AP Biology Midterm Part 3

1.

1 point

Independent assortment of chromosomes occurs

True for mitosis

True for meiosis 1

True for meiosis 2

True for mitosis and meiosis 1

True for mitosis and meiosis 2

2.

1 point

Independent assortment of chromosomes is a result of

The random and independent way in which each pair of homologous chromosomes lines up at the metaphase plate during meiosis 1

Random nature of the fertilization of ova by sperm

Random distribution of the sister chromatids to the two daughter cells during anaphase 2

Relatively small degree of homology shared by the X and Y chromosomes

all of the above

3.

1 point

How many unique gametes could be produced through independent assortment by an individual with the genotype AaBbCCDdEE?

4

8

16

32

64

4.

1 point

Mendels second law of independent assortment has its basis in which of the following events of Meisos 1

Synapsis of homologous chromosomes

Crossing over

Random alignment of tetrads at metaphase

Separation of chromatids at telophase

Separation of cells at telophase

5.

1 point

Black fur in mice (B dominant, b = brown). Short tails (T dominant, long = t). What fraction of the progeny crosses BbTt*BBtt will be expected it have black fur and long tails?

1/16

3/16

3/8

1/2

9/16

6.

1 point

Black fur in mice (B dominant, b = brown). Short tails (T dominant, long = t). What fraction of the progeny crosses BbTt*BBtt will be expected it have black fur and long tails?

1/16

3/16

3/8

1/2

9/16

7.

1 point

Two plants are cross. 3:1 ratio for a trait. What does it suggest?

Parents were true-breeding for contrasting traits

Trait shows incomplete dominance

Trait has blended

Parents were both heterozygous

Each offspring has the same alleles for each of two traits

8.

1 point

If a cell has completed the first meiosis division and is just beginning meiosis 2, which of the following is an appropriate description of its contents?

Half the DNA of the cell that began meiosis

Same number of chromosomes but each has different alleles than another cell from the same meiosis

It has half the chromosomes but twice the DNA of original cell

It has 1/4 DNA and 1/2 chromosomes

Identical to the original

9.

1 point

Which of the following might result in a human zygote with 45 chromosomes

An error in either egg or sperm meiosis anaphase

Failure of the egg nucleus to be fertilized by the sperm

Fertilization of a 23 chromosome human egg by a 22 chromosome sperm of a closely related species

An error in the alignment of chromosomes on the metaphase plate

Lack of chiasmata in prophase 1

10.

1 point

Given AABBCc*AabbCc, assume simple dominance for each trait and independent assortment. What proportion of the progeny will be expected to phenotypic ally resemble the first parent?

1/4

1/8

3/4

3/8

1

11.

1 point

Which of the following describes the ability of a single gene to have multiple phenotypic effects?

Incomplete dominance

Multiple alleles

Pleiotropy

Epistasis