p.25
Sex Linkage and Inheritance Patterns
What is red-green colorblindness?
A sex-linked recessive trait characterized by the inability to see red and green.
p.25
Sex Linkage and Inheritance Patterns
Do sons inherit their father's sex-linked traits?
No, fathers pass their X chromosome (with the trait) to daughters and the Y chromosome to sons.
p.4
Key Genetic Terms and Definitions
What are the two types of allele combinations in diploid organisms?
Homozygous and heterozygous.
p.4
Mendelian Genetics and Laws
What restores the diploid number of chromosomes in offspring?
The fusion of haploid gametes during fertilization.
p.22
Mendelian Genetics and Laws
What is the focus of Fig. 4?
Examples of crosses between rabbits with different coats.
p.6
Mendelian Genetics and Laws
What is the physical basis of Mendelian inheritance?
The behavior of chromosomes.
p.29
Sex Linkage and Inheritance Patterns
What condition is the man diagnosed with after taking primaquine?
Glucose 6-phosphate deficiency.
p.4
Genetics and Inheritance Overview
How does random fusion of gametes contribute to genetic variation?
It creates different combinations of alleles in the organism.
p.25
Sex Linkage and Inheritance Patterns
What happens when a male with colorblindness has a daughter?
The daughter will become a carrier if her other X chromosome carries a normal allele.
p.25
Sex Linkage and Inheritance Patterns
Why must we differentiate between males and females for sex-linked traits?
Because the alleles are located on the sex chromosomes, and gender itself is a phenotypic difference.
p.8
Mendelian Genetics and Laws
What do homologous chromosomes have in common?
The alleles occupy the same position on separate chromosomes.
p.7
Genetic Diagrams and Problem Solving
What does a Punnett square represent?
All possible outcomes of a genetic cross.
p.15
Mendelian Genetics and Laws
What two pairs of alleles determine seed characters in Pisum sativum?
Green and yellow; round and wrinkled.
p.15
Monohybrid and Dihybrid Crosses
In the first cross, what are the phenotypes of the parents?
Yellow round and green wrinkled.
p.11
Dihybrid and Law of Independent Assortment
What is Dihybrid Inheritance?
Inheritance of 2 pairs of contrasting characteristics simultaneously (i.e., 2 genes).
p.1
Genetics and Inheritance Overview
How does genotype affect phenotype?
Genotype determines the traits expressed in the phenotype.
p.5
Mendelian Genetics and Laws
Why is the allele coding for a functional protein usually dominant?
Because it produces some functional protein in heterozygous cells, which is usually sufficient for the desired effect.
p.21
Multiple Alleles and Blood Groups
What is the significance of the allele inheritance in blood group determination?
A child inherits one allele from each parent, determining their blood group.
p.1
Codominance and Incomplete Dominance
What is codominance?
A genetic scenario where both alleles in a heterozygote are fully expressed.
p.23
Sex Linkage and Inheritance Patterns
What is the homogametic sex?
The sex that produces only one kind of gamete (e.g., females with XX genotype).
p.11
Dihybrid and Law of Independent Assortment
What are the alleles for yellow and green seeds?
Y = allele for yellow seed, y = allele for green seed.
p.16
Mendelian Genetics and Laws
What are the dominant and recessive alleles for resistance to race 22?
A (dominant) for resistance and a (recessive) for susceptibility.
p.4
Genetics and Inheritance Overview
What mechanisms during meiosis ensure genetic variation?
Crossing over and independent assortment.
p.29
Sex Linkage and Inheritance Patterns
What type of trait is glucose 6-phosphate deficiency?
A sex-linked recessive trait.
p.25
Sex Linkage and Inheritance Patterns
How should alleles for sex-linked traits be represented?
They must be written on the sex chromosome.
p.24
Sex Linkage and Inheritance Patterns
What are two examples of sex-linked traits?
Red-green color blindness and hemophilia.
p.1
Dihybrid and Dihybrid Crosses
What is a dihybrid cross?
A genetic cross involving two traits.
p.15
Monohybrid and Dihybrid Crosses
What is the progeny distribution for the first cross?
138 yellow round, 143 yellow wrinkled, 137 green round, 142 green wrinkled.
p.7
Genetic Diagrams and Problem Solving
What are the male and female gametes represented in the Punnett square?
Male: T, t; Female: T, t.
p.12
Mendelian Genetics and Laws
What traits were observed in the F1 progeny?
All round and yellow, indicating these traits are dominant.
p.2
Key Genetic Terms and Definitions
What are alleles?
Alternative forms of a gene, each with a slightly different nucleotide sequence, coding for different forms of the same trait.
p.2
Key Genetic Terms and Definitions
How many alleles does a diploid cell contain for the same gene?
Two alleles, one on each of the pair of homologous chromosomes.
p.25
Sex Linkage and Inheritance Patterns
Why are sex-linked recessive traits more common in men than women?
Men have no corresponding allele on the Y chromosome to mask the effect of the recessive allele on the X chromosome.
p.24
Sex Linkage and Inheritance Patterns
Which chromosome carries more genes related to sex-linked traits?
The X chromosome carries many such genes, while the Y chromosome has very few.
p.1
Key Genetic Terms and Definitions
What are the two main types of genetic expressions?
Genotypes and phenotypes.
p.29
Codominance and Incomplete Dominance
How many classes of coat color would you find in male cats?
Two classes: black and ginger.
p.21
Multiple Alleles and Blood Groups
What are the genotypes of parents with blood groups A and B?
IAIO (blood group A) and IBIO (blood group B).
p.8
Mendelian Genetics and Laws
What is the chromosome number in each gamete?
Each gamete contains only half the number of chromosomes (haploid).
p.15
Monohybrid and Dihybrid Crosses
What is the progeny distribution for the second cross?
176 yellow round, 0 yellow wrinkled, 60 green round, 0 green wrinkled.
p.10
Mendelian Genetics and Laws
What is the genotypic ratio for the 3:1 Monohybrid Ratio?
1 homozygous dominant : 2 heterozygotes : 1 homozygous recessive.
p.17
Non-Mendelian Genetics
What is a key characteristic of traits that do not follow Mendelian inheritance?
They do not give the expected 9:3:3:1 ratio in certain crosses.
p.12
Mendelian Genetics and Laws
How many phenotypes were found in the F2 generation?
Four phenotypes: two parental and two new combinations.
p.2
Key Genetic Terms and Definitions
What is a dominant allele?
An allele whose characteristics are expressed in the phenotype even in the presence of an alternative allele.
p.14
Mendelian Genetics and Laws
What is the purpose of a Dihybrid Test Cross?
To determine the genotype of an organism showing the dominant phenotypes for 2 traits.
p.5
Genetics and Inheritance Overview
What is the significance of traits at the population level?
Traits promote survival or reproduction and are important in evolution.
p.17
Non-Mendelian Genetics
What is epistasis?
When two genes interact to produce one phenotypic outcome.
p.28
Mendelian Genetics and Laws
What are the different modes of inheritance mentioned?
Autosomal Dominant, Autosomal Recessive, Sex-linked Dominant, Sex-linked Recessive.
p.4
Mendelian Genetics and Laws
What type of cells are formed after meiosis?
Gametes, which are haploid.
p.24
Sex Linkage and Inheritance Patterns
What are sex-linked traits?
Characteristics where the genes involved are found on the sex chromosome, and their inheritance depends on the sex of the organism.
p.16
Mendelian Genetics and Laws
What is the genotype of Variety B of flax?
aaBB (susceptible to race 22 and resistant to race 24).
p.5
Key Genetic Terms and Definitions
What role do proteins play in phenotype expression?
Proteins control phenotype as enzymes, pumps, transporters, motors, hormones, or structural elements.
p.29
Sex Linkage and Inheritance Patterns
Is it possible to find a tortoise-shell male cat?
No, because males have only one X chromosome.
p.1
Key Genetic Terms and Definitions
What is a locus?
The specific location of a gene on a chromosome.
p.6
Genetic Diagrams and Problem Solving
What must be true about gametes in terms of alleles?
Each gamete can only contain 1 copy of each gene (1 allele).
p.24
Sex Linkage and Inheritance Patterns
What is a key difference in F1 results between sex-linked and autosomal linked genes?
Reciprocal crosses give different F1 results for sex-linked genes, while they give the same F1 results for autosomal linked genes.
p.30
Environmental Effects on Phenotype
What is the fur color pattern of Himalayan rabbits?
White fur with black fur on the ears, noses, feet, and tails.
p.8
Mendelian Genetics and Laws
How many copies of the allele does each gamete carry?
Only 1 copy of the allele compared to the original cell.
p.13
Mendelian Genetics and Laws
How many different combinations of alleles are possible from a double heterozygote?
Four different combinations.
p.30
Environmental Effects on Phenotype
What happens to the enzyme tyrosinase at temperatures above 33°C?
The enzyme is denatured, resulting in light/white fur.
p.28
Genetics and Inheritance Overview
Why can't test-crosses be performed in humans?
Because we cannot perform test-cross, reciprocal cross, and back cross to determine genotypes.
p.28
Genetics and Inheritance Overview
What do shaded symbols in a pedigree represent?
Traits that are expressed.
p.30
Environmental Effects on Phenotype
Why are the extremities of Himalayan rabbits black?
Because the temperature is lower there than on the main body.
p.18
Codominance and Incomplete Dominance
What is the phenotypic ratio in the F2 generation of shorthorn cattle?
1 red : 2 roan : 1 white.
p.20
Multiple Alleles and Blood Groups
What are the three alleles for the ABO blood group?
I A, I B, and I O (or i).
p.20
Multiple Alleles and Blood Groups
What is the significance of blood group AB?
It is the universal recipient.
p.16
Mendelian Genetics and Laws
What is the genotype of Variety A of flax?
AABb (resistant to race 22 and susceptible to race 24).
p.8
Mendelian Genetics and Laws
What occurs in Anaphase II of meiosis?
Separation of sister chromatids.
p.26
Sex Linkage and Inheritance Patterns
What does it mean that both offspring are carriers in the first example?
They carry the allele for colourblindness but are phenotypically normal.
p.23
Sex Linkage and Inheritance Patterns
What are sex chromosomes?
Chromosomes that determine the sex of the organism.
p.23
Sex Linkage and Inheritance Patterns
What are autosomes?
Chromosomes that do not determine the gender.
p.1
Key Genetic Terms and Definitions
What is the difference between dominant and recessive alleles?
Dominant alleles express their traits even in the presence of a recessive allele, while recessive alleles only express their traits when homozygous.
p.13
Mendelian Genetics and Laws
What is present in each gamete according to Mendel's Law?
1 copy of the allele for each gene.
p.5
Genetics and Inheritance Overview
What are the four levels of the relationship between genotype and phenotype?
Molecular, Cellular, Organismal, and Population levels.
p.9
Mendelian Genetics and Laws
What is a test cross?
A cross between an organism with an unknown genotype showing dominant characteristics and a homozygous recessive individual.
p.5
Genetics and Inheritance Overview
How does the cellular level affect phenotype?
The presence of specific proteins affects the structure and biochemistry of the cell.
p.16
Mendelian Genetics and Laws
What are the dominant and recessive alleles for resistance to race 24?
B (dominant) for resistance and b (recessive) for susceptibility.
p.3
Environmental Effects on Phenotype
How can the phenotype be influenced?
By the genotype of the organism and environmental factors.
p.27
Sex Linkage and Inheritance Patterns
How can a couple with normal vision have a colorblind child?
Both parents could be carriers of the colorblind allele.
p.27
Sex Linkage and Inheritance Patterns
Is it possible for a colorblind girl to be born?
Yes, if both parents are carriers of the colorblind allele.
p.27
Sex Linkage and Inheritance Patterns
What happens in the absence of factor 8 in hemophiliacs?
It results in failure of blood to clot, causing slow and persistent bleeding.
p.27
Sex Linkage and Inheritance Patterns
What increases the frequency of hemophilia expression?
Inbreeding, such as in European royal families.
p.19
Mendelian Genetics and Laws
What is the significance of the F1 generation in this genetic cross?
They produce pink flowering offspring.
p.20
Multiple Alleles and Blood Groups
What does allele I O (or i) cause in terms of antigens?
No production of antigens on red blood cells.
p.6
Mendelian Genetics and Laws
What are the two laws discovered by Mendel?
Law of Segregation and Law of Independent Assortment.
p.6
Monohybrid and Dihybrid Crosses
What does a monohybrid cross involve?
The inheritance of one single pair of contrasting characters.
p.8
Mendelian Genetics and Laws
What happens during Anaphase I of meiosis?
Separation of homologous chromosomes.
p.10
Mendelian Genetics and Laws
What was the conclusion of the breeder regarding the black-spotted bitch's genotype?
The breeder concluded that the bitch was homozygous for the allele for black spots, but this conclusion is incorrect because the black-spotted bitch could be heterozygous.
p.2
Key Genetic Terms and Definitions
What is a gene?
A specific length of DNA that codes for a polypeptide and occupies a position on a chromosome known as a locus.
p.17
Non-Mendelian Genetics
What is the main idea of Non-Mendelian Genetics?
The inheritance pattern of many characteristics does not follow the ratios predicted by Mendel’s Laws.
p.15
Monohybrid and Dihybrid Crosses
What is the progeny distribution for the third cross?
223 yellow round, 247 yellow wrinkled, 75 green round, 86 green wrinkled.
p.23
Sex Linkage and Inheritance Patterns
What are sex-linked genes?
Genes found on the sex chromosomes, affected by the sex of the organism.
p.3
Key Genetic Terms and Definitions
What is a genotype?
The genetic makeup of an organism or set of alleles of an organism.
p.15
Genetic Diagrams and Problem Solving
What is the first step to determine the genotypes of the parents in the crosses?
Analyze the progeny results to identify dominant and recessive traits.
p.17
Non-Mendelian Genetics
What are some situations not covered by Mendel's Laws?
Not all organisms are diploid, one gene may have more than two alleles, some alleles do not show a dominant-recessive relationship, and alleles may not assort independently.
p.15
Key Genetic Terms and Definitions
Which alleles are dominant in the context of the given crosses?
Yellow and round are dominant traits.
p.9
Mendelian Genetics and Laws
Why is a homozygous recessive individual used in a test cross?
To ensure that all gametes from this individual contain a recessive allele, preventing masking of any recessive allele in the organism with the unknown genotype.
p.23
Sex Linkage and Inheritance Patterns
What is gametogenesis?
The formation of haploid gametes by diploid germ cells through meiosis.
p.28
Mendelian Genetics and Laws
What is an example of a trait studied through pedigrees?
Hypercholesterolemia, which is considered autosomal dominant.
p.12
Mendelian Genetics and Laws
What does independent assortment mean in genetics?
The alleles of different genes are inherited independently of each other.
p.28
Key Genetic Terms and Definitions
What does 'autosomal' mean in the context of inheritance?
The gene is carried on the autosomes or non-sex chromosomes.
p.3
Genetics and Inheritance Overview
What is the difference between sister chromatids and non-sister chromatids?
Sister chromatids are identical, while non-sister chromatids may carry different alleles.
p.18
Codominance and Incomplete Dominance
What is codominance?
The phenomenon in a heterozygote where both alleles are expressed in the phenotype.
p.29
Codominance and Incomplete Dominance
What are the alleles for fur color in cats?
B (black fur) and G (ginger fur), which are codominant.
p.5
Key Genetic Terms and Definitions
What is a gene?
A length of DNA that codes for a protein.
p.24
Sex Linkage and Inheritance Patterns
What must be indicated in sex-linkage studies?
The sex chromosomes (XX and XY) and the dominant and recessive alleles using appropriate superscript letters.
p.7
Mendelian Genetics and Laws
What is the outcome of gamete formation in a diploid organism?
Half of the gametes carry one allele, and the other half carry the other allele.
p.26
Sex Linkage and Inheritance Patterns
How can a man transmit a sex-linked trait to his grandson?
Through his daughter, as she can inherit the trait from her father.
p.2
Key Genetic Terms and Definitions
What does the term 'gene locus' refer to?
The position occupied by the gene on the chromosome.
p.26
Sex Linkage and Inheritance Patterns
What is the inheritance pattern of an X-linked trait typically observed?
Mother to son inheritance.
p.16
Mendelian Genetics and Laws
What does the presence of only one type of F1 hybrid indicate about the parental varieties?
They must be in the gene loci that determine specific resistance.
p.9
Mendelian Genetics and Laws
What is the purpose of a test cross?
To determine if an organism showing a dominant trait is homozygous dominant (AA) or heterozygous (Aa).
p.5
Genetics and Inheritance Overview
What occurs at the molecular level of genotype-phenotype relationship?
Gene transcription and translation leading to the production of a particular protein.
p.21
Multiple Alleles and Blood Groups
What phenotype does allele C produce in Himalayan rabbits?
Full coat color (all hair agouti).
p.1
Mendelian Genetics and Laws
What is the significance of meiosis in inheritance?
Meiosis produces gametes, which carry genetic information from one generation to the next.
p.30
Environmental Effects on Phenotype
What occurs when the temperature is below 33°C for Himalayan rabbits?
The enzyme is active, and melanin is produced, resulting in black (or brown) fur.
p.9
Mendelian Genetics and Laws
What are the two possible genotypes for an organism showing a dominant trait?
Homozygous dominant (AA) or heterozygous (Aa).
p.17
Non-Mendelian Genetics
What is sex linkage?
When a gene is located on a sex chromosome rather than an autosome.
p.3
Mendelian Genetics and Laws
What is the parental generation in genetic crosses?
The generation of individuals of different genotypes crossed to produce offspring.
p.3
Key Genetic Terms and Definitions
What does pure bred or true bred mean?
An organism that is homozygous for a particular characteristic or trait.
p.18
Codominance and Incomplete Dominance
How do heterozygotes appear in incomplete dominance?
They show an intermediate trait between the homozygous dominant and homozygous recessive phenotypes.
p.20
Multiple Alleles and Blood Groups
What is the definition of multiple alleles?
A trait controlled by a gene with 3 or more alleles, of which only 2 may occupy the same locus on homologous chromosomes.
p.20
Multiple Alleles and Blood Groups
What is the significance of blood group O?
It is the universal donor.
p.10
Mendelian Genetics and Laws
What determines the color of spots in Dalmatian dogs?
A gene with two alleles, where the black allele is dominant and the brown allele is recessive.
p.16
Mendelian Genetics and Laws
What does the F1 hybrid of the two varieties represent?
A double heterozygote (AaBb) resistant to both races of the fungus.
p.5
Mendelian Genetics and Laws
What does the dominant allele code for in flower color?
A functioning enzyme that converts a white pigment into a red pigment.
p.5
Mendelian Genetics and Laws
What is the result of the recessive allele in flower color?
It codes for a non-functional enzyme, resulting in white flowers.
p.30
Environmental Effects on Phenotype
How can the environment influence gene expression?
By affecting the organism's external and internal environment, such as hormones and metabolism.
p.8
Mendelian Genetics and Laws
What is the probability of each gamete being fertilized?
Each gamete has an equal probability of being fertilized by another gamete.
p.15
Monohybrid and Dihybrid Crosses
What is the progeny distribution for the fourth cross?
371 yellow round, 0 yellow wrinkled, 0 green round, 0 green wrinkled.
p.24
Sex Linkage and Inheritance Patterns
Where were sex-linked traits first discovered?
In Drosophila, when inheritance of some characteristics varied with the sex of the parent and offspring.
p.30
Environmental Effects on Phenotype
What allele do all Himalayan rabbits have?
The ch allele, which codes for a temperature-sensitive form of the enzyme tyrosinase.
p.1
Codominance and Incomplete Dominance
What is incomplete dominance?
A genetic scenario where the phenotype of heterozygotes is intermediate between the phenotypes of the two homozygotes.
p.13
Mendelian Genetics and Laws
What are the possible combinations of alleles from a double heterozygote?
RY, Ry, rY, ry in equal proportions.
p.17
Non-Mendelian Genetics
What is codominance?
A situation where alleles of a gene do not have a clear dominant-recessive relationship.
p.10
Mendelian Genetics and Laws
What are the possible outcomes when crossing unspotted and spotted plants?
Sometimes all offspring have unspotted petals, and sometimes half have spotted and half have unspotted petals.
p.12
Mendelian Genetics and Laws
What does Mendel's Second Law state?
Any one pair of characteristics may combine with either one of another pair.
p.3
Key Genetic Terms and Definitions
What is a phenotype?
All the characteristics of an individual that are expressed, including physical, physiological, and behavioral traits.
p.12
Mendelian Genetics and Laws
What happens during meiosis according to modern genetics?
The segregation of alleles of one gene pair is independent of the separation of alleles of other gene pairs.
p.30
Environmental Effects on Phenotype
What are the three phenotypes in a honey bee colony?
Queen bees, worker bees, and drones.
p.12
Mendelian Genetics and Laws
What is the ratio of round seeds to wrinkled seeds in the F2 generation?
9/16 round seeds to 7/16 wrinkled seeds.
p.3
Mendelian Genetics and Laws
What is the F2 generation?
The second filial generation produced by crossing two F1 organisms or by selfing.
p.14
Mendelian Genetics and Laws
Can you work out results for other test crosses for round yellow parents who are not double heterozygotes?
Yes, by determining the genotype of the round yellow parent and crossing it with the double homozygous recessive.
p.18
Codominance and Incomplete Dominance
What are the three phenotypes of sickle-cell anemia?
Homozygous normal, homozygous sickle-cell, and heterozygous condition.
p.7
Mendelian Genetics and Laws
What does the Law of Segregation state?
Only one of a pair of alleles can be represented in a single gamete.
p.24
Sex Linkage and Inheritance Patterns
What is a reciprocal cross?
A cross where the same genetic features are used but the sexes are reversed for each cross.
p.13
Mendelian Genetics and Laws
What does a double heterozygote carry?
Two pairs of homologous chromosomes, each carrying a different gene.
p.24
Sex Linkage and Inheritance Patterns
Why are reciprocal crosses important in sex-linkage studies?
They help evaluate the importance of parental sex on the inheritance of a given characteristic.
p.13
Mendelian Genetics and Laws
What results from the random arrangement of homologous chromosomes during Metaphase 1?
Different combinations of alleles in the gametes.
p.11
Dihybrid and Law of Independent Assortment
What traits did Mendel investigate in his genetic diagram?
Seed shape (round vs wrinkled) and seed color (green vs yellow).
p.10
Mendelian Genetics and Laws
What is the result of crossing a homozygous dominant organism with a homozygous recessive organism?
The 1:1 Monohybrid Test-Cross Ratio.
p.27
Sex Linkage and Inheritance Patterns
What must a female inherit to express colorblindness?
Two copies of the recessive alleles (homozygous recessive).
p.16
Mendelian Genetics and Laws
Why is resistance considered a dominant trait in this context?
Because the F1 is resistant to both race 22 and race 24.
p.27
Sex Linkage and Inheritance Patterns
What is the significance of reciprocal crosses in sex-linked inheritance?
They give different results in the F1 generation.
p.11
Dihybrid and Law of Independent Assortment
Which alleles are dominant in Mendel's investigation?
R is dominant over r and Y is dominant over y.
p.30
Environmental Effects on Phenotype
What experiment did Sturtevant conduct to demonstrate color change in Himalayan rabbits?
He shaved a small area of fur and applied ice packs, resulting in black fur regrowth.
p.9
Multiple Alleles and Blood Groups
What does Rh+ and Rh- signify in blood types?
Rh+ indicates blood with the Rhesus factor, while Rh- indicates blood without the Rhesus factor.
p.3
Mendelian Genetics and Laws
What is the F1 generation?
The first filial generation produced by crossing two parental stocks.
p.19
Key Genetic Terms and Definitions
What are the genotypes of the red and white flowered snapdragons?
Red: C_R C_R; White: C_W C_W.
p.19
Mendelian Genetics and Laws
What is the phenotypic ratio of the F2 generation from pink snapdragons?
1 red : 2 pink : 1 white.
p.18
Codominance and Incomplete Dominance
How do heterozygotes appear in codominance?
They show the characteristics of both alleles.
p.29
Codominance and Incomplete Dominance
How many classes of coat color would you find in female cats?
Two classes: black and ginger, plus tortoise-shell.
p.26
Sex Linkage and Inheritance Patterns
What are the phenotypes of the F1 generation from the first example?
Female with normal vision and Male with normal vision.
p.11
Dihybrid and Law of Independent Assortment
Give an example of Dihybrid Inheritance.
Tall plants with pink flowers vs Short plants with white flowers.
p.10
Mendelian Genetics and Laws
What is the phenotypic ratio obtained when both parents are homozygous for a trait in monohybrid inheritance?
The 3:1 Monohybrid Ratio.
p.11
Dihybrid and Law of Independent Assortment
What does the Law of Independent Assortment state?
The inheritance of 2 different characters is independent of each other.
p.21
Multiple Alleles and Blood Groups
How can offspring with blood group O be produced from parents with blood groups A and B?
Both parents must be heterozygous, contributing one IO allele each.
p.17
Non-Mendelian Genetics
What did Mendel's experimental work primarily involve?
Crossing pea plants that displayed complete dominance.
p.11
Dihybrid and Law of Independent Assortment
What are the alleles for round and wrinkled seeds?
R = allele for round seed, r = allele for wrinkled seed.
p.10
Mendelian Genetics and Laws
What is the genotypic ratio of the offspring when a heterozygote is crossed with a homozygous recessive organism?
1 heterozygote : 1 homozygous recessive.
p.3
Key Genetic Terms and Definitions
What does homozygous mean?
A diploid condition where both alleles for a particular gene are identical.
p.10
Mendelian Genetics and Laws
What happens when two plants with spotted petals are crossed?
The offspring always have spotted petals.
p.23
Sex Linkage and Inheritance Patterns
What is the gamete formation ratio in humans?
1:1, indicating equal probability of having a boy or a girl.
p.17
Non-Mendelian Genetics
What does multiple alleles refer to?
A single gene having more than two different alleles.
p.20
Multiple Alleles and Blood Groups
What is an example of multiple alleles in humans?
The human blood group ABO.
p.20
Multiple Alleles and Blood Groups
Can blood groups prove paternity?
No, but they can show that an individual could not possibly be the father.
p.23
Sex Linkage and Inheritance Patterns
What is the heterogametic sex?
The sex that produces two types of gametes (e.g., males with XY genotype).
p.2
Key Genetic Terms and Definitions
What is a recessive allele?
An allele whose characteristics are only expressed in the phenotype in the presence of another identical allele (homozygous condition).
p.5
Genetics and Inheritance Overview
What determines the traits of an organism at the organismal level?
The characteristics of cells, such as the production of pigments.
p.14
Mendelian Genetics and Laws
What type of organism is used in a Dihybrid Test Cross?
A double homozygous recessive organism.
p.9
Monohybrid and Dihybrid Crosses
What is an example of monohybrid inheritance involving fruit flies?
Long wing vs. vestigial wing.
p.2
Key Genetic Terms and Definitions
What is an example of a dominant and recessive allele in plants?
Allele P for purple stem is dominant over allele p for green stem.
p.17
Non-Mendelian Genetics
What is polygenic inheritance?
A trait resulting from multiple genes, each potentially having multiple alleles, with phenotypic outcomes due to the additive effects of these alleles.
p.27
Sex Linkage and Inheritance Patterns
What is hemophilia and what causes it?
A sex-linked trait due to the inability to produce clotting factor 8.
p.27
Sex Linkage and Inheritance Patterns
How can hemophiliacs lead a near-normal life?
By receiving factor 8 through blood transfusions.
p.19
Genetic Diagrams and Problem Solving
What are the genotypes of the F2 generation from the pink snapdragons?
C_R C_R, C_R C_W, C_W C_W.
p.3
Key Genetic Terms and Definitions
What is a heterozygous organism?
An organism with different alleles of a gene present.
p.27
Sex Linkage and Inheritance Patterns
How does the phenotypic ratio differ in sex-linked traits?
It differs in male and female progeny of a cross.
p.1
Environmental Effects on Phenotype
How can the environment affect phenotype?
Environmental factors like diet and temperature can influence the expression of traits.
p.27
Sex Linkage and Inheritance Patterns
What type of inheritance pattern is observed in colorblindness?
Criss-cross inheritance (mother to son).
p.27
Sex Linkage and Inheritance Patterns
In X-linked recessive characteristics, which sex is more commonly affected?
Males are more commonly affected than females.
p.14
Mendelian Genetics and Laws
What are the phenotypes involved in the example provided?
Round, yellow; round, green; wrinkled, yellow.
p.30
Environmental Effects on Phenotype
What is the genetic composition of queen and worker bees compared to drones?
Queens and workers are diploid females, while drones are haploid males.
p.9
Mendelian Genetics and Laws
If a plant is heterozygous, what can it pass to its offspring?
Either the dominant or recessive allele.
p.28
Genetics and Inheritance Overview
What is a key clue to interpreting pedigrees?
Studying the line of descent to deduce gene inheritance.
p.19
Genetic Diagrams and Problem Solving
What gametes are produced by the red and white snapdragons during meiosis?
Red produces all C_R; White produces all C_W.
p.9
Mendelian Genetics and Laws
If a plant is homozygous dominant, what will it pass to its offspring?
The dominant allele (P) to all offspring.
p.12
Mendelian Genetics and Laws
What is the ratio of yellow seeds to green seeds in the F2 generation?
6/16 yellow seeds to 2/16 green seeds.
p.28
Genetics and Inheritance Overview
What is a limitation of studying F1 and F2 generations in humans?
They are too small for statistical analysis.
p.14
Mendelian Genetics and Laws
What is the expected Dihybrid Test Cross ratio when crossing RrYy with rryy?
1 round yellow : 1 round green : 1 wrinkled yellow : 1 wrinkled green.
p.3
Genetics and Inheritance Overview
What are homologous chromosomes?
Chromosomes that are similar but not identical, sharing the same length, size, and position of centromere.
p.18
Codominance and Incomplete Dominance
What is incomplete dominance?
A case where neither allele is completely dominant, resulting in an intermediate phenotype in the F1 offspring.
p.18
Codominance and Incomplete Dominance
What is an example of incomplete dominance in plants?
Flower color in Antirrhinum (snapdragon).
p.20
Multiple Alleles and Blood Groups
What is the gene locus for the ABO blood group represented by?
The letter I (isohaemagglutinin).
