BIOLOGY 207 FINAL EVALUATION QUESTIONS WITH
SOLUTIONS GRADED A+ 2025/2026
✔✔hypermorph - ✔✔mutation that causes more than wild type level of gene expression
✔✔neomorph - ✔✔mutation that creates a new/different function from the wild type
function
✔✔antimorph - ✔✔mutant that results in the reduction or loss in normal function
✔✔leptotene - ✔✔interphase nucleus begins to condense into visible, long, thin threads
(chromosomes)
✔✔zygotene - ✔✔homologous chromosomes begin to pair up or synapse
✔✔pachytene - ✔✔chromosomes are fully synapses as bivalent
- crossing over takes place
- reciprocal exchange between non-sister chromatids
✔✔diplotene - ✔✔pairing loosens & chromosomes start to separate
- chromatids become visually apparent
- chiasmata appear - visible result of crossover event
✔✔diakinesis - ✔✔continuation/extension of diplotene
- form compact chromosomes, which are easier to move to daughter cells than larger
chromosomes
✔✔intrachromosomal recombination - ✔✔recombination among genes located on the
same chromosome
- crossing over
✔✔interchromosomal recombination - ✔✔recombination among genes on different
chromosomes
- independent assortment
✔✔Law of Segregation - ✔✔proper segregation of alleles ensures that one allele of the
pair is present in a gamete
✔✔law of independent assortment - ✔✔the law that states that genes separate
independently of one another
✔✔9:3:3:1 - ✔✔phenotypic ratio of a dihybrid cross
- expected for gene loci that assort independently
, ✔✔gene loci that assort independently: - ✔✔- located on different chromosomes
- located far apart on the same chromosome
✔✔syntenic - ✔✔genes located on the same chromosome
✔✔coupling - ✔✔mutants from the same parents
✔✔repulsion - ✔✔mutants from different parents
✔✔parthenogenesis - ✔✔females lay fertile eggs (no male required)
✔✔testis determining factor (TDF) - ✔✔protein encoded by a gene in the SRY that
triggers testes formation
- responsible for person developing as male
✔✔pseudoautosomal region - ✔✔small region on the X and Y chromosomes that
contains homologous gene sequences
- allows X & Y chromosomes to act as homologous pairs in meiosis
✔✔Y-linked genes - ✔✔genes located on Y-chromosome
- father to son transmission only
✔✔X-linked genes - ✔✔genes located on X-chromosome
- fathers always transmit to daughters only
- mother transmits equally to both daughters & sons
✔✔sex-linked trait - ✔✔an inherited characteristic for which there is a gene on the X or
Y chromosome but not on the other
✔✔sex-limited trait - ✔✔associated with genes that are expressed in only one sex & not
in the other
- cause the two sexes to show different traits or phenotypes despite same genotype for
loci involved
- gene are typically present on autosomes
✔✔reciprocal cross - ✔✔a cross in which the phenotypes of the male and female are
reversed compared with a prior cross
- autosomal gene -> the same pattern of inheritance is seen in reciprocal cross
- sex linked genes -> different pattern of inheritance seen in reciprocal cross
✔✔Y-linked Traits - ✔✔- gene on Y chromosome
- only males affected
- affected male transmits to ALL sons
SOLUTIONS GRADED A+ 2025/2026
✔✔hypermorph - ✔✔mutation that causes more than wild type level of gene expression
✔✔neomorph - ✔✔mutation that creates a new/different function from the wild type
function
✔✔antimorph - ✔✔mutant that results in the reduction or loss in normal function
✔✔leptotene - ✔✔interphase nucleus begins to condense into visible, long, thin threads
(chromosomes)
✔✔zygotene - ✔✔homologous chromosomes begin to pair up or synapse
✔✔pachytene - ✔✔chromosomes are fully synapses as bivalent
- crossing over takes place
- reciprocal exchange between non-sister chromatids
✔✔diplotene - ✔✔pairing loosens & chromosomes start to separate
- chromatids become visually apparent
- chiasmata appear - visible result of crossover event
✔✔diakinesis - ✔✔continuation/extension of diplotene
- form compact chromosomes, which are easier to move to daughter cells than larger
chromosomes
✔✔intrachromosomal recombination - ✔✔recombination among genes located on the
same chromosome
- crossing over
✔✔interchromosomal recombination - ✔✔recombination among genes on different
chromosomes
- independent assortment
✔✔Law of Segregation - ✔✔proper segregation of alleles ensures that one allele of the
pair is present in a gamete
✔✔law of independent assortment - ✔✔the law that states that genes separate
independently of one another
✔✔9:3:3:1 - ✔✔phenotypic ratio of a dihybrid cross
- expected for gene loci that assort independently
, ✔✔gene loci that assort independently: - ✔✔- located on different chromosomes
- located far apart on the same chromosome
✔✔syntenic - ✔✔genes located on the same chromosome
✔✔coupling - ✔✔mutants from the same parents
✔✔repulsion - ✔✔mutants from different parents
✔✔parthenogenesis - ✔✔females lay fertile eggs (no male required)
✔✔testis determining factor (TDF) - ✔✔protein encoded by a gene in the SRY that
triggers testes formation
- responsible for person developing as male
✔✔pseudoautosomal region - ✔✔small region on the X and Y chromosomes that
contains homologous gene sequences
- allows X & Y chromosomes to act as homologous pairs in meiosis
✔✔Y-linked genes - ✔✔genes located on Y-chromosome
- father to son transmission only
✔✔X-linked genes - ✔✔genes located on X-chromosome
- fathers always transmit to daughters only
- mother transmits equally to both daughters & sons
✔✔sex-linked trait - ✔✔an inherited characteristic for which there is a gene on the X or
Y chromosome but not on the other
✔✔sex-limited trait - ✔✔associated with genes that are expressed in only one sex & not
in the other
- cause the two sexes to show different traits or phenotypes despite same genotype for
loci involved
- gene are typically present on autosomes
✔✔reciprocal cross - ✔✔a cross in which the phenotypes of the male and female are
reversed compared with a prior cross
- autosomal gene -> the same pattern of inheritance is seen in reciprocal cross
- sex linked genes -> different pattern of inheritance seen in reciprocal cross
✔✔Y-linked Traits - ✔✔- gene on Y chromosome
- only males affected
- affected male transmits to ALL sons
