1. The echological niche of an organism denotes
a) the habit of an organism
b) its status within a particular community
c) its strucutre and feeding habits
d) the climatic factors of an organism
2. Rubber is obtained from the latex of _________ .
a) stem of Euphorbia spp
b) stem of Carica papaya
c) stem of Hevea brasiliensis
d) fruit of Achras sapota
3. Which of the following does not require external water for fertilization?
a) Mosses
b) Ferns
c) Cycads
d) Liverworts
4. The sporangia of a conifer are located on the
a) scales of the cones
b) tips of the needles
c) base of the needles
d) axils of the branches
5. The transfusion tissue is present in the _________ leaves.
a) Dryopteris
b) Cycas
c) Pinus
d) Cycas and Pinus
6. The number of Cotyledons in Pinus seeds are
a) single
b) two
c) three
d) many
The cotyledons are the “seed leaves” produced by the embryo. Pines are conifers, and are neither monocots
(one cotyledon) nor dicots (two cotyledon). The mature pine seed contains an uncurved embryo with many cotyledons.
7. The conical habit of Pinus is because of
a) efficiency of water movement in plants
b) mutual compition between branches
c) compitition between neighbouring pine trees for sunlight
d) effect of auxin on the growth of stem tip and axillatry branches
8. The largest ovules are found among
a) Monocots
b) Dicots
c) Gymnosperms
d) Angiosperms
9. _________ is an example of a plant which bears seeds but not fruit.
a) Cyas
b) Pea
c) Pinus
d) Selaginella
10. Which one is not true regarding energy flow through ecosystem?
a) Energy inflows balance outflows
b) Even energy transfer is accompanied by dispersion of energy into non available heat
c) The organism near the begining of the food chain gets smaller amount of energy
d) A shorter food chain can support a larger amount of organisms
11. Spot the organisms that are not symbionts.
a) Rhizobium and root of legume plant
b) Nostoc and coalliod root of Cycas
c) Algae and Fungi
d) Vanda and an angiosprem plant
12. The natural cycling of carbon between the organisms and the environment is accomplished
through the process of
a) Photosynthesis and respiration
b) Radiation and immigration
c) Fermentation and oxidation
d) Isolation and dispersal
13. Motile sperm cells are found in all the following except:
a) Cycas
b) Funaria
c) Pteris
d) Rhizopus
14. __________ is an example of symbiotic association of an organism.
a) Alage
b) Fungi
c) Bacteria
d) Root nodule of legume plant
Plant symbiosis : Lichens are peculiar plants formed by the union of a fungus and an alga. They play an
important part in the formation of soils, being the first to colonize rocks.
The relationship between the legume and rhizobia is symbiotic, or mutually beneficial.
The bacteria invade plant root hairs and multiply in the outer root tissue.
15. Gymnosperms are characterised by
a) Naked seeds
b) Seed enclosed in fruits
c) Winged seed
d) Multiple sperms
16. __________ is the edible part of Pinus seed.
a) Pericap
b) Female gametophyte
c) Diploid perisperm
d) Endosprem
17. The tissue in the roots of Vanda that absorbs water from the atmosphere is called
a) Aernchyma
b) Xylem
c) Phloem
d) Velamen
18. Quiescent centre is present in
a) Root apex
b) Shoot apex
c) Vegetative apex
d) Flower apex
19. Tunica and Corpus organization occurs in
a) Root apex
b) Shoot apex
c) Cambium
d) Inter-calary meristems
20. Which of the following tissues form the bulk of storage organ?
a) Parenchyma
b) Collenchyma
c) Sclerenchyma
d) Aerenchyma
21. In a forest ecosystem green plants are
a) the primary producers
b) the secondary consumers
c) the decomposers
d) both secondary consumers and decomposers
22. Various modifications in the form and structure in the leaves of xerophytes are meant
a) to protect from air
b) to protect from excess transpiration
c) to check excess liberation of CO2
d) to help in absorption of O2
23. Etiolation in plants is due to
a) Total darkness
b) Full sunlight
c) Vitamin deficiency
d) Virus disease
Etiolation is a condition caused by the growth of plants in the absence of light. An etiolated plant cannot complete
synthesis of chlorophyll when grown in darkness, so that the leaf is yellowish or whitish, due only to the presence
of yellow carotenoids.In etiolated plants, there are no normal chloroplasts, because in the constant darkness the
typical membrane and protein portions of the organelle cannot be made. So Etiolation in platns is due to the absence
of a growth-inhibiting secretion formed by the chloroplasts In the light.
24. Sunken stomata are found in
a) Epiphytes
b) Hydrophytes
c) Mesophytes
d) Xerophytes
25. Opuntia is a cactus which is a
a) Ephemeral animal
b) Succulent
c) Non-succulent
d) Cladode
Opuntia is a succulent plant. it is a genus of cactus that contains more than 360 species of plants.
The most commonly known plant in the optunia genus is the nopal opuntia, or prickly pear cactus.
26.The ecological factors of soil and its environment and their interactions with the growth of
plants comes under the following factors:
a) Biotic factors
b) Abiotic factors
c) Edaphic factors
d) Climatic factors
27. _________ is an example of a free floating hydrophyte.
a) Eichhornia
b) Vallisneria
c) Nymphaea
d) Typha
28. An ecosystem can not continue functioning without a constant input of energy because
a) it is lost at each trophic level
b) it flows in an ecosystem that lacks organisms that store energy
c) an ecosystem includes decomposers in its community
d) of climate change and fast ubanization
29. The largest amount of water that is availalbe for the plants from soil is
a) Gravtiational water
b) Capilary water
c) Hygroscopic water
d) Soil water vapour
30. Polytene chromosome are found in
a) salivary glands of men
b) salivary glands of animals
c) salivary glands of women
d) salivary glands of Drosophila
31. What are the chromosomes with more than two chromatids called?
a) Lampbrush chromosomes
b) Polytene chromosomes
c) Acrocentric chromosomes
d) Allosomes
32. Genes for antibiotic resitance are located in
a) Chromosome DNA
b) Plasmid
c) RNA
d) Polymerase
33. A codon refers to
a) a unit of recombination
b) a unit that undergo mutation
c) a set of bases in DNA which code one amino acid
d) any functional unit of DNA
34. __________ enzyme that helps in DNA replication.
a) Nucleotidase
b) Arginase
c) DNA polymerase
d) Protease
35. __________ helps in DNA replication.
a) Amylase
b) Ligase
c) Luciferase
d) Hexokinase
36. A colour blind man marries the daughter of a colour blind person. Then in their progeny
a) none of their daughters are colour blind
b) all their daughters are colour blind
c) all their sons are colour blind
d) half their sons are colour blind
37. There is no masking of expression of genes in Neurospora because
a) it has a short generation span
b) it is haploid
c) it requires minimum number of nutrients
d) it is diploid
38. Tyloses are balloon-like ingrowths seen in vessels of
a) primary xylem developing from adjoining parenchyma
b) secondary xylem developing from adjoining parenchyma
c) primary xylem developing from adjoining fibres
d) secondary xylem developing from adjoining fibres
39. Which of the following statements is wrong?
a) Primary growth causes increase in height whereas secondary growth accounts for
increase in diameter
b) The bark is a tissue outside cortex
c) The cambium is composed of two kinds of initials
d) In woody plants cambium functions for few years
40. ______________ is the characteristic of a vascular bundle of monocot stem.
a) Open and surrounded by a sclerenchymatous bundle sheath
b) Closed and not surrounded by a bundle sheath
c) Closed and surrounded by a bundle sheath
d) Open and not surrounded by a bundle sheath
41. Parenchymatous tissue is characterized by
a) uniform thickening
b) thickening of the corners
c) lignified walls
d) intercellular spaces
42. Cambium is considered a lateral meristem because
a) it increases the height and diameter of a stem
b) it gives rise to lateral branches
c) it increases the girth of a plant
d) it increases the length of a plant
43. Primary growth is caused by (or) the length of a plant axis increases by
a) Apical meristem
b) Lateral meristem
c) Dermatogen
d. Plerome
44. A meristem may be defined as the group of cells which
a) do not divide
b) conserve food and fight against bio-stresses
c) divide continuously to give rise to new cells
d) elongate and add to the group of cells
45. Knowing that albinism is determined by a recessive gene in man, presence of albinism in the
children brone to a normal couple proves that
a) both the mother and father are heterozygous for albinism
b) the father is homozygous normal but the mother is heterozygous
c) the father is homozygous for albinism but mother is heterozygous
d) father and mother are homozygous normal
A very good question from Genetics branch that i would like to discuss here. Please put your answer
in comment section if i am wrong in my explanation. I have not studied Biology as a subject in my
course during graduation, but i always like to read this subject in spare time as this subject play an
important role in our daily life.
Firstly the meaning of Albinism:
Albinism occurs when one of several genetic defects makes the body unable to produce or distribute
melanin, a natural substance that gives color to your hair, skin, and iris of the eye. The ability to produce
melanin is anchored in our genes. If the genes for melanin production are missing or altered little or no
color is produced. Albinism results from inheritance of recessive gene alleles and is known to affect all
vertebrates, including humans. It is a genetic condition which means that it can be passed from parents
to their children. People with Albinism have a white skin, blonde or reddish hair and brown, grey or blue
eyes.People with albinism have little or no pigment in their eyes, skin, or hair. Humans, animals, and
even plants can have albinism.
In mammals, the female is the homozygous sex with two X chromosomes [XX], while the male is
heterozygous, with one X and one Y chromosome [XY]. Genes on the X or Y chromosome are called
sex linked genes.
Here in the question, two things are clearly given i.e. presence of albinism in child and normal couple.
A normal couple means that a male with out Albino gene married to a female having Albino gene which
act as a sailent carrier of Albino gene for next generation (because child shows the presence of Albino
gene).
I have used following notations to explain it more
Xa : X chromosome carries allele ‘a’ for albinism
Ya : Y chromosome carries allele ‘a’ for albinism
X : X chromosome with out allele ‘a’ for albinism
Y : Y chromosome with out allele ‘a’ for albinism
Now, Homozygous Albino vs Heterozygous Albino:
A person is said to be homozygous Albino if it received the Albino gene from both its mother and father.
[ XaYa ] : Male Homozygous Albino [ XaXa ] : Female Homozygous Albino
[ XX] : Normal Female Homozygous with out Albino gene
A heterozygous Albino will contain one and only one Albino gene from either the father or mother.
[ XaY] : Male Heterozygous Albino [ Albino gene received from mother ]
[ XYa ] : Male Heterozygous Albino [ Albino gene received from father ]
[ XXa ] : Normal Female Heterozygous Albino [ Albino gene received from mother and act
as a sailent carrier for next generation ]
[ XY] : Normal Male Heterozygous with out Albino gene
As per question, for a normal couple and the presence of albinism in child:
Male [ Xa ] [ X ] ¬Female
¯ [ X ] [XXa] [XX]
[ Y ] [XaY] [XY]
So, the correct answer should be modified as :
the father is heterozygous normal but the mother is heterozygous.
All humans are heterozygous for recessive alleles that, if present homozygously,
would be lethal. This is sometimes referred to as the “genetic load.”
46. In an E.coli according to the operon theory an operator gene combines with
a) inducer gene to ‘switch on’
b) regulator gene to ‘switch off’
c) regulator protien to ‘switch off’ structural gene transcription
d) regulator protien to ‘switch on’ structural gene transcription
47. Which of the following is haploid in gymnosprems?
a) Pollen grains, megaspore, root
b) Pollen grains, megaspore, nucellus
c) Megaspore mother cell, root, leaf
d) Endosprem, pollen grains, megaspore
48. Cycas has two cotyledons but is not included in angiosperms because of
a) stems like monocot
b) large ovule
c) naked ovule
d) compound leaves
49. Chromosome theory of heredity was formulated for the first time on the basis os the following
observations:
a) Chromosomes exhibit segregation and independent assortment during meiosis
b) There are a fixed number of chromosomes in each cell of an organism
c) Chromosomes are the main structures in nucleus
d) Determination os sex is through sex chromosomes
50. Self-replicating cytoplasmic particles are capable of transmitting traits in inheritance to
a) Mutagenes
b) Regulator genes
c) Plasma genes
d) Operator genes
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