Please circle the letter that precedes the most appropriate answer(s) to the question asked. Be aware, there is only one answer to each question. Consequently, if you feel that there is more than one plausible answer, choose the one that is most pertinent in answering the question.
1. If two genes demonstrate "independent assortment", which assumption is most likely true?
A Crossing over between the genes does not occur
B The two genes are located in very close proximity to each other on the same chromosome
C The two genes are located on the X chromosome.
D The expression of one gene has NO effect on the expression of the other
E The two genes are located on different chromosomes, or are far from each other on the same chromosome
2. Assuming that the height of a pea plant is determined by a single gene at a single locus, when crossing a tall pea plant (Tt ) with a dwarf pea plant (tt) which of the following statements would be true
A All the F1 generation would be heterozygous tall
B All the F1 generation would be homozygous small
C Half of the F1 generation would be homozygous small
D Half of the F1 generation would be homozygous tall
E If all the F1 generation were to be “selfed” 1/4 of the offspring would be homozygous small
F If all the F1 generation were to be “selfed” all the offspring would be heterozygous tall
3. Mendel’s 2nd law states that:
A During gamete formation the segregation of one gene pair is independent of all other gene pairs
B Two members of a gene pair segregate from each other into the gametes, whereby one half of the gametes carries one of the traits, the other half carries the other
C The union of one gamete from each parent to form a resultant zygote is random with respect to that particular characteristic.
D Like all things biological, genes come in pairs.
E When fertilization occurs, the zygote gets one half of its chromosomal set from each parent, thus restoring the pair.
4. The term “Monoecious” refers to:
A The number of chromosomes in a bacterial cell
B Having the male and female reproductive organs exhibited by the same individual
C Bacteria with only one membrane… i.e Gram Positive bacteria
D A genetic unit of hereditary
E The genetic complexity of a Mendelian type cell
F A general term for a cell going through the first stage of Meiosis
G Having the male and female reproductive organs in separate individuals.
5. A mother of four (2 girls and 2 boys) exhibits a recessive X-linked trait. Assuming that she married a man who did not, what is the most likely outcome for their offspring
(according to your knowledge of genetics and the laws of probability).
A All the offspring exhibit the trait.
B Both boys would appear to be wild-type.
C None of the girls would exhibit the trait
D None of the offspring would exhibit the trait.
E One of the girls would be a carrier, while the other would exhibit the trait.
F One of the boys would exhibit the trait, while the other would not.
6. In the ABO blood group system in humans, if a person of type-AB blood has children with a person of type-A blood, what blood types could their children potentially exhibit?
A Type A, Type B, Type AB
B Type B, Type AB
C Type A, Type B, Type O
D Type O, Type B, Type AB
E Type A & Type B
F It would depend up on the Rhesus antigen.
7. A trait is said to be “pleiotropic” when.
A It defines a phenotype that is highly variable
B it has more than three loci
C it is found in two different species
D it gives rise to more than one phenotype
E it masks the expression of other genes
8. The aneuploidic consequence of a non disjunction of chromosome 21 in Anaphase I of a cell undertaking meiotic cell division potentially includes: -careful
A Trisomy for chromosome 21 in one of the gametes
B Absence of chromosome 14 in one of the gametes
C Partial deletion of chromsome 21 in one of the gametes
D Diploidy of chromosome 21 in one of the gametes
E Tetraploidy of chromosome 21 in the gametes
F. Fusion of chromosome 14 with part of chromosome 21 in the gametes
9. Take a look at the figures below. Using the information given (as well as your knowledge of the course thus far) answer the question(s) that relate(s) to each by circling the most appropriate answer.
(Each part of the question is worth 2 pts.).
(a) The cell is in:
A Prophase II
D Metaphase II
E Anaphase I
F Telophase I
(b) This mammalian cell is:
A A “germ-line” cell
B A “recombinogenic” cell
C A “somatic” cell
D A “cancerous” cell
E There is insufficient information to discern.
(c) This cell is in:
A Prophase I
B Anaphase II
D Metaphase II
E Anaphase I
10. “Cytoplasmic / Maternal” inheritance relates to the “effect” of the genes in the “polar bodies” during Oogenesis.
11. If present the genotype of a dominant allele will always show through.
12. The genetics inheritance pattern of “Multiple genes” rarely, if ever, give rise to a Mendelian-like distribution of their phenotype
13. Almost by definition, all of the traits that Mendel analyzed in his dihybrid crosses were derived from genes that were located on different chromosomes.
14. Epistasis is the interaction between two or more genes such that expression of one gene masks the phenotypic expression of the other(s).
15. Sex-linked traits always refer to genes located on the X-chromosome.