26035.Which of the following most appropriately describes haemophilia?
Dominant gene disorder
Recessive gene disorder
X-linked recessive gene disorder
Chromosomal disorder
Explanation:
Heamophilia is X-linked recessive disorder which causes defect in the clotting factor formation, thus a simple cut can bleed continuously leading to even death. Thus, it is also known as ‘Bleeders’ disease or ‘Royal Disease’ as Queen Victoria is a carrier for this disease.
Heamophilia is X-linked recessive disorder which causes defect in the clotting factor formation, thus a simple cut can bleed continuously leading to even death. Thus, it is also known as ‘Bleeders’ disease or ‘Royal Disease’ as Queen Victoria is a carrier for this disease.
26036.Select the correct statement:
The leaves of gymnosperms are not well adapted to extremes of climate
Gymnosperms are both homosporous and heterosporous
Salvinia, Ginkgo, and Pinus all are gymnosperms
Sequoia is one of the tallest trees
Explanation:
Sequoia is tallest tree which is a Gymnosperm. It can be 130-140 metres tall.
Sequoia is tallest tree which is a Gymnosperm. It can be 130-140 metres tall.
26037.Which of the following is required as inducer(s) for the expression of Lac operon?
lactose and galactose
glucose
galactose
lactose
Explanation:
Lactose binds to repressor protein and prevents it from binding to operator gene.
Lactose binds to repressor protein and prevents it from binding to operator gene.
26038.A tall true breeding garden pea plant is crossed with a dwarf true breeding garden pea plant. When the F1 plants were selfed the resulting genotypes were in the ratio of
3 : 1 :: Dwarf : Tall
1 : 2 : 1 :: Tall homozygous: Tall heterozygous : Dwarf
1 : 2 : 1 :: Tall heterozygous: Tall homozygous : Dwarf
3 : 1 :: Tall : Dwarf
Explanation:
26040.Which of the following is not a characteristic feature during mitosis in somatic cells?
Synapsis
Spindle fibres
Disappearance of nucleolus
Chromosome movement
Explanation:
Synapsis is the process of attachment of the homologous chromosomes during zygotene stgage of prophase I of meiosis.
Synapsis is the process of attachment of the homologous chromosomes during zygotene stgage of prophase I of meiosis.
26041.Which of the following statements is not true for cancer cells in relation to mutations?
Mutations inhibit production of telomerase.
Mutations in proto-oncogenes accelerate the cell cycle.
Mutations destroy telomerase inhibitor.
Mutations inactivate the cell control.
Explanation:
In cancer cells telomerase is expressed and its production is not inhibited due to mutations leadings to cancer formation.
In cancer cells telomerase is expressed and its production is not inhibited due to mutations leadings to cancer formation.
26042.One of the major components of cell wall of most fungi is:
Hemicellulose
Chitin
Peptidoglycan
Cellulose
Explanation:
Peptidoglycan - Bacterial cell wall. Cellulose and Hemicellulose - plant cell wall.
Peptidoglycan - Bacterial cell wall. Cellulose and Hemicellulose - plant cell wall.
26043.Cotyledon of maize grain is called:
scutellum
plumule
coleorhiza
coleoptile
Explanation:
Major part of maize grain is occupied by endosperm whereas a single large cotyledon is present that is called Scutellum.
Major part of maize grain is occupied by endosperm whereas a single large cotyledon is present that is called Scutellum.
26044.Which of the following would appear as the pioneer organisms on bare rocks?
Green algae
Lichens
Liverworts
Mosses
Explanation:
The first biospecies that appears for the first time on bare rock is lichens which is followed by Bryophytes.
The first biospecies that appears for the first time on bare rock is lichens which is followed by Bryophytes.
26045.Changes in GnRH pulse frequency in females is controlled by circulating levels of:
progesterone and inhibin
estrogen and progesterone
estrogen and inhibin
progesterone only
Explanation:
GnRH pulse frequency in females is controlled by circulating levels of oestrogen & progesterone.
GnRH pulse frequency in females is controlled by circulating levels of oestrogen & progesterone.
26046.Antivenom injection contains preformed antibodies while polio drops that are administered into the body contain:
Attenuated pathogens
Activated pathogens
Harvested antibodies
Gamma globulin
Explanation:
Polio drops - Oral Polio Vaccine also known as Sabin Vaccine is prepared with live attenuated pathogens.
Polio drops - Oral Polio Vaccine also known as Sabin Vaccine is prepared with live attenuated pathogens.
26047.Photosensitive compound in human eye is made up of:
Transducin and Retinene
Guanosine and Retinol
Opsin and Retinal
Opsin and Retinol
Explanation:
Photosensitive compounds in human eye i.e. in Rods & Cones is Opsin & Retinal.
Photosensitive compounds in human eye i.e. in Rods & Cones is Opsin & Retinal.
26048.Specialised epidermal cells surrounding the guard cells are called:
Lenticels
Complementary cells
Subsidiary cells
Bulliform cells
Explanation:
Guard cells of stomata are surrounded by subsidiary cells which locks chloroplast and works in co-ordination of guard cells to maintain the turgidity of the cell which regulates the opening and closing of stomata.
Guard cells of stomata are surrounded by subsidiary cells which locks chloroplast and works in co-ordination of guard cells to maintain the turgidity of the cell which regulates the opening and closing of stomata.
26049.Which of the following features is not present in the Phylum – Arthropoda?
Jointed appendages
Chitinous exoskeleton
Metameric segmentation
Parapodia
Explanation:
Arthropods have chitinous exoskeleton, show metameric segmentation and jointed appendages.
Parapodia is a characteristics of annelida helping them in locomotion.
Arthropods have chitinous exoskeleton, show metameric segmentation and jointed appendages.
Parapodia is a characteristics of annelida helping them in locomotion.
26050.Reduction in pH of blood will:
release bicarbonate ions by the liver.
reduce the rate of heart beat.
reduce the blood supply to the brain.
decrease the affinity of hemoglobin with oxygen.
26051.Which of the following characteristic features always holds true for the corresponding group of animals ?
3 – chambered heart with one incompletely divided ventricle - Reptilia
Cartilaginous endoskeleton - Chondrichthyes
Viviparous - Mammalia
Possess a mouth with an upper and a lower jaw - Chordata
Explanation:
Chondrichthyes has endoskeleton made up of cartilage.
All Mammals are Viviparous except platypus which is Oviparous.
All Chordates posses a mouth with an upper and a lower jaw except agnatha which are without jaws.
All reptiles have 3 - chambered heart except crocodile and tortoise in which heart is four chambered.
Chondrichthyes has endoskeleton made up of cartilage.
All Mammals are Viviparous except platypus which is Oviparous.
All Chordates posses a mouth with an upper and a lower jaw except agnatha which are without jaws.
All reptiles have 3 - chambered heart except crocodile and tortoise in which heart is four chambered.
26052.Match the terms in Column I with their description in Column II and choose the correct option:
Code:
(a) (b) (c) (d)
| Column I | Column II |
|---|---|
| (a) Dominance | (i) Many genes govern a single character |
| (b) Codominance | (ii) In a heterozygous organism only one allele expresses itself |
| (c) Pleiotropy | (iii) In a heterozygous organism both alleles express themselves fully |
| (d) Polygenic inheritance | (iv) A single gene influences many characters |
Code:
(a) (b) (c) (d)
(iv) (iii) (i) (ii)
(ii) (i) (iv) (iii)
(ii) (iii) (iv) (i)
(iv) (i) (ii) (iii)
Explanation:
Dominance - In a heterozygous organism only one allele expresses itself.
Codominance - In a heterozygous organism both alleles experess themselves equally.
Pleiotropy - A single gene influences many characters.
Polygenic Inheritance - Many genes govern a single character.
Dominance - In a heterozygous organism only one allele expresses itself.
Codominance - In a heterozygous organism both alleles experess themselves equally.
Pleiotropy - A single gene influences many characters.
Polygenic Inheritance - Many genes govern a single character.
26053.A typical fat molecule is made up of:
Three glycerol and three fatty add molecules
Three glycerol molecules and one fatty acid molecule.
One glycerol and three fatty acid molecules
One glycerol and one fatty acid molecule
26054.Proximal end of the filament of stamens attached to the:
Thalamus or petal
Anther
Connective
Placenta
Explanation:
Proximal end of the filament of stamen is attached to the Thalamus or petal and distal end is attached to anther.
Proximal end of the filament of stamen is attached to the Thalamus or petal and distal end is attached to anther.