31. In incomplete dominance__.
[A] Phenotype of both alleles is expressed
[B] Phenotype of only one allele is expressed
[C] Phenotype of neither of the alleles are expressed
[D] Phenotype of both alleles is partially expressed
Show Answer
Correct Answer: D [Phenotype of both alleles is partially expressed]
Notes:
In incomplete dominance, the phenotype of both alleles is partially expressed.
32. Restriction enzymes were discovered by?
[A] Smith and Nathans
[B] Alexander Fleming
[C] Berg
[D] None of these
Show Answer
Correct Answer: A [Smith and Nathans]
Notes:
Restriction enzymes were discovered by Smith and Nathans. Proteins produced by bacteria that cleave DNA at specific sites along the molecule are called restriction enzymes.
33. Which of the following diseases are not caused by smog?
[A] Breathing problem
[B] Throat cancer
[C] Skin cancer
[D] Rickets
Show Answer
Correct Answer: D [Rickets]
Notes:
Rickets is the softening and weakening of bones in children, usually because of an extreme and prolonged vitamin D deficiency. Vitamin D promotes the absorption of calcium and phosphorus from the gastrointestinal tract.
34. Eyes must be removed within ___ hours after the death for eye donation:
[A] 6
[B] 8
[C] 12
[D] 24
Show Answer
Correct Answer: A [6]
Notes:
Organ donation is the process of donating organs or biological tissue to a living recipient, who is in need of a transplant. The eyes of a dead person can be used only if they are taken out within 6 hrs of death. Only corneal blinds can be benefitted through this process not other Blinds.
35. Which part becomes modified as the tusk of elephant?
[A] Premolar
[B] Second incisor
[C] Molar
[D] Canine
Show Answer
Correct Answer: B [Second incisor]
Notes:
Tusks are elongated, continuously growing front teeth (incisors) usually but not always in pairs, that protrude well beyond the mouth of certain mammal species. They are most commonly canines, as with warthogs, pig, and walruses but in the case of elephants, elongated incisors. In most tusked species both the males and the females have tusks although the males’ are larger.
36. Cinnamon is obtained from which part of the plant?
[A] Bark
[B] Stem
[C] Fruits
[D] Roots
Show Answer
Correct Answer: A [Bark]
Notes:
Cinnamon is a spice obtained from the inner bark of several tree species from the genus Cinnamomum. Cinnamon is used mainly as an aromatic condiment and flavoring additive in a wide variety of cuisines. The aroma and flavor of cinnamon derive from its essential oil and principal component, cinnamaldehyde, as well as numerous other constituents, including eugenol.
37. The tissue in man where no cell division occurs after birth is ____:
[A] Nerves
[B] Skeletal
[C] Connective
[D] Germinal
Show Answer
Correct Answer: A [Nerves]
Notes:
Cell division is the process by which cells produce new cells. In animals some tissues must be repaired often such as the lining of gut, white blood cells, skin cells with a short lifespan. Other cells do not divide at all after birth are neurons.
38. A pair of contrasting characters controlling the same trait is called ____:
[A] Allele
[B] Loci
[C] Factors
[D] Lineage
Show Answer
Correct Answer: A [Allele]
Notes:
An allele is one of a pair of genes that appear at a particular location on a particular chromosome and control the same characteristic, such as blood type or colorblindness. Alleles are also called alleleomorphs. If the two alleles are identical, the individual is called a homozygote; when the two alleles are different, the individual is a heterozygote.
39. The sugar present in DNA is ____:
[A] Pentose
[B] Xylulose
[C] Hexose
[D] Heptulose
Show Answer
Correct Answer: A [Pentose]
Notes:
The sugar present in DNA is 2-deoxyribose, which is a pentose sugar. Deoxyribose is one of the three components of nucleotides, the building blocks of DNA. Each nucleotide consists of a phosphate group, a nitrogenous base—adenine (A), thymine (T), cytosine (C), or guanine (G)—and deoxyribose.
40. The liberation of oxygen during photosynthesis is due to ____:
[A] Reduction of CO2
[B] Hydrolysis of carbohydrates
[C] Breakdown of chlorophyll
[D] Photolysis of water
Show Answer
Correct Answer: D [Photolysis of water]
Notes:
In the process of photosynthesis, oxygen is produced from the photolysis of water. The photolysis of water occurs when light is used to renew split water and adenosine triphosphate, also referred to as ATP. The hydrogen remains in the leaf and participates in further reactions. 2H2O(l) = Hydrogen + O2(g)
