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Worksheetsunit 18 & 19
Total questions: 25
Worksheet time: 16mins
Biogenetic law states that ______________
a. Ontogeny and phylogeny go together
b. Ontogeny recapitulates phylogeny
c. Phylogeny recapitulates ontogeny
d. There is no relationship between
phylogeny and ontogeny
The ‘use and disuse theory’ was proposed
by ______________.
a. Charles Darwin
b. Ernst Haeckel
c. Jean Baptiste Lamarck
d. Gregor Mendel
Paleontologists deal with
a. Embryological evidences
b. Fossil evidences
c. Vestigial organ evidences
d. All the above
The best way of direct dating fossils of
recent origin is by
a. Radio-carbon method
b. Uranium lead method
c. Potassium-argon method
d. Both (a) and (c)
The term Ethnobotany was coined by
a. Khorana
b. J.W. Harsbberger
c. Ronald Ross
d. Hugo de Vries
The characters developed by the animals
during their life time, in response to
the environmental changes are called
(a) .
The forelimbs of bat and human are
examples of (a) organs.
Birds have evolved from reptiles.
True
False
Atavism
caudal vertebrae and vermiform appendix
a forelimb of a cat and a bat’s wing
rudimentary tail and thick hair on the body
a wing of a bat and a wing of an insect
Wood park
radiocarbon dating
Thiruvakkarai
a forelimb of a cat and a bat’s wing
rudimentary tail and thick hair on the body
According to Mendel alleles have the
following character
a) Pair of genes
b) Responsible for character
c) Production of gametes
d) Recessive factors
9 : 3 : 3 : 1 ratio is due to
a) Segregation
b) Crossing over
c) Independent assortment
d) Recessiveness
The region of the chromosome where
the spindle fibres get attached during cell
division
a) Chromomere
b) Centrosome
c) Centromere
d) Chromonema
The centromere is found at the centre of the
________________ chromosome.
a) Telocentric
b) Metacentric
c) Sub-metacentric
d) Acrocentric
The _____________ units form the
backbone of the DNA.
a) 5 carbon sugar
b) Phosphate
c) Nitrogenous bases
d) Sugar phosphate
Okasaki fragments are joined together by
___________________.
a) Helicase
b) DNA polymerase
c) RNA primer
d) DNA ligase
The number of chromosomes found in
human beings are __________________.
a) 22 pairs of autosomes and 1 pair of
allosomes.
b) 22 autosomes and 1 allosome
c) 46 autosomes
d) 46 pairs autosomes and 1 pair of
allosomes.
The loss of one or more chromosome in a ploidy
is called ___________.
a) Tetraploidy
b) Aneuploidy
c) Euploidy
d) polyploidy
Physical expression of a gene is called
(a)
A typical Mendelian dihybrid ratio of F2
generation is 3:1.
False
True
Each gamete has only one allele of a gene.
True
False
Down’s syndrome is the genetic condition
with 45 chromosomes.
True
False
Autosomes
Trisomy 21
9:3:3:1
22 pair of chromosome
2n
23rd pair of chromosome
Allosome
Trisomy 21
9:3:3:1
2n
23rd pair of chromosome
Dihybrid ratio
23rd pair of chromosome
22 pair of chromosome
Trisomy 21
9:3:3:1
