying dominant genetic disorders always die before birth 2)dominant genetic disorders are never expressed in males 3)carriers are not eliminated by the disease before passing the defective alleles on to their offspring 4)recessive genetic disorders are limited to persons of the same ethnicity
carriers are not eliminated by the disease before passing the defective alleles on to their offspring