12 Inheritance I Notes 2024

A sex-linked recessive trait characterized by the inability to see red and green.

No, fathers pass their X chromosome (with the trait) to daughters and the Y chromosome to sons.

Gregor Mendel.

Tt.

Homozygous and heterozygous.

The fusion of haploid gametes during fertilization.

Examples of crosses between rabbits with different coats.

The behavior of chromosomes.

Glucose 6-phosphate deficiency.

It creates different combinations of alleles in the organism.

The daughter will become a carrier if her other X chromosome carries a normal allele.

Because the alleles are located on the sex chromosomes, and gender itself is a phenotypic difference.

The alleles occupy the same position on separate chromosomes.

All possible outcomes of a genetic cross.

3:1.

X^B X^G.

Green and yellow; round and wrinkled.

Yellow round and green wrinkled.

Inheritance of 2 pairs of contrasting characteristics simultaneously (i.e., 2 genes).

Genotype determines the traits expressed in the phenotype.

1:1:1:1.

Because it produces some functional protein in heterozygous cells, which is usually sufficient for the desired effect.

A child inherits one allele from each parent, determining their blood group.

A genetic scenario where both alleles in a heterozygote are fully expressed.

The sex that produces only one kind of gamete (e.g., females with XX genotype).

Y = allele for yellow seed, y = allele for green seed.

A (dominant) for resistance and a (recessive) for susceptibility.

Rabbits.

Crossing over and independent assortment.

From their mothers.

A sex-linked recessive trait.

They must be written on the sex chromosome.

Red-green color blindness and hemophilia.

A genetic cross involving two traits.

138 yellow round, 143 yellow wrinkled, 137 green round, 142 green wrinkled.

9:3:3:1.

Male: T, t; Female: T, t.

All round and yellow, indicating these traits are dominant.

Alternative forms of a gene, each with a slightly different nucleotide sequence, coding for different forms of the same trait.

XcXc.

Two alleles, one on each of the pair of homologous chromosomes.

A diploid organism.

Men have no corresponding allele on the Y chromosome to mask the effect of the recessive allele on the X chromosome.

The X chromosome carries many such genes, while the Y chromosome has very few.

Genotypes and phenotypes.

Two classes: black and ginger.

IAIO (blood group A) and IBIO (blood group B).

Each gamete contains only half the number of chromosomes (haploid).

176 yellow round, 0 yellow wrinkled, 60 green round, 0 green wrinkled.

50%.

1 homozygous dominant : 2 heterozygotes : 1 homozygous recessive.

They must be co-related.

They do not give the expected 9:3:3:1 ratio in certain crosses.

Four phenotypes: two parental and two new combinations.

An allele whose characteristics are expressed in the phenotype even in the presence of an alternative allele.

A ratio of 3:1.

C > Cch > Ch > c.

To determine the genotype of an organism showing the dominant phenotypes for 2 traits.

Traits promote survival or reproduction and are important in evolution.

When two genes interact to produce one phenotypic outcome.

Autosomal Dominant, Autosomal Recessive, Sex-linked Dominant, Sex-linked Recessive.

Coat color.

Gametes, which are haploid.

Characteristics where the genes involved are found on the sex chromosome, and their inheritance depends on the sex of the organism.

aaBB (susceptible to race 22 and resistant to race 24).

Proteins control phenotype as enzymes, pumps, transporters, motors, hormones, or structural elements.

No, because males have only one X chromosome.

The genotype.

The specific location of a gene on a chromosome.

Each gamete can only contain 1 copy of each gene (1 allele).

Reciprocal crosses give different F1 results for sex-linked genes, while they give the same F1 results for autosomal linked genes.

White fur with black fur on the ears, noses, feet, and tails.

Only 1 copy of the allele compared to the original cell.

Four different combinations.

The enzyme is denatured, resulting in light/white fur.

Because we cannot perform test-cross, reciprocal cross, and back cross to determine genotypes.

Traits that are expressed.

Because the temperature is lower there than on the main body.

XY.

RrYy.

1 red : 2 roan : 1 white.

I A, I B, and I O (or i).

It is the universal recipient.

Yy.

Law of Segregation.

AABb (resistant to race 22 and susceptible to race 24).

T (dominant allele).

Separation of sister chromatids.

They carry the allele for colourblindness but are phenotypically normal.

Chromosomes that determine the sex of the organism.

Chromosomes that do not determine the gender.

Dominant alleles express their traits even in the presence of a recessive allele, while recessive alleles only express their traits when homozygous.

1 copy of the allele for each gene.

Molecular, Cellular, Organismal, and Population levels.

C, Cch, Ch, and c.

A cross between an organism with an unknown genotype showing dominant characteristics and a homozygous recessive individual.

The presence of specific proteins affects the structure and biochemistry of the cell.

B (dominant) for resistance and b (recessive) for susceptibility.

CchCch or CchCh.

By the genotype of the organism and environmental factors.

Both parents could be carriers of the colorblind allele.

Yes, if both parents are carriers of the colorblind allele.

It results in failure of blood to clot, causing slow and persistent bleeding.

Inbreeding, such as in European royal families.

They produce pink flowering offspring.

No production of antigens on red blood cells.

Law of Segregation and Law of Independent Assortment.

The inheritance of one single pair of contrasting characters.

Separation of homologous chromosomes.

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.

A specific length of DNA that codes for a polypeptide and occupies a position on a chromosome known as a locus.

The inheritance pattern of many characteristics does not follow the ratios predicted by Mendel’s Laws.

223 yellow round, 247 yellow wrinkled, 75 green round, 86 green wrinkled.

Genes found on the sex chromosomes, affected by the sex of the organism.

A 9:3:3:1 ratio.

The genetic makeup of an organism or set of alleles of an organism.

Analyze the progeny results to identify dominant and recessive traits.

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.

Yellow and round are dominant traits.

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.

The formation of haploid gametes by diploid germ cells through meiosis.

Hypercholesterolemia, which is considered autosomal dominant.

The alleles of different genes are inherited independently of each other.

The gene is carried on the autosomes or non-sex chromosomes.

0.50 (50%).

Sister chromatids are identical, while non-sister chromatids may carry different alleles.

The phenomenon in a heterozygote where both alleles are expressed in the phenotype.

Hb A Hb S.

B (black fur) and G (ginger fur), which are codominant.

3:1.

A length of DNA that codes for a protein.

The sex chromosomes (XX and XY) and the dominant and recessive alleles using appropriate superscript letters.

Half of the gametes carry one allele, and the other half carry the other allele.

tt.

Through his daughter, as she can inherit the trait from her father.

The position occupied by the gene on the chromosome.

Mother to son inheritance.

They must be in the gene loci that determine specific resistance.

To determine if an organism showing a dominant trait is homozygous dominant (AA) or heterozygous (Aa).

Gene transcription and translation leading to the production of a particular protein.

Full coat color (all hair agouti).

Meiosis produces gametes, which carry genetic information from one generation to the next.

The enzyme is active, and melanin is produced, resulting in black (or brown) fur.

Homozygous dominant (AA) or heterozygous (Aa).

When a gene is located on a sex chromosome rather than an autosome.

The generation of individuals of different genotypes crossed to produce offspring.

cc.

The child must be male.

An organism that is homozygous for a particular characteristic or trait.

They show an intermediate trait between the homozygous dominant and homozygous recessive phenotypes.

A trait controlled by a gene with 3 or more alleles, of which only 2 may occupy the same locus on homologous chromosomes.

It is the universal donor.

Inheritance.

XcY.

A gene with two alleles, where the black allele is dominant and the brown allele is recessive.

A double heterozygote (AaBb) resistant to both races of the fungus.

A functioning enzyme that converts a white pigment into a red pigment.

1:1:1:1 (AB:A:B:O).

It codes for a non-functional enzyme, resulting in white flowers.

By affecting the organism's external and internal environment, such as hormones and metabolism.

Each gamete has an equal probability of being fertilized by another gamete.

371 yellow round, 0 yellow wrinkled, 0 green round, 0 green wrinkled.

In Drosophila, when inheritance of some characteristics varied with the sex of the parent and offspring.

The ch allele, which codes for a temperature-sensitive form of the enzyme tyrosinase.

A genetic scenario where the phenotype of heterozygotes is intermediate between the phenotypes of the two homozygotes.

RY, Ry, rY, ry in equal proportions.

A situation where alleles of a gene do not have a clear dominant-recessive relationship.

Sometimes all offspring have unspotted petals, and sometimes half have spotted and half have unspotted petals.

Any one pair of characteristics may combine with either one of another pair.

All the characteristics of an individual that are expressed, including physical, physiological, and behavioral traits.

The segregation of alleles of one gene pair is independent of the separation of alleles of other gene pairs.

ChCh or Chc.

Queen bees, worker bees, and drones.

9/16 round seeds to 7/16 wrinkled seeds.

The second filial generation produced by crossing two F1 organisms or by selfing.

Yes, by determining the genotype of the round yellow parent and crossing it with the double homozygous recessive.

Incomplete dominance.

Homozygous normal, homozygous sickle-cell, and heterozygous condition.

Alleles I A and I B.

Only one of a pair of alleles can be represented in a single gamete.

Anaphase I.

TT.

A cross where the same genetic features are used but the sexes are reversed for each cross.

Two pairs of homologous chromosomes, each carrying a different gene.

They help evaluate the importance of parental sex on the inheritance of a given characteristic.

Different combinations of alleles in the gametes.

Seed shape (round vs wrinkled) and seed color (green vs yellow).

The 1:1 Monohybrid Test-Cross Ratio.

Two copies of the recessive alleles (homozygous recessive).

Because the F1 is resistant to both race 22 and race 24.

The study of pedigrees.

They give different results in the F1 generation.

R is dominant over r and Y is dominant over y.

1:1.

One allele of each gene.

By a lower case letter.

He shaved a small area of fur and applied ice packs, resulting in black fur regrowth.

Rh+ indicates blood with the Rhesus factor, while Rh- indicates blood without the Rhesus factor.

The first filial generation produced by crossing two parental stocks.

rryy.

Red: C_R C_R; White: C_W C_W.

1 red : 2 pink : 1 white.

They show the characteristics of both alleles.

Hb A Hb A.

Two classes: black and ginger, plus tortoise-shell.

Female with normal vision and Male with normal vision.

YyRr.

Tall plants with pink flowers vs Short plants with white flowers.

The 3:1 Monohybrid Ratio.

The inheritance of 2 different characters is independent of each other.

Both parents must be heterozygous, contributing one IO allele each.

Crossing pea plants that displayed complete dominance.

R = allele for round seed, r = allele for wrinkled seed.

1 heterozygote : 1 homozygous recessive.

A diploid condition where both alleles for a particular gene are identical.

The offspring always have spotted petals.

1:1, indicating equal probability of having a boy or a girl.

A single gene having more than two different alleles.

XX.

The human blood group ABO.

No, but they can show that an individual could not possibly be the father.

Xc and Xc.

The sex that produces two types of gametes (e.g., males with XY genotype).

XcYC and XcY.

An allele whose characteristics are only expressed in the phenotype in the presence of another identical allele (homozygous condition).

The characteristics of cells, such as the production of pigments.

By an upper case letter.

A double homozygous recessive organism.

Long wing vs. vestigial wing.

Allele P for purple stem is dominant over allele p for green stem.

A trait resulting from multiple genes, each potentially having multiple alleles, with phenotypic outcomes due to the additive effects of these alleles.

A sex-linked trait due to the inability to produce clotting factor 8.

By receiving factor 8 through blood transfusions.

C_R C_R, C_R C_W, C_W C_W.

An organism with different alleles of a gene present.

It differs in male and female progeny of a cross.

Environmental factors like diet and temperature can influence the expression of traits.

Criss-cross inheritance (mother to son).

Punnett square.

Males are more commonly affected than females.

Round, yellow; round, green; wrinkled, yellow.

Queens and workers are diploid females, while drones are haploid males.

Either the dominant or recessive allele.

Studying the line of descent to deduce gene inheritance.

Red produces all C_R; White produces all C_W.

AB blood group.

3 different alleles.

The dominant allele (P) to all offspring.

6/16 yellow seeds to 2/16 green seeds.

They are too small for statistical analysis.

1 round yellow : 1 round green : 1 wrinkled yellow : 1 wrinkled green.

Chromosomes that are similar but not identical, sharing the same length, size, and position of centromere.

Pink.

A case where neither allele is completely dominant, resulting in an intermediate phenotype in the F1 offspring.

Flower color in Antirrhinum (snapdragon).

The letter I (isohaemagglutinin).