UJIAN GENETIKA STANDARD

1. Two true breeding parents are crossed similar to Mendel's P generation. A tall plant is crossed with a short plant. What is the expected outcome for the F1 generation?

A.      all short

B.      all tall

C.      all medium height

D.      half tall, half short

2. If the cross from #1 is continued, what would be the expected outcome in the F2 generation?

A.      all short

B.      all tall

C.      3 tall, 1 short

D.      half tall, half short

3. If a plant that has round seeds has a parent that has wrinkled seeds, what is its genotype? (Assume that round is dominant.)

A.      RR

B.      Rr

C.      rr

D.      RrWw

4. This principle states that alleles separate during gamete formation:

A.      principle of multiple alleles

B.      principle of dominance and recessiveness

C.      principle of independent assortment

D.      principle of segregation

5. If you crossed two heterozygous plants, how many of the offspring will also be heterozygous?

A.      all

B.      half

C.      3/4

D.      1/4

6. A plant that has purple flowers is crossed with one that has white flowers. The offspring were half white and half purple. What were the genotypes of the parents?

A.      Pp x pp

B.      Pp x Pp

C.      PP x pp

D.      PP x WW

7. A dihybrid cross (AaBb x AaBb) will result in what offspring ratio?

A.      4:4:2:2

B.      1:3:1

C.      3:1

D.      9:3:3:1

8. Phenotype refers to an organism's:

A.      genetic code

B.      physical appearance

C.      ratio

D.      parents

9. In each case where Mendel crossed true breeding plants as parents, the offspring displayed only one of the two traits seen in the parents. This observation supports which principle of genetics?

A.      segregation

B.      independent assortment

C.      dominance and recessiveness

D.      allele frequency

10. Which of the following outcomes would you expect from the following cross: tall, round (TTRR) x short, wrinkled (ttrr)

A.      all offspring tall and round

B.      all offspring short and wrinkled

C.      half tall, round; half short wrinkled

D.      9:3:3:1

11.          An epistatic allele in labrador retrievers ensures that ee lab pups are yellow. Two other alleles control coat color, where black is dominant to brown. How many yellow pups would you expect from a parental cross where one parent was yellow (Bbee) and the other was heterozygous black.

A.        1/8

B.        1/2

C.        3/8

D.        1/4

12.          In mice, agouti coat color is codominant. Hairs, when viewed under a microscope are grey at the base and white at the tip. An agouti mouse will result from a cross between a black parent and a white parent. What will two agouti mice produce?

A.        all agouti offspring

B.        half black, half agouti offspring

C.        half agouti offspring, 1/4 white, 1/4 black

D.        half black, half white offspring

13.          A type of muscular dystrophy is sex linked. If a woman is a carrier for the disease, what proportion of her SONS will have the disease.

A.        all

B.        1/2

C.        1/4

D.        3/4

14.          A farmer discovers an oddity among his sheep where some of the sheep have abnormally large eyes and bowed legs. Crosses of these sheep show that 2/3 of the offspring have a normal phenotype and 1/3 have the abnormal phenotype. What is the best explanation for the type of inheritance that occurs here?

A.        the allele is lethal in its dominant form

B.        the allele is completely recessive

C.        the allele is codominant

D.        the allele is dominant

15.          The farmer is still unsure with his conclusions so he breeds more sheep together. Out of 100 matings, 35 are abnormal. How can he verifiy his hypothesis?

A.        use the hardy-weinberg equation

B.        develop a mouse-model of the gene

C.        perform a chi square analysis

D.        clone the abnormal sheep

16.          In cats, the gene for calico coat color is both codominant and sex-linked. If a black and yellow cat are mated, what will be the result?

A.        all female offspring will be calico

B.        all male offspring will be calico

C.        half of the females will be calico, half of the males will be calico

D.        all the male offspring will be black

17.          A man with hemophilia (sex linked) lives a full life through modern medicine. He eventually marries and wants to have children, but his wife is worried that their children will have the disease. What phenotypes are likely in their children?

A.        all of the sons will have hemophilia

B.        half of the sons will have hemophilia

C.        all of the daughters will have hemophilia

D.        none of the children will have the disease (assuming his wife is not a carrier)

18.          Which of the following is a trait that is controlled by multiple alleles?

A.        hemophilia

B.        blood type

C.        hitchhiker's thumb

D.        cystic fibrosis

19.          If a man has blood type O and his wife has blood type AB, what blood types are possible among their children?

A.        A only

B.        B only

C.        A and B

D.        only

20.          Dwarfism is a dominant allele that is also lethal in a homozygous state. If two dwarfs are married, what are the odds that their child will not be viable (able to survive)

A.        1/2

B.         1/4

C.         3/4

D.        1/8

21.     A human being has _____ autosomes and ______ sex chromosomes

A.           23, 1

B.           22 pairs, 1 pair

C.           23, 23

D.           2, 2

22. A section of chromosomes that codes for a trait can be called a(n):

A.           nucleotide

B.           base-pair

C.           gene

D.          nucleus

23. Somatic cells of a human have ____ chromosomes and are called ____

A.           10, haploid

B.           92, diploid

C.           23, haploid

D.           46, diploid

24. A person who receives an extra chromosome, could have:

A.           Heightened intelligence

B.           Down Syndrome

C.           Red eyes

D.           Polygenic traits

25. Each chromosome consists of two identical:

A.           genes

B.           nuclei

C.           chromatids

D.           bases

26. If a person receives an X and a Y chromosome, that person is:

A.           female

B.           male

C.           red eyed

D.           mentally challenged

27. Two alleles for pea plant height are designated T (tall) and t (dwarf). These alleles are found on:

A.           genes

B.           sex chromosomes

C.           ribosomes

D.           homologous chromosomes

28. An animal has 40 chromosomes in its gametes, how many chromosomes would you expect to find in this animal's brain cells?

A.           1

B.           20

C.           40

D.           80

29. A picture of a person's chromosomes is called a(n):

A.           karyotype

B.           syndrome

C.           chromatin

D.           fingerprint

30. During which phase of mitosis is DNA replicated?

A.           interphase

B.           prophase

C.           anaphase

D.           telophase

 

31 Consider the following traits: Widow's peak (dominant) and Tongue twisting (recessive). If a person is Pptt is married to a person who is ppTt, what proportion of their offspring will have a widow's peak and can twist their tongue?

A.               1/2

B.               1/16

C.               1/4

D.               3/16