Biology Test: Chapter 6 Introduction to Genetics
1. _____ What type of allele is always expressed?
a. dominant allele b. homologous allele
c. recessive allele d. incomplete allele
2. _____In pea plants, the tallness or shortness is known as
a. genotype b. phenotype
c. dominance d. gametes
3. _____ The haploid number of chromosomes for a human is
a. 23 b. 26 c. 46 d. 92
4. _____ Cells that contain only a single set of chromosomes are
a. homologous b. haploid
c. diploid d. heterozygous
5. _____ Which process reduces the number of chromosomes in a diploid cell by half to produce gametes?
a. mitosis b. codominance c. crossing-over d. meiosis
6. _____An identical pair of alleles for a trait(TT or tt) has what type of genotype?
a. homologous b. homozygous c. heterozygous d. segregation
7. _____ In the cross Tt x tt, what percentage of pea plants will be short?
a. 50 b. 75 c. 25 d. 100
8. _____ Crossing different true-breeding(purebred) stocks produces offspring called
a. P generation b. F2 generation c. cross-overs d. hybrids
9. _____ The different forms of a gene are called
a. traits b. alleles c. gametes d. hybrids
10. _____Crossing over is the exchange of genetic information between
a. reproductive cells b. diploid cells
c. any 2 chromosomes d. homologous chromosomes
11. In a pea plant, axial flower position is dominant over terminal flower position. What genotype and phenotype ratios will result if a heterozygous axial pea plant is crossed with a pea plant with terminal flowers? (Show work)
12. During metaphase I of meiosis, homologous chromosomes line up at the equator of a cell.
A) Diagram this in a cell with four chromosomes.
B) Label: chromosome, chromatid, spindle fiber, pole, centromere, tetrad
C) Explain what happens next.
13. Look at the diagram below of Polygenic Inheritance Parakeets.
· Draw a diagram how a blue and a yellow parakeet may produce a yellow parakeet. Be sure to show which gametes are used from each parakeet to produce a green parakeet.
14. A female horse that is pure black and a pure trotter is crossed with a male horse that is hybrid for both traits.
A) What are the genotypes of the parents?
B) What gametes are produced by each of the parents?
C) Draw a Punnet square representing this cross.
D) What are the genotypic and phenotypic ratios that result?
Genotype:
Phenotype:
During which phase(s), does following occur? Write the correct answer on the line provided. For some, there may be more than one answer.
S phase of Interphase Prophase I Prophase II Metaphase I
Metaphse II Anaphase I Anaphase II Telophase I
Telophase II
1. ______The chromosomes line up as a tetrad at the equator.
2. ______The chromosomes move to the poles.
3. ______The spindle fiber shortens.
4.______DNA synthesis occurs.
5. ______Homologous chromosomes pair up at the equator.
6. ______The cell membrane pinches forward.
7. ______The sister chromatids divide and move apart.
8.______Chromosomes lined up at the equator is not in a tetrad.
9.______Homologous chromosomes BEGIN to pair up.
10.______Sister chromatids, still joined, move toward the poles.