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Example Questions
Example Question #16 : Understanding Autosomal And Sex Linked Inheritance
What is an autosome?
The Y chromosome
A non-sex chromosomes
The X chromosome
Both the X and Y chromosomes
A non-sex chromosomes
Autosomes are all the chromosomes that do not determine an individual's sex. X and Y chromosomes both determine sex, and are sex chromosomes. The other 22 pairs of chromosomes are autosomes.
Example Question #17 : Understanding Autosomal And Sex Linked Inheritance
Fertilization results in __________.
a haploid cell
an autosome
a zygote
a gamete
a zygote
The union of two gametes is called fertilization, which results in a zygote. The zygote is a diploid cell that will grow into the entire organism.
Example Question #171 : Evolution And Genetics
A human haploid cell will have how many chromosomes?
A haploid cell has only one set of chromosomes as compared to the two sets normally found in diploid cells. In a haploid cell there are 22 autosomes and 1 sex chromosome for a total of 23 chromosomes.
Example Question #172 : Evolution And Genetics
When two human haploid cells fuse together the resulting cell will have how many chromosomes?
Haploid cells have 23 chromosomes each (22 autosomes and 1 sex chromosome) so when they fuse the resulting cell will have 46 chromosomes (44 autosomes and 2 sex chromosomes). This idea is demonstrated during fertilization, where two haploid cells (gametes) fuse to form the zygote, which is diploid.
Example Question #173 : Evolution And Genetics
A human somatic cell has how many chromosomes?
44
A somatic cell is a diploid cell so it will have 22 pairs of autosomes and one pair of sex chromosomes for a total of 46 chromosomes.
Example Question #171 : Evolution And Genetics
A certain mutation is a sex-linked recessive. If a father is not affected and the mother is affected, what is the probability that the couple will have an affected son?
If a disease is sex linked recessive, the disease resides on the x-chromosome (unless otherwise stated). The question asks about males, who genetically have one x-chromosome and one y-chromosome. The easiest way to solve this problem is to create a punnet square (shown below).
As you can see, there is a 100% chance that the males will be affected. Similarly, there is a 100% chance that the daughters will be carriers of the disease. As a side note, the daughters will not be affected because they have one "good" x-chromosome to compensate for the "bad" x-chromosome that carries the mutation.
Example Question #1674 : Ap Biology
Which of the following is not an example of trisomy?
Patau
Downs
Kleinfelters
Turners
Edwards
Turners
Trisomy is a condition of an extra chromosome copy, such as in Patau (trisomy 13), Edwards (trisomy 18), Kleinfelters (XXY), and Downs (trisomy 21). Turners syndrome is a condition of monosomy (X).
Example Question #22 : Inheritance
Using the genotype below, and assuming there is no gene linkage present, answer the following question.
AABbCcDdEeFf
How many different possible gametes could be formed?
Each homozygous pair of alleles will result in 100% identical dominant or recessive alleles, therefore cross multiple "1" for each homozygous pair and multiple "2" for each heterozygous pair.
Therefore, the appropriate multiplication for determining the number of possible gene combinations is
Example Question #174 : Evolution And Genetics
Which of the following does not result from nondisjunction of homologous chromosomes during meiosis?
Trisomy XXY (Klinefelter's)
Monosomy X (Turner's Syndrome)
Trisomy 18 (Edward's Syndrome)
Trisomy 21 (Down's Syndrome)
All of these result from nondisjunction
All of these result from nondisjunction
All of the following are results of a nondisjunction event. Trisomy and monosomy disorders may occur as a result of improper separation in diploid human meiosis events.
Example Question #175 : Evolution And Genetics
Disease A is inherited through an autosomal recessive process. What is the probability that two unaffected carriers of this disease will produce an offspring that inherits disease A?
75%
0%
50%
25%
100%
25%
The correct answer is 25% because each parent has a 50% chance of giving up their recessive allele to the offspring. There are two parents so the probability will be:
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