Test 10 (Class 12)- Type Bio SCAN (Old NCERT)Contact Number: 9667591930 / 8527521718Test 10 (Class 12)- Type Bio SCAN (Old NCERT)Contact Number: 9667591930 / 8527521718A typical angiospermic embryo sac is:
| 1. | 8 - nucleate, 8 - celled |
| 2. | 7 - nucleate, 8 - celled |
| 3. | 8 - nucleate, 7 - celled |
| 4. | 7 - nucleate, 6 - celled |
Capacitation refers to change in the
1. Sperm before fertilisation
2. Ovum before fertilisation
3. Ovum after fertilisation
4. Sperm after fertilisation
Vegetative propagule in Agave is as:
1. Rhizome
2. Bulbil
3. Offset
4. Eye
Which of the following cells during gametogenesis is normally diploid?
| 1. | Primary polar body |
| 2. | Spermatid |
| 3. | Spermatogonia |
| 4. | Secondary polar body |
Apomictic embryos in Citrus arise from:
1. synergids
2. maternal sporophytic tissue in ovule
3. antipodal cells
4. diploid egg
Which one of the following may require pollinators, but is genetically similar to autogamy?
1. Xenogamy
2. Apogamy
3. Cleistogamy
4. Geitonogamy
Which of the following secretes the hormone, relaxin, during the later phase of pregnancy?
1. Foetus
2. Uterus
3. Graafian follicle
4. Corpus luteum
Vegetative propagation in Mint occurs by
1. Sucker
2. Runner
3. Offset
4. Rhizome
Which one of the following is surrounded by a callose wall?
1. Microspore mother cell
2. Male gamete
3. Egg
4. Pollen grain
The first movements of the fetus and the appearance of hair on the head are usually observed during:
| 1. | 2nd month of pregnancy |
| 2. | 3rd month of pregnancy |
| 3. | 5th month of pregnancy |
| 4. | 7th month of pregnancy |
Persistent nucellus in the seed is known as:
1. Tegmen
2. Chalaza
3. Perisperm
4. Hilum
No new follicles develop in the luteal phase of the menstrual cycle because :
1. Follicles do not remain in the ovary after
2. FSH levels are high in the luteal phase
3. LH levels are high in the luteal phase
4. Both FSH and LH levels are low in the luteal phase
Endosperm is consumed by developing embryo in the seed of
1. Coconut
2. Pea
3. Maize
4. Castor
Which of the following plants is monoecious?
1. Marchantia polymorpha
2. Cycas circinalis
3. Carica papaya
4. Chara
Function of filiform apparatus is to:
| 1. | Recognize the suitable pollen at the stigma |
| 2. | Stimulate division of generative cell |
| 3. | Producer nectar |
| 4. | Guide the entry of the pollen tube |
What happens when a sperm enters the cytoplasm of the secondary oocyte?
1. Release of first polar body
2. Completion of meiosis II
3. Degeneration of polar bodies
4. Dissolution of zona pellucida
Vasa efferentia are the ductules leading from
1. testicular lobules to rete testis
2. rete testis to vas deferens
3. vas deferens to epididymis
4. epididymis to urethra
Which part of the ovary in mammals acts as an endocrine gland after ovulation?
| 1. | Graafian follicle |
| 2. | Stroma |
| 3. | Germinal epithelium |
| 4. | Vitelline membrane |
A mechanism that can cause a gene to move from one linkage group to another is :
1. Translocation
2. Inversion
3. Crossing over
4. Duplication
Which of the following contraceptive methods do involve a role of hormone?
1. Pills, Emergency contraceptives, barrier methods
2. Lactational amenorrhea, Pills, Emergency contraceptives
3. Barrier method, Lactational amenorrhea, pills
4. CuT, Pills, Emergency contraceptives
Identify a sexually transmitted disease amongst the following that is completely curable.
1. HIV
2. Hepatitis B
3. Genital herpes
4. Trichomoniasis
Female heterogamety is seen in:
| 1. | Drosophila melanogaster |
| 2. | Many birds |
| 3. | Honey bee |
| 4. | Grasshopper |
Which of the following most appropriately describes haemophilia?
| 1. | Dominant gene disorder |
| 2. | Recessive gene disorder |
| 3. | X-linked recessive gene disorder |
| 4. | Chromosomal disorder |
Mating between a male with blood group A and a female with blood group B results in the progeny with blood group AB can be explained by:
1. Complete dominance
2. Incomplete dominance
3. Co-dominance
4. Epistasis
1. Twelve weeks
2. Eighteen weeks
3. Six weeks
4. Eight weeks
Match the following RNA polymerases with their transcribed products:
|
Column-I |
Column-II |
||
|
(a) |
RNA polymerase I |
(i) |
tRNA |
|
(b) |
RNA polymerase II |
(ii) |
rRNA |
|
(c) |
RNA polymerase III |
(iii) |
hnRNA |
Select the correct option from the following:
1. (a)-(i), (b)-(iii), (c)-(ii)
2. (a)-(i), (b)-(ii), (c)-(iii)
3. (a)-(ii), (b)-(iii), (c)-(i)
4. (a)-(iii), (b)-(ii), (c)-(i)
The bacterial DNA is mainly composed of:
1. Ori sequences.
2. Structural gene sequences.
3. Intergenic regions.
4. Introns.
Multivalent chromosome is formed by:
1. Inversion
2. Deletion
3. Reciprocal translocation
4. Point mutation
Which of the following statements is not true of two genes that show 50% recombination frequency?
| 1. | The genes are tightly linked. |
| 2. | The genes show independent assortment. |
| 3. | If the genes are present on the same chromosome, they undergo more than one crossing-over in every meiosis. |
| 4. | The genes may be on different chromosomes. |
A normal woman, whose father was colour-blind is married to a normal man. The sons would be:
1. 50% colour-blind
2. All normal
3. All colour-blind
4. 75 % colour-blind
If one strand of DNA has the nitrogenous base sequence as ATCTG, what would be the complementary RNA strand sequence?
1. TTAGU
2. UAGAC
3. AACTG
4. ATCGU
Which one of the following is the start codon?
1. UAG
2. AUG
3. UGA
4. UAA
Cri-du-chat syndrome in humans is caused by the:
| 1. | fertilization of an XX egg by a normal y-bearing sperm |
| 2. | loss of half of the short arm of chromosome 5 |
| 3. | loss of half of the long arm of chromosome 5 |
| 4. | trisomy of 21st chromosome |
When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is:
1. Pentaploidy
2. Diploidy
3. Triploidy
4. Tetraploidy
The similarity between DNA and RNA is that both:
1. are polymers of nucleotides
2. have a similar pyrimidine
3. have similar sugars
4. genetic material
Chromosomal theory of inheritance was proposed by:
| 1. | Sutton and Boveri |
| 2. | Bateson and Punnet |
| 3. | T. H. Morgan |
| 4. | Watson and Crick |
Purines found both in DNA and RNA are:
| 1. | Cytosine and thymine |
| 2. | Adenine and thymine |
| 3. | Adenine and guanine |
| 4. | Guanine and cytosine |
The functions of the telomeres include:
| I: | They prevent chromosomes from fusing with each other. |
| II: | They prevent chromosomes from shrinking due to DNA loss during replication. |
| III: | They allow chromosomes to segregate properly during cell division. |
| 1. | I and II only |
| 2. | I and III only |
| 3. | II and III only |
| 4. | I, II, and III |
The lac Operon consists of:
| 1. | One regulatory gene and three structural genes |
| 2. | Two regulatory genes and two structural genes |
| 3. | Three regulatory genes and three structure genes |
| 4. | Four regulatory genes only |
Removal of RNA polymerase III from nucleoplasm will affect the synthesis of:
1. tRNA
2. hnRNA
3. mRNA
4. rRNA
In eukaryotic cell transcription, RNA splicing and RNA capping take place inside the:
1. Nucleus
2. Dictyosomes
3. ER
4. Ribosomes
Flowering plants (angiosperms) first appeared during :
1. Paleozoic era
2. Carboniferous period
3. Cretaceous period
4. Cenozoic era
Embryological support for evolution was disapproved by:
1. Alfred Wallace
2. Charles Darwin
3. Oparin
4. Karl Ernst von Baer
Which of the following refer to correct example(s) of organisms which have evolved due to changes in environment brought about by anthropogenic action?
(a) Darwin's Finches of Galapagos islands
(b) Herbicide resistant weeds
(c) Drug resistant eukaryotes
(d) Man-created breeds of domesticated animals like dogs
(1) (a) and (c)
(2) (b), (c) and (d)
(3) only (d)
(4) only (a)
The similarity of bone structure in the forelimbs of many vertebrates is an example of:
1. Convergent evolution
2. Analogy
3. Homology
4. Adaptive radiation
Which statement is correct for bacterial transduction:
| 1. | Transfer of some genes from one bacteria to another bacteria through virus |
| 2. | Transfer of some genes from one bacteria to another bacteria by conjugation |
| 3. | Bacteria obtained their DNA directly |
| 4. | Bacteria obtained DNA from other external sources |
Identify the incorrectly matched pair:
|
1. |
Ichthyosaurs |
Evolved into fish like reptiles |
|
2. |
Coelacanths |
Evolved into first amphibians |
|
3. |
Home erectus |
Had a cranial capacity of around 900 cc |
|
4. |
Home habilis |
Probably ate meat |
Which one of the following is not a living fossil?
1. King crab
2. Sphenodon
3. Archaeopteryx
4. Peripatus
Among the following sets of examples for divergent evolution, select the incorrect option:
1. Brain of bat, man and cheetah
2. Heart of bat, man and cheetah
3. Forelimbs of man, bat and cheetah
4. Eye of octopus, bat and man