Bihar Board 12th Biology Important Questions Objective Type Part 6 are the best resource for students which helps in revision.
Bihar Board 12th Biology Objective Important Questions Part 6
Question 1.
The number of Linkage groups in a cell having 2n = 20 are
(a) 5
(b) 10
(c) 15
(d) 20
Answer:
(b) 10
Question 2.
Anemophily can best be seen in:
(a) Maize
(b) Vallisneria
(c) Salvia
(d) Yueca
Answer:
(a) Maize
Question 3.
Wucheria wankrufu causes filaria in human being is a:
(a) Protozoa
(b) Bacteria
(c) Virus
(d) Helminth
Answer:
(d) Helminth
Question 4.
Widal test in done to confirm:
(a) Malaria
(b) Typhoid
(c) AIDS
(d) Cancer
Answer:
(b) Typhoid
Question 5.
Which of the following enzyme is used to cleave the DNA for recombinant DNA technology:
(a) Restriction endonuclease
(b) Topoisomerase (I)
(c) Topoisomerase (II)
(d) Ligase
Answer:
(a) Restriction endonuclease
Question 6.
Termination of Transcription is brought about by:
(a) Co-protein
(b) Sigma-factor
(c) Rho-protein
(d) Omega factor
Answer:
(c) Rho-protein
Question 7.
Gestation period in humans is:
(a) 10 weeks
(b) 25 weeks
(c) 28 weeks
(d) 36 weeks
Answer:
(d) 36 weeks
Question 8.
Lysozyme is present in:
(a) Saliya
(b) Gastric enzymes
(c) Tears
(d) Pancreatic juice
Answer:
(c) Tears
Question 9.
An antibody molecule has:
(a) One polypeptide chain
(b) Two polypeptide chain
(c) Three polypeptide chain
(d) Four polypeptide chain
Answer:
(d) Four polypeptide chain
Question 10.
In DNA, if adenine = a, guanine = b, cytosine = c and thymine = d. Which of the following represent correct equation
(a) a + b = b + c
(b) a + b = c + d
(c) a + c = b + d
(d) a + d = b + c
Answer:
(b) a + b = c + d
Question 11.
Which of the following sites RNA polymerase attaches to for transcription
(a) Promoter
(b) Regulator
(c) Structural
(d) None
Answer:
(a) Promoter
Question 12.
The nutritive cells found in seminiferous tubules are:
(a) Sertoli cells
(b) Leydig cells
(c) Spermatogonial cells
(d) Epithelial cells
Answer:
(a) Sertoli cells
Question 13.
The Single Shield shaped Cotyledon in monocots is called:
(a) Seutellum
(b) Epiblast
(c) Tigellum
(d) None of the above
Answer:
(a) Seutellum
Question 14.
The term coupling & repulsion are two sides of the same coin of:
(a) Linkage
(b) Synapsis
(c) Disjunction
(d) Non-disjunction
Answer:
(b) Synapsis
Question 15.
Secondary producers are:
(a) Herbivores
(b) Producers
(c) Carnivores
(d) None
Answer:
(a) Herbivores
Question 16.
The genotypic ratio in monohybrid cross is:
(a) 3 : 1
(b) 9 : 3 : 3 : 1
(c) 1 : 2 : 1
(d) None
Answer:
(c) 1 : 2 : 1
Question 17.
Exposure of X-rays increases the frequency of:
(a) Crossing over
(b) Non ctoss-over
(c) Linkage
(d) Independent assortment
Answer:
(a) Crossing over
Question 18.
The colour of human blood is red due to presence of:
(a) Haemozoin
(b) Haemoglobin
(c) Iron
(d) Red pigment
Answer:
(b) Haemoglobin
Question 19.
The science of raising, feeding, management & breeding of animals is called:
(a) Veterinary Science
(b) Dairy Science
(c) Cattle farming
(d) Animal husbandry
Answer:
(d) Animal husbandry
Question 20.
The fusion of male gamete with secondary nucleus is known as:
(a) Syngamy
(b) Xenogamy
(c) Triple fusion
(d) None
Answer:
(c) Triple fusion
Question 21.
Which one is a sex-linked disease?
(a) Sickle-cell anaemia
(b) Phenylketonuria
(c) Haemophilia
(d) Albinism
Answer:
(c) Haemophilia
Question 22.
When the anthers mature before the stigma, it is known as:
(a) Dicliny
(b) Heterostyly
(c) Protandry
(d) Protogyny
Answer:
(c) Protandry
Question 23.
Copper-T prevents.
(a) Ovulation
(b) Pollination
(c) Fertilisation
(d) Implantation
Answer:
(a) Ovulation
Question 24.
An exception of Mendel’s is law is:
(a) Dominance
(b) Purity of gametes
(c) Linkage
(d) Independent assortment
Answer:
(c) Linkage
Question 25.
What is the percentage of photosynthetically active radiation (PAR) in the incident solar radiation?
(a) 100%
(b) 50%
(c) 1.5%
(d) 2.1%
Answer:
(b) 50%
Question 26.
“Syndrome” means:
(a) Diseased condition
(b) Virulency of pathogens
(c) Malignancy
(d) A group of symptoms
Answer:
(d) A group of symptoms
Question 27.
Vector insects are those which:
(a) Spread disease
(b) Destroy crops
(c) Cause disease
(d) Destroy humans
Answer:
(a) Spread disease
Question 28.
In F2 generation, phenotypic & genotypic ratios are similar in:
(a) Monohybrid cross
(b) Dihybrid cross
(c) Incomplete dominance
(d) Complementary genes
Answer:
(c) Incomplete dominance
Question 29.
In DNA, A equals:
(a) C
(b) G
(c) T
(d) None
Answer:
(c) T
Question 30.
Crystals of Bt toxins produced by some bacteria do not kill the bacteria themselves because:
(a) Bacteria are resistant to the toxin
(b) Toxin in not matured
(c) Toxins are inactive
(d) Bacteria incloses toxins in a special sac.
Answer:
(c) Toxins are inactive
Question 31.
The chromosomal constitution of klinefelter’s syndrome is:
(a) 2A + XY
(b) 2A + XO
(c) 2A + XX
(d) 2A + XXY
Answer:
(d) 2A + XXY
Question 32.
The fusion of male gamete with secondary nucleus Is known as
(a) Syngamy
(b) Xenogamy
(c) Triple fusion
(d) None
Answer:
(c) Triple fusion
Question 33.
Select the statement which explains best parasitism:
(a) One organism is benefited
(b) Both the organism are benefited
(c) One organism are benefited other is not affected
(d) One organism is benefited, other is affected
Answer:
(d) One organism is benefited, other is affected
Question 34.
Homo sapiens arose in:
(a) Africa
(b) Asia
(c) Europe
(d) Australia
Answer:
(b) Asia
Question 35.
Amoebiasis is caused due to:
(a) Entamoeba histolitica
(b) Plasmodium
(c) Streptococcus
(d) Wuchareia bancrofti
Answer:
(a) Entamoeba histolitica
Question 36.
Perisperm is the remained portion of:
(a) Nucleus
(b) Embryo
(c) Endosperm
(d) Integument
Answer:
(a) Nucleus
Question 37.
The process of double fertilization was discovered by
(a) Strasburger
(b) Robert Koch
(c) Nawaschin
(d) Huxley
Answer:
(c) Nawaschin
Question 38.
Which one of the following has largest population in a food-chain:
(a) Producer
(b) Primary Consumer
(c) Secondary consumer
(d) Decomposer
Answer:
(a) Producer
Question 39.
Malaria is caused due to:
(a) Protozoa
(b) Algae
(c) Fungi
(d) Malnutrition
Answer:
(a) Protozoa
Question 40.
According to Mendelism which characters are dominant:
(a) Tall plant, wrinked seed (B)
(b) Tall plant, round seed
(c) Dwarf plant, wrinkled seed
(d) Dwarf plant, round seed
Answer:
(b) Tall plant, round seed
Question 41.
The genotypic ratio in monohybrid cross is:
(a) 3 : 1
(b) 9 : 3 : 3 : 1
(c) 1 : 2 : 1
(d) None
Answer:
(c) 1 : 2 : 1
Question 42.
The term humulin is used for:
(a) A firm of chitin
(b) A digestive enzyme
(c) A powerful antibiotics
(d) human insulin
Answer:
(d) human insulin
Question 43.
Balance between CO2 & O2 is maintained due to:
(a) Photorespiration
(b) Respiration
(c) Photosynthesis
(d) Leaf anatomy
Answer:
(c) Photosynthesis
Question 44.
An exception of Mendel’s law is:
(a) Dominance
(b) Purity of gamete
(c) Linkage
(d) Independent assortment
Answer:
(c) Linkage
Question 45.
Lampbrush chromosomes found in the oocytes of amphibians are seen in:
(a) Leptotene
(b) Diplotene
(c) Pachytene
(d) None
Answer:
(b) Diplotene
Question 46.
The main difference between gram positive (+) and gram negative (-) bacteria lies in:
(a) Pili
(b) Cell Wall
(c) Flagella
(d) Plasmids
Answer:
(b) Cell Wall
Question 47.
In pond/forest ecosystem pyramid of energy is:
(a) Always upright
(b) always inverted
(c) Both upright & inverted
(d) Shaped
Answer:
(a) Always upright
Question 48.
What is the main contribution of Neo-Darwinians to theory of Darwinism?
(a) Photorespiration
(b) Respiration
(c) Photosynthesis
(d) Leaf anatomy
Answer:
(d) Leaf anatomy
Question 49.
Ovulation occurs under the influence of:
(a) LH
(b) FSH
(c) Estrogen
(d) Progesterone
Answer:
(a) LH
Question 50.
Number of sperms formed from one primary spermatocyte is:
(a) 8
(b) 4
(c) 3
(d) 1
Answer:
(b) 4