Sex determination in birds is different from that in humans. The sex chromosomes in birds are called Z and W, because males have two of the same chromosome (ZZ), whereas females have two different chromosomes (ZW). There is a Z-linked allele in some birds that causes the death of the embryo when the normal dominant allele is not present. What would be the sex ratio in the living offspring of a cross between a male heterozygous for the lethal allele and a normal female? A) What are the genotypes of the parents? Male____ Female____ B)  Which gametes would each form? Male____ Female____   C) Draw your Punnett square below and determine the sex ratios of living offspring.

Q: In Drosophila, a fully heterozygous female with the X-linked recessive genes a, b, and c (not…

A: A fully heterozygous female with x linked gene a, b, c was mated with male a, b, c. Parental cross -…

Q: In female mamals, X chromosome inactivation often leads to phenotypic mosaicism. Assume that black…

A: Coat color in animals is controlled by either autosomal or sex-linked genes. Coat color is a…

Q: The inheritance of colour in domestic pigeons involves several genes. The dominance hierarchy of…

A: The combination of sex chromosomes are often used to determine the sex of an embryo. In case of…

Q: In humans, brown eyes (B) are dominant over blue. A brown eyed man marries a blue-eyed (b) woman and…

A: Genes are the functional unit of heredity. It carries information that is transferred from one…

Q: In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A recessive…

A: Lethal gene is a condition in which the reccessive gene containig species can not survie and leads…

Q: Red-green color blindness is a sex-linked recessive trait in humans. Two people with normal color…

A: The red green color blindness trait is encoded by the gene present on X chromosome.

Q: Xg is an antigen found on red blood cells. This antigen is caused by an Xlinked allele (Xa) that is…

A: The X alleles are present in the X chromosome, which is a sex-chromosome. The number of X…

Q: Blank #4: For song pitch, what is the genotype of a high-pitched female bird? Blank #5: What is the…

A: Blank 4 - sex-limited means a trait which is confined or visible only within one sex .  So ,…

Q: In German cockroaches, bulging eyes (bu) are recessive to normal eyes (bu+), and curved wings (cv)…

A: Answer is e.bu cv+

Q: As shown in the Punnett square below, one variety of deafness is caused by an autosomal recessive…

A: An autosomal recessive disorder is defined as a condition or state in which two copies of an…

Q: Coat color in cats is determined by genes at several different loci. At one locus on the X…

A: An organism has phenotype and genotype. Phenotype is the observable characteristics and genotype is…

Q: On average, what fraction of the genome in the pairs of humans would be exactly the same if no…

A: 1. The father donates one-half of his genome to his child. Therefore, the similarity between the…

Q: For an X-linked recessive allele, what proportion of female offspring will be carriers in the cross…

A: X - linked recessive allele -  This type of allele is caused due to genetic mutation in the gene. In…

Q: In humans, brown eyes (B) are dominant over blue (b)*. A brown-eyed man marries a blue-eyed woman…

A: The gametes are produced as a result of meiosis in diploid parent cell.

Q: In a species of fly, smooth wings (W) are dominant to wrinkled wings (w) and red bodies (R) are…

A: Introduction : The given data represents two point cross.  A two point test cross is done…

Q: In a population of martians the hair color (H= purple or h=green) and eye-color (E=red or e=yellow)…

A: The genotype of the male’s father: HE/HEThe genotype of the male’s mother: he/heThe genotype of the…

Q: Butterflies have an X-Y sex-determination system that is different from that of flies or humans.…

A: -The butterfly shown has a completely unique pattern of colors because o a special trait- it has two…

Q: The inheritance of colour in domestic pigeons involves several genes. The dominance hierarchy of…

A: These colours are carried on the Z sex chromosome.  Unlike humans, female pigeons have two different…

Q: A researcher hypothesizes that, in mice, two autosomal dominant traits, trait Q and trait R, are…

A: In living organisms, the differences in the specific traits are due to the presence of two versions…

Q: Drosophila have XX/XY sex determination systems just like mammals. In Drosophila, loci for both eye…

A: Most creatures and many plants show sexual dimorphism; at the end of the day, an individual can be…

Q: In grasshoppers, rosy body color is caused by a recessive mutation; the wild-type body color is…

A: The phenotype of an organism is depends on the expression of the gene. Usually a gene has two…

Q: What would be the genotypic and phenotypic outcome if each parent was self-fertilized?

A: Genotype is refer to a gene or set of genes that leads to a single trait. Phenotype is refers to the…

Q: In humans, brown eyes (B) are dominant over blue. A brown eyed man marries a blue-eyed (b) woman and…

A: Brown eyes (B) = Dominant  Blue eye (b)= Recessive

Q: Skin color in humans is determined by polygenic inheritance, which means the more dominant alleles…

A: Polygenic inheritance: - in this inheritance, more than one genes control the single characteristic.…

Q: Which of the following findings supports the fact that the presence of the Y-chromosome rather than…

A: In mammals the sex chromosomes are X and Y. The genotype for a normal female is XX and that of…

Q: Brachydactyly is a genetic condition in which the fingers are abnormally short in heterozygotes.…

A: Alleles are the alternative forms of a gene that are located on the same locus of a homologous…

Q: On average, what proportion of the genome in the following pairs of humans would be exactly the same…

A: Chromosomes are thread-like structures comprised of two strands of DNA. Humans contain 23 pairs of…

Q: Honey Bees are unusual in that male bees (drones) have only one copy of each gene, while female bees…

A: The genotype is defined as a part of the genomic constitution of an organism that controls different…

Q: Which of the following is the genotype for a female with a yellow body and red eyes, who is…

A: Alleles are the different forms of a gene. The genotype of two same alleles is called homozygous…

Q: In rabbits, the homozygous CC is normal, Cc results in very long legs, and cc results in very short…

A: Given,  CC - normal leg length Cc - very long legs cc - very short legs BB - black fur Bb - brown…

Q: brown eyes (B) are dominant over blue. A brown eyed man marries a blue-eyed (b) woman and they have…

A: The organisms with two same alleles at a genetic locus is called as a homozygote. The organism with…

Q: Red-green color blindness is a recessive trait in humans.  The locus is on the X chromosome.  If a…

A: Answer. Red-green color blindness is sex- linked recessive defect in which human beings are unable…

Q: Tightly curled hair is caused by a dominant autosomal gene in humans. This trait is rare among…

A: if they are homozygous dominant then CC. if they are heterozygous dominant then Cc. if they are with…

Q: In German cockroaches, bulging eyes (bu) are recessive to normal eyes (bu+) and curved wings (cv)…

A: Introduction Dihybrid cross deals with two traits controlled by two pair alleles such as Bulging…

Q: Human females have two X chromosomes (XX); males have one X and one Y chromosome (XY). a. With…

A: Male has two types of chromosomes are X and Y whereas females have two chromosomes both are X and…

Q: Honeybees are unusual in that male bees (drones) have only onecopy of each gene, but female bees…

A: A gene is a unit of genetic material and alleles are the alternative form of genes present on the…

Q: In organisms with the ZZ-ZW sex-determining system, from which of the following possibilities can a…

A: Introduction: In ZZ-ZW system of sex determination, female carries two different gametes i.e., ZW…

Q: The eye ring color in wood ducks is under the control of a single, sex linked gene.  The dominant…

A: Sex determination - Sex determination is defined as the biological system which is used to determine…

Q: In the fruit fly, Drosophila, eye color is a sex-linked recessive trait located on the X chromosome.…

A: Inheritance is the process of transmitting the traits from parent to offspring. Traits of an…

Q: In mice, dwarfism is caused by an X-linked recessive allele, and pink coat is caused by an autosomal…

A: According to the given question, In mice, dwarfism is caused by an X-linked recessive allele, and…

Q: In organisms with the ZZ-ZW sex-determining system, from which of the following possibilities can a…

A: The Sex-determination system helps to determine sexual characteristics in an organism. Sex…

Q: A certain type of congenital deafness in humans is caused by a rare autosomal (not X-linked)…

A: DNA is the genetic material in most living organisms. It is the information hub of the cell that…

Q: Gene S controls the sharpness of spines in a type of cactus. Cactuses with the dominant allele have…

A: Cactus  Cactus are the plant that grows in water scarcity conditions. They are plant from the group…

Q: 45

A: Genes are the functional units of heredity. It contains information that is transferred from one…

Q: Mating took place between males and females of a fruit fly, and individuals appeared With the…

A: Introduction: In Drosophila, sex determination is determined by a balance of female determinants on…

Q: In rabbits, white fur colour (W) is dominant over black fur colour (w), and upright ears (U) are…

A: Given, white fur colour (W) is dominanant over black fur colour (w) in rabbits, and, Upright ears…

Q: In Drosophila, the recessive allele for forked bristles is X-linked, and the recessive allele for…

A: In a dihybrid cross, a pattern of inheritance of two different characteristics can be understood. To…

Q: The presence of horns on satyrs is produced by a sex-influenced autosomal gene that is dominant in…

A: Sex-influenced traits are the characteristic of autosomal traits that are influenced by sex. If a…

Q: In elegans, lon-2 and unc-2 are recessive mutations that are 8 map units apart on the X chromosome.…

A: A map unit is defined as the distance between two linked gene pairs where 1% of the products of…

Mitochondrial Mutations

A mitochondrion is a cellular organelle that serves as the site for cellular respiration and energy production (ATP or Adenosine Triphosphate). It is a double-membrane-bound organelle and is only present in eukaryotic cells.