Answer: Option B. -> False
:
B
While lack of oxygen is the end cause for death in haemophilia, the reason for lack of oxygen is the continuous loss of blood due to failure of blood clotting.In this disease, a single protein that is a part of the cascade of proteins involved in the clotting of blood is affected. Due to this, in an affected individual a simple cut will result in non-stop bleeding.

Answer: Option B. -> inheritance
:
B
Inheritance is the process by which characters are passed on from parents to offspring. It is the basis of heredity.
Genetic inheritance occurs due to the presence of genetic material in the form ofDNA,being passed fromparents to their offspring. When organisms reproduce,all the information for growth, survival, and reproduction for the next generation is found in the DNA which is passed down from the parent generation.

Answer: Option A. -> Autosomal recessive
:
A
From the chart we can see that female parentis carrier for the disease. The male parent is unaffected. Let us denote the allele as 'F'. The mother's genotype will be Ff since she is a carrier. The father can be either FF or Ff. In the first generation, we see that none of the offsprings are affected. Out of five offsprings, three are carriers and two areunaffected. This indicates that the father's genotype is FF. This also tells us that the gene is recessive. If it was a dominant trait, it would have showed in the offsprings. Also, both male and female children are carriers, indicating that the trait is not sex linked. That means the pedigree chart shows a autosomal recessive disorder. In the second generation again, we see that in one family father is a carrier and mother is unaffected. For these parents one daughter is a carrier (Ff) and one daughter is unaffected (FF). From this we can make out that father is heterozygous (Ff) for the trait and the mother is homozygous dominant (FF). For the second family, we see that both mother and father are carriers, so both of them are heterozygous for the trait (Ff). Out of the five offsprings,two are carriers (one boy and one girl), two are affected (one boy and one girl) and one boy is unaffected. Thus, we can infer that the trait is autosomal recessive in nature.

Answer: Option B. -> False
:
B
DNAmolecules arepackaged into thread-like structures calledchromosomes. Genes are segments of DNA arranged along a chromosome. A single chromosome can have hundreds or even thousands of genes. Chromosomes are made up of repeating units of genes.

Answer: Option A. -> Honey bee
:
A
Each colony of honey bee contains three adult castes: egg-laying queen, sperm-producing male drones and non-reproductive female workers.During the winter season, a queen forms a new colony by laying eggs within each cell inside a honeycomb. Fertilized eggs hatch into female workerbees, while unfertilized eggs become drones orhoney beemales.

Answer: Option A. -> True
:
A
Amutationis a change that occurs in our DNA sequence, either due to mistakes when the DNA is copied or as the result of environmental factors such as UV light and cigarette smoke, etc. Gene mutations lead to creation of new alleles and thus different traits.

Answer: Option B. -> Very dark and very fair
:
B
Considering $\frac{A}{a},\frac{B}{b}and\frac{C}{c}$ as the three genes responsible for skin color inheritance, the dominant alleles A, B and C represent greater melanin production and the recessive alleles a, b and c represent less melanin production. Thus, a person with the genotype AABBCC would be very dark, while a person with the genotype aabbcc would be very fair.

Answer: Option B. -> X-linked dominant
:
B
From the chart we can see that the male parent is affected while the female parent is unaffected. In the first generation, out of four children, both daughters are affected . X-linked dominant disorders are caused by mutations in genes on the X chromosome, one of the two sex chromosomes in each cell. In females (who have two X chromosomes), a mutation in one of the two copies of the gene is sufficient to cause the disorder. In males (who have only one X chromosome), a mutation in the only copy of the gene causes the disorder. The daughters by default, inherit one X-chromosome from the mother and one X-chromosome from the father. Moreover,in the chart, we can see that father is affected, which means he has the defective allele on the X-chromosome which he has passed on to his daughters. In the second generation again we see that, both affected mothers, pass on the disease to all their children, daughters and sons both. This is possible only when the X-linked defective allele is dominant. If the X-linked defective allele was recessive, daughters wouldnot have been affected in this scenario.

Answer: Option C. -> Dominant over
:
C
Morgan started his work with the fruit fly around the year 1904. He was breeding fruit flies for his research. Normally in Drosophila, the color of the eye is red.Thomas Hunt Morgan, studying the fruit fly Drosophila melanogaster, detected a mutant male fly, one that differed strikingly from normal flies of the same species: its eyes were white instead of red.He first crossed the mutant male to a normal female to see if red or white eyes were dominant. All of the $F_1$ progeny had red eyes, so Morgan concluded that red eye color was dominant over white.

Answer: Option A. -> Round yellow seeds
:
A

• Yellow colour of pea seeds is dominant over green color and round shape of pea seeds is dominant over wrinkled ones.


• Across between pure yellow round seeded plants (YYRR) and green wrinkled seeded plants (yyrr) would yield heterozygous plants with yellow round seeds (YyRr) in the ${\text{F}}_1$ generation.