Biology Test 33

Result

Biology Test 33

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
4 / -1

Darwin's finches are an excellent example of

A
adaptive radiation

B
seasonal migration

C
brood parasitism

D
connecting links

Solution

Adaptive radiation represents evolution of new forms in several directions from the common ancestral type. In 1931, Darwin got an opportunity to travel by H M S Beagle for a voyage of world exploration. Beagle sailed to the Galapagos islands; here he found a living laboratory of evolution. The common birds of Galapagos islands, the finches were markedly different from the finches of main land. The closely related species of finches had beaks of different shapes, sizes and adapted for feeding on completely different diet showing adaptive radiation.
Question 2
4 / -1

__________ are formed when speciation occurs in geographically separated regions.

A
Paraspecies

B
Sympatric species

C
Allopatric specie

D
Sibling species

Solution

Allopatric speciation occurs when the specie that has been geographically isolated from the parent specie, evolves in the geographical isolation. So, speciation in geographically separated regions forms allopatric species.
Question 3
4 / -1

At particular locus, frequency of 'A' allele is 0.6 and that of 'a' is 0.4. What would be the frequency of heterozygotes in a random mating population at equilibrium?

A
0.16

B
0.48

C
0.35

D
0.24

Solution

As per Hardy-Weinberg equation:
The, heterozygous frequency is
P² + 2pq + q² = 1
p = dominant allele frequency
q = recessive allele frequency
p² = homozygous genotype
2pq = heterozygous recessive genotype
q² = homozygous recessive genotype
in question, p = 0.6 and q = 0.4
= 2pq = 2 × 0.6 × 0.4 = 0.48
Question 4
4 / -1

Select the correct statement:

A
All mammals except whales and camels have seven cervical vertebrae

B
Fitness is the end result of the ability to adapt and get selected by nature

C
Mutations are random and directional

D
Darwinian variations are small and directionless

Solution

According to Darwin, fitness is the ability of an individual to survive and reproduce in its own environment. This fitness depends on the number of offspring it produces comparing to the other individuals of its own species. So, natural selection is based on Survival of the fittest. Individuals that are able to reproduce more than others are naturally selected first because these individuals will produce large number of off-springs thus will pass on more of their genetic material than the less fit individuals.
Question 5
4 / -1

DNA replication is

A
Semicontinuous, conservative

B
Semiconservative, semi-discontinuous

C
Conservative, continuous

D
Semiconservative, continuous

Solution

DNA replication is defined as semiconservative because one strand of the double helix(parent) is conserved in every new DNA molecule. The replication is discontinuous because the leading strand gets synthesized continuously while the lagging strand gets synthesized discontinuously.
Question 6
4 / -1

There are special proteins that help to open up DNA double helix in front of the replication fork in Prokaryotes by breaking the hydrogen bonds between the strands.

A
DNA helicase

B
DNA polymerase I

C
DNA ligase

D
DNA topoisomerase

Solution

DNA helicase, often referred to simply as gyrase, is an enzyme that relieves strain while double-stranded DNA is being unwound by helicase. This causes the supercoiling of DNA.
Question 7
4 / -1

The theory where ratio between the number of X-chromosomes and number of complete sets of autosomes will determine the sex is known as

A
Chromosome theory of sex determination

B
Genic balance theory of sex determination

C
Hormonal balance theory of sex determination

D
Environmental sex determination theory

Solution

The theory of genic balance given by Calvin Bridges (1926) states that instead of XY chromsomes, sex is determined by the genic balance or ratio between X-chromosomes and autosome genomes.
Question 8
4 / -1

According to the current ideas concerning protein synthesis

A
transfer RNA molecules specific for particular amino acids are synthesized along a messenger RNA template in the cytoplasm.

B
amino acids line up with their mRNA codons on the ribosomes and are then linked together by transfer RNA.

C
enzymes that catalyze protein- synthesizing reactions in the cytoplasm are transcribed from activator genes.

D
messenger RNA, synthesized on a DNA template in the nucleus, provides information that determines the sequence in which amino acids will be linked during translation.

Solution

Protein synthesis is a multistep process which involves transcription of mRNA from nuclear DNA template. After processing of the mRNA (removal of introns/ non-coding regions) the mature mRNA is used as input to translation.
Question 9
4 / -1

During transcription holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle like structure at the point. What is that sequence called

A
CAAT box

B
Shine dalgaro sequence

C
AAAT box

D
TATA box

Solution

TATA box is present in eukaryotic promoter region. It has a resemblance with pribnow box of prokaryotes. TATA box was identified by Dr. Hogness and so it is also called as Hogness box. During the process of transcription the RNA polymerase binds to TATA box due to which DNA assumes a saddle like structure at this place.

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Biology Test 33

Result

Biology Test 33

Score

-

Rank

-

SHARING IS CARING

Question 1

adaptive radiation

seasonal migration

brood parasitism

connecting links

Solution

Question 2

Paraspecies

Sympatric species

Allopatric specie

Sibling species

Solution

Question 3

0.16

0.48

0.35

0.24

Solution

Question 4

All mammals except whales and camels have seven cervical vertebrae

Fitness is the end result of the ability to adapt and get selected by nature

Mutations are random and directional

Darwinian variations are small and directionless

Solution

Question 5

Semicontinuous, conservative

Semiconservative, semi-discontinuous

Conservative, continuous

Semiconservative, continuous

Solution

Question 6

DNA helicase

DNA polymerase I

DNA ligase

DNA topoisomerase

Solution

Question 7

Chromosome theory of sex determination

Genic balance theory of sex determination

Hormonal balance theory of sex determination

Environmental sex determination theory

Solution

Question 8

transfer RNA molecules specific for particular amino acids are synthesized along a messenger RNA template in the cytoplasm.

amino acids line up with their mRNA codons on the ribosomes and are then linked together by transfer RNA.

enzymes that catalyze protein- synthesizing reactions in the cytoplasm are transcribed from activator genes.

messenger RNA, synthesized on a DNA template in the nucleus, provides information that determines the sequence in which amino acids will be linked during translation.

Solution

Question 9

CAAT box

Shine dalgaro sequence

AAAT box

TATA box

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.