Please indicate by “circling” the letter that precedes the most appropriate answer to the question asked. Be aware, there is only one answer to each question, if there are more than one plausible answers, choose the one that is most specific to the question asked.
2. What is meant by the term “test cross”
A The cross fertilization of an ovum with a spermatozoa
B A cross that checks whether or not individuals from two different species are compatible.
C A cross that checks whether or not individuals from the same species are compatible.
D A cross between a true breeding strain for a particular trait under scrutiny and a wild-type for the given trait.
E A cross between an individual and another individual that is a homozygous recessive for the particular trait under scrutiny
3. The term “Dioecious” refers to:
A The number of chromosomes in a bacterial cell
B exhibited by the same individual
C Bacteria with two membranes… i.e Gram Negative 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
4. Which one of the following examples from the lecture series would best fit into the category of having “multiple alleles”.
A Hair colour in donkeys
B Shape of the “purse” in Shepherd’s purse flowers
C ABO blood groups
D Height in humans
E Petal colour in carnations
5. Mendel’s 1st 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.
6. A mother of four (2 girls and 2 boys) exhibits a recessive X-linked trait. Assuming that the father does 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/show 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 or would not exhibit the trait.
F One of the boys would exhibit the trait, while the other would not.
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. During which phase of Mitosis are chiasmata visible under a light microscope
A Early Prophase I
B Metaphase I
C Late Interphase
D Late Prophase I
E Early Metaphase
F. Chiasmata aren’t normally visible in these cells
9. Take a look at the figures on the page below. Using the information given as well as your knowledge of the course thus far, answer the question(s) that relates 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) From your knowledge of the lectures, what type of organism/cell would “typify” this/these kinds of cell cycle(s):
A any eukaryotic cell
B a “recombinogenic” cell
C a “somatic” cell
D a mammalian cell
E. a yeast cell
F there is insufficient information to discern.
11. Which of the following statements about our current understanding of Mendelian genetics needs not be true?
A. Alternative forms of genes are called alleles.
B. A locus is a gene’s location on its chromosome.
C. Only two alleles can exist for a given gene.
D. A genotype is a description of the alleles that represent an individual’s genes
E. Individuals with the same phenotype can have different genotypes.
A Type A, Type B, Type AB
B Type A, Type AB
C Type A, Type B, Type O
D Type O, Type B, Type AB, Type A
E. Type A, Type B,
F It would depend up on the Rhesus antigen.
13. “Cytoplasmic / Maternal” inheritance relates to the “affect” of the genes in the “polar bodies” during Oogenesis.
______ “Cytoplasmic / Maternal” inheritance refers to inheritance of mitochondrial/plastid DNA_
14. The environment does, sometimes, play a role in determining the phenotype for a given trait
15. Almost by definition, all of the traits that Mendel analyzed in his dihybrid crosses were derived from genes that were located on different chromosomes.
______At least three of the seven traits were on the same chromosome as at least one other trait,
______but agree with Mendel because of “chiasmata”_________________________________
16. Epistasis is the interaction between two or more genes such that expression of one gene masks the phenotypic expression of the other(s).
17. Almost by definition, the term “sex-linked traits” always refer to genes located on the
______X-linked, true, “sex-linked” false, because the Y chromosome is also a Sex chromosome
16. Dominant traits are always the “Wild-type” traits
_____As emphasized at least three times, “Dominant” does not equate to “wild-type” ________
_____-think Huntington’s disease”, ________________________________________________