BIO 212 Final Exam Questions and Answers Fully Solved Latest Update 2025-2026
Early inheritance worked under two assumptions about how inheritance works:
Reciprocal crosses - Answers Each parent contributes equally to offspring in reciprocal crosses
(supported by experiments)
Early inheritance worked under two assumptions about how inheritance works:
Hereditary determinants - Answers Hereditary determinants blend in offspring (not supported by
experiments)
Each parent contributes ________ to offspring - Answers Each parent contributes equally to
offspring. (correct)
Supported by reciprocal crosses, 1770s by Kolreuter
Hereditary determinants blend in the offspring - Answers Incorrect. It was thought that once
hereditary elements had blended they could never be separated.
Gregor Mendel's studies refuted this
Mendel - Answers Austrian monk
His studies in physics and mathematics were a strong influence on his use of quantitative
experimental methods.
Over seven years, he made crosses with 24,034 plants
Mendel's new theory of inheritance - Answers Published in 1866, but was largely ignored
Most biologists at the time were not used to thinking in mathematical terms
Even Darwin missed the significance of Mendel's work
1900 - Answers Meiosis had been observed
Three plant geneticists realized that chromosomes and meiosis provided a physical explanation
for Mendel's results
Mendel worked with the - Answers garden pea
He could control pollination and fertilization- and be sure of the parents of offspring
Available, short life span from seed to seed. Produce large numbers of offspring, easily
grown/cultured, different strains= different reproducible characteristics
Peas= self fertile. Cross with themselves. Control from one plant to another
,Character - Answers Observable physical feature (e.g., flower color)
Trait - Answers Form of a character (e.g., purple flowers or white flowers)
Heritable trait - Answers Passed from parent to offspring
Mendel looked for well-defined, true-breeding traits - Answers The observed trait is the only one
present for many generations
True-breeding strains - Answers were isolated by inbreeding and selection
He concentrated on seven traits
Mendel's crosses:
Parental generation=P - Answers Pollen from one parent was transferred to the stigma of the
other parent
Parental generation=P
Mendel's crosses:
First filial generation= F1 - Answers Resulting offspring
First filial generation or F1
Mendel's crosses:
Second filial generation= F2 - Answers If F1 plants self pollinate, produce second filial
generation or F2
Mendel's Postulates
Unit Factors - Answers Traits are controlled by discrete 'unit factors' (genes)
Unit Factors are present in pairs (concept of diploid before anyone had ever seen chromosomes)
Mendel's Postulates
Alleles - Answers There are different 'flavors of unit factors for particular traits (tall vs. dwarf are
types of gene or unit factor for plant height. Alleles.
Mendel's Postulates
Disimilar pairs can be present - Answers One tall, one dwarf form of that gene
One will be expressed, the other is masked
,Mendel's Postulates
Dominant - Answers gene expressed
Mendel's Postulates
Recessive - Answers gene masked
Mendel's Postulates
Heterozygous - Answers 2 alleles of a gene that are dissimilar
Mendel's Postulates
Homozygous - Answers 2 alleles of a gene that are the same
Mendel's Postulates
Law of Segregation - Answers During formation of sex cells (eggs and sperm= gametes) unit
factors separate (segregate)
Each gamete gets one or the other but not both
Mendel's first experiment - Answers Crossed plants differing in just one trait (P)
F1 generation are monohybrids
The monohybrids were then allowed to self pollinate to form the F2 generation
Mendel repeated this for all seven traits
Mendel's first experiment
Monohybrid cross - Answers Self pollination
Forms F2 generation
Mendel's first experiment
Recessive traits - Answers One trait of each pair disappeared in the F1 generation and
reappeared in the F2 generation
Mendel's first experiment
Dominant trait - Answers The trait that appears in the F1 generation is the dominant trait
Ratio of dominant to recessive in the F2 generation - Answers About 3:1
Reciprocal crosses yield the same results - Answers It made no difference which parent
contributed pollen
, The idea that each parent contributes equally was supported
Blending theory - Answers Not supported by Mendel's crosses
Particulate theory - Answers Mendel proposed that the heritable units were discrete particles
Each plant has two particles for each character, one from each parent
Diploid - Answers The two copies of heritable unit in an organism
Haploid - Answers During gamete production, only one copy is given to the gamete- this single
set is called haploid
Gamete vs. zygote - Answers Mendel also concluded that each gamete contains only one
particle (or unit), but the zygote contains two- because it is produced from the fusion of two
gametes
The "Particles" are now called ________ - Answers Genes
Genome - Answers The totality of all genes in an organism is the genome
Hypothesis - Answers When two strains of peas with contrasting traits are bred, their
characteristics are irreversibly blended in succeeding generations
Method - Answers Plant a true-breeding spherical seed- Parental (P) seed
Plant a true-breeding wrinkled seed Parental (P) seed
Seeds grow into plants and produce pollen- Parental (P) plants
F1 seeds are formed and grown into F1 plants
F1 plant self-pollinates
Results - Answers F2 seeds from F1 plants
3 spherical seeds, 1 wrinkled seed
Conclusion - Answers The hypothesis is rejected. There is no irreversible blending of
characteristics, and a recessive trait can reappear in succeeding generations
The true-breeding plants in the P generation had - Answers Two identical copies of the particle
(gene) for each character
Example: Spherical SS; wrinkled ss gametes from SS will have one S gametes from ss will have
one s offspring (F1) will be Ss
S is dominant; s is not expressed in F1
Early inheritance worked under two assumptions about how inheritance works:
Reciprocal crosses - Answers Each parent contributes equally to offspring in reciprocal crosses
(supported by experiments)
Early inheritance worked under two assumptions about how inheritance works:
Hereditary determinants - Answers Hereditary determinants blend in offspring (not supported by
experiments)
Each parent contributes ________ to offspring - Answers Each parent contributes equally to
offspring. (correct)
Supported by reciprocal crosses, 1770s by Kolreuter
Hereditary determinants blend in the offspring - Answers Incorrect. It was thought that once
hereditary elements had blended they could never be separated.
Gregor Mendel's studies refuted this
Mendel - Answers Austrian monk
His studies in physics and mathematics were a strong influence on his use of quantitative
experimental methods.
Over seven years, he made crosses with 24,034 plants
Mendel's new theory of inheritance - Answers Published in 1866, but was largely ignored
Most biologists at the time were not used to thinking in mathematical terms
Even Darwin missed the significance of Mendel's work
1900 - Answers Meiosis had been observed
Three plant geneticists realized that chromosomes and meiosis provided a physical explanation
for Mendel's results
Mendel worked with the - Answers garden pea
He could control pollination and fertilization- and be sure of the parents of offspring
Available, short life span from seed to seed. Produce large numbers of offspring, easily
grown/cultured, different strains= different reproducible characteristics
Peas= self fertile. Cross with themselves. Control from one plant to another
,Character - Answers Observable physical feature (e.g., flower color)
Trait - Answers Form of a character (e.g., purple flowers or white flowers)
Heritable trait - Answers Passed from parent to offspring
Mendel looked for well-defined, true-breeding traits - Answers The observed trait is the only one
present for many generations
True-breeding strains - Answers were isolated by inbreeding and selection
He concentrated on seven traits
Mendel's crosses:
Parental generation=P - Answers Pollen from one parent was transferred to the stigma of the
other parent
Parental generation=P
Mendel's crosses:
First filial generation= F1 - Answers Resulting offspring
First filial generation or F1
Mendel's crosses:
Second filial generation= F2 - Answers If F1 plants self pollinate, produce second filial
generation or F2
Mendel's Postulates
Unit Factors - Answers Traits are controlled by discrete 'unit factors' (genes)
Unit Factors are present in pairs (concept of diploid before anyone had ever seen chromosomes)
Mendel's Postulates
Alleles - Answers There are different 'flavors of unit factors for particular traits (tall vs. dwarf are
types of gene or unit factor for plant height. Alleles.
Mendel's Postulates
Disimilar pairs can be present - Answers One tall, one dwarf form of that gene
One will be expressed, the other is masked
,Mendel's Postulates
Dominant - Answers gene expressed
Mendel's Postulates
Recessive - Answers gene masked
Mendel's Postulates
Heterozygous - Answers 2 alleles of a gene that are dissimilar
Mendel's Postulates
Homozygous - Answers 2 alleles of a gene that are the same
Mendel's Postulates
Law of Segregation - Answers During formation of sex cells (eggs and sperm= gametes) unit
factors separate (segregate)
Each gamete gets one or the other but not both
Mendel's first experiment - Answers Crossed plants differing in just one trait (P)
F1 generation are monohybrids
The monohybrids were then allowed to self pollinate to form the F2 generation
Mendel repeated this for all seven traits
Mendel's first experiment
Monohybrid cross - Answers Self pollination
Forms F2 generation
Mendel's first experiment
Recessive traits - Answers One trait of each pair disappeared in the F1 generation and
reappeared in the F2 generation
Mendel's first experiment
Dominant trait - Answers The trait that appears in the F1 generation is the dominant trait
Ratio of dominant to recessive in the F2 generation - Answers About 3:1
Reciprocal crosses yield the same results - Answers It made no difference which parent
contributed pollen
, The idea that each parent contributes equally was supported
Blending theory - Answers Not supported by Mendel's crosses
Particulate theory - Answers Mendel proposed that the heritable units were discrete particles
Each plant has two particles for each character, one from each parent
Diploid - Answers The two copies of heritable unit in an organism
Haploid - Answers During gamete production, only one copy is given to the gamete- this single
set is called haploid
Gamete vs. zygote - Answers Mendel also concluded that each gamete contains only one
particle (or unit), but the zygote contains two- because it is produced from the fusion of two
gametes
The "Particles" are now called ________ - Answers Genes
Genome - Answers The totality of all genes in an organism is the genome
Hypothesis - Answers When two strains of peas with contrasting traits are bred, their
characteristics are irreversibly blended in succeeding generations
Method - Answers Plant a true-breeding spherical seed- Parental (P) seed
Plant a true-breeding wrinkled seed Parental (P) seed
Seeds grow into plants and produce pollen- Parental (P) plants
F1 seeds are formed and grown into F1 plants
F1 plant self-pollinates
Results - Answers F2 seeds from F1 plants
3 spherical seeds, 1 wrinkled seed
Conclusion - Answers The hypothesis is rejected. There is no irreversible blending of
characteristics, and a recessive trait can reappear in succeeding generations
The true-breeding plants in the P generation had - Answers Two identical copies of the particle
(gene) for each character
Example: Spherical SS; wrinkled ss gametes from SS will have one S gametes from ss will have
one s offspring (F1) will be Ss
S is dominant; s is not expressed in F1
