CSIR NET Life Sciences Mock Test - 9 - CSIR NET Life Science MCQ

There are total 14 rhombuses in the following figure.

After arranging the words in a meaningful sequence, we get
Root  Stem Leaf  Flower Fruit
The correct order is 4,3,1,5,2.

Given:
SP while earning profit = SP while incurring a loss

Formula:
Selling Price = Cost Price + Profit
Selling Price = Cost Price - Loss

Calculation:
Let the cost price be = a
1754 - a = Profit
a - 1492 = Loss
As per the question;
1754 - a = a - 1492
⇒ 1754 + 1492 = 2a
⇒ 3246 = 2a

⇒ a = 1623
∴ The cost price of article Rs. 1623.

The followed pattern is:

Thus, is the correct alternative.

Given:

Mean: Median = 4:3

Mode = 63

Formula used:

Mode = 3 × Median −2 × Mean

Let the mean and median of the set of observations is 4x and 3x.

∴ The mean of this set of observations is 252.

Given:
Total surface area of a cylinder

The sum of the radius and height of the cylinder

= 35
It means,

Therefore,
Circumference of cylinder

Given,
Length (l) = 15 cm
Breath (b) = 12 cm
Let the Height be h.
Sum of Area of four walls = Sum of area of floor and ceiling

Given:

Where, A is Amount, P is Principal, R is rate of interest, and t is time in years

Given

In a family, the father has a blood group ‘A’ and the mother has a blood group ‘B’, Children show 50% probability for a blood group “AB” indicate that either of the parent is heterozygous.

The presence of two different alleles at a particular gene locus. A heterozygous genotype may include one normal allele and one mutated allele or two different mutated alleles (compound heterozygote).

An organism that has superoxide dismutase but lacks catalase is; Aerotolerant anaerobe.

Aerotolerant anaerobe can synthesize superoxide dismutase but does not catalase for protection against ROS and this is because Aerotolerant anaerobes can survive in the absence or presence of oxygen.

An aerotolerant organism is tagged an anaerobe because it does not make use of oxygen during oxidation ( i.e. to produce energy ).

Therefore,we can conclude that An organism that has superoxide dismutase but lacks catalase is Aerotolerant anaerobe.

Poisonous fluid present in nematocyst of Hydra is Hypnotoxin.

The Hypnotoxin present in Nematocytes is injected with the help of the threaded tube. This thread tube acts like a piercing needle. The lower end of the tube is enlarged to form butt which bears spines in some cnidoblasts.

The type of natural selection where more individuals acquire a value other than the mean character value is known as directional.

Natural selection can lead to 3 possibilities:

• Stabilizing - More individuals acquire the mean character value, getting a higher and narrower peak in the distribution curve.
• Directional - More individuals acquire a value other than the mean character value, causing a shift in the distribution curve.
• Disruptive - More individuals acquire peripheral character value at both ends of the distribution curve.

The tRNA synthetase enzyme recognizes a specific amino acid and its cognate tRNA molecules. There are 20 different enzymes, which are categorized into 2 classes.

The genetic composition of an organism is known as genotype.

The genotype is the genetic makeup of a cell, an organism, or an individual usually with reference to a specific characteristic under consideration. For example, TT or Tt or tt is the genotype for height of a plant.

Ultraviolet radiations cause mutations due to formation of thymine dimers/ thymidine.

The signature mutation caused by ultraviolet light is a CC to TT mutation (C=cystosine T=thymidine), caused when a CC dimer is mispaired with two adenine bases during replication. Because of these mutations, the connection between ultraviolet damage to DNA and cancer is quite clear.

Ribonucleic acid (RNA) is a linear molecule composed of four types of smaller molecules called ribonucleotide bases: adenine (A), cytosine (C), guanine (G), and uracil (U). RNA is often compared to a copy from a reference book, or a template, because it carries the same information as its DNA template but is not used for long-term storage.

There are three types of cell signaling pathways – autocrine, paracrine and endocrine. Cells communicate with each other through extracellular messenger molecules. Based on the distances these messenger molecules travel, the signaling pathways differ.

The only organism in which systematic gene targeting has been achieved is yeast .The only organism in which systematic gene targeting has been achieved is the yeast Saccharomyces Cerevisiae. Its genome contains about 6000 open reading frames. 

Cleavage in human is Unequal. 

The cleavage in which the egg is divided unequally is called an unequal cleavage. Humans and Marsupials are an example of unequal holoblastic cleavage. The mode of cleavage is determined by the amount of yolk and it’s distribution. The first cleavage occurs in human zygotes about 30 hours after fertilization. It is holoblastic (complete) and gives rise to the blastomeres; one of which is slightly larger than the other.

Holoblastic: The cleavage in which the segmentation line passes through the entire egg, dividing it completely. It occurs in alecithal, microlecithal and mesolecithal eggs. Holoblastic cleavage is of two types:

Equal Holoblastic: In this process, the egg is divided into two equal halves.

Meroblastic cleavage: The lines of segmentation do not completely pass through the egg and remain confined to a part of the egg. Such type of cleavage is found in megalecithal eggs as the yolk provides resistance to the cleavage. Insects, birds, reptiles are examples of meroblastic cleavage.

Superficial cleavage occurs in centrolecithal eggs of insects. 

Scavengers are the animals that feed on the dead and rotting organisms. Scavengers provide an important service to the ecosystem by removing disintegrating organisms and acting as an innate sanitation system. Scavengers assist conserve energy and nutrients received from rotting flesh within the top trophic levels and thus are capable of transferring the energy and nutrients further away from the source of the carrion.

In Counter immunoelectrophoresis, electrophoresis will drive the antibody and antigen toward each other

Counter Current Immunoelectrophoresis is a modification of immunoelectrophoresis in which antigen and antibody move in opposite directions and form precipitates in the area where they meet in concentrations of optimal proportions. It is also referred to as countercurrent or crossed-over immunoelectrophoresis.

Counter-current immunoelectrophoresis depends on the movement of antigens toward the anode and of antibodies towards the cathode through the agar under the electric field. The test is performed on a glass slide in an agarose gel of high electro-endosmotic flow. A pair of wells is punched out where one well is filled with antigen and the other with the antibody. Electric current is then passed through the gel. The migration of antigen and antibody is greatly facilitated under the electric field, and the line of precipitation as precipitin arcs is made visible in 30–60 minutes, which indicates a positive reaction.

The Etr1 gene in plants encodes for a receptor of the ethylene gas (C₂H₂). Ethylene is a plant hormone that regulates a variety of developmental processes such as seed germination and fruit ripening.

Protista are not multicellular eukaryotic organisms.

The Protista is a large complex grouping of mostly unicellular eukaryotic organisms. They are morphologically diverse and can be found in most terrestrial, aquatic, and marine habitats as free-living forms and as parasites of other protists, fungi, and plants and animals.

A cross is made between F₁ individual and homozygous recessive individual is called Test cross.
When a heterozygous round seeded plant(Rr) is crossed with homozygous wrinkled seeded plant (rr), in the next generation, 50% progeny are heterozygous round (Rr) and 50% progeny are homozygous wrinkled (rr). The ratio between heterozygous round(Rr) and homozygous wrinkled (rr) is 1 : 1. It is called Test cross.

Only statement 3 is correct that, the resolution is the regeneration of duplex DNA molecule.
In the process of homologous recombination, DNA molecules are regenerated by the process of genetic exchange. This is known as the process of resolution.
Homologous recombination can be divided into three key steps: strand exchange, branch migration and resolution. The identification of a protein complex that catalyses branch migration and Holliday junction resolution argues that the mechanism of homologous recombination is conserved from bacteria to man.

Proteins are made up of amino acids. The amino acids are linked together by peptide bonds to form a protein.
The amino acids consist of an amine group made up of nitrogen and hydrogen and the carboxyl group at the end and a side chain of R group which is specific to a particular amino acid. Carboxyl is formed by carbon, oxygen, and hydrogen (COOH).

Plant cells lack a centrosome and lysosomes, while animal cells do. Animal cells lack a cell wall, chloroplasts, and other specialized plastids, as well as a big central vacuole, but plant cells do.
The centrosome is the primary microtubule-organizing centre (MTOC) in animal cells, and so it regulates cell motility, adhesion and polarity in interphase, and facilitates the organization of the spindle poles during mitosis.

When B cells switch from producing IgM or IgD to IgG immunoglobulins, the change occurs in the genome as the genes encoding the constant regions for Igm and IgD are deleted independently of the RAG proteins.

After immunization or infection, activated naïve B cells can switch from expressing IgM and IgD on their surface to expressing IgG, IgE or IgA. This isotype/class switch changes the effector function of the antibody, and improves its ability to eliminate the pathogen that induced the response.

NGT that has been issuing multiple directives is a quasi-judicial body works on the principle of natural justice act as 'fast track court'.

The NGT was established on October 18, 2010 under the National Green Tribunal Act 2010, passed by the Central Government. The stated objective of the Central Government was to provide a specialized forum for effective and speedy disposal of cases pertaining to environment protection, conservation of forests and for seeking compensation for damages caused to people or property due to violation of environmental laws or conditions specified while granting permissions. It is a Quasi-Judicial body. The NGT is not bound by the procedure laid down under the Code of Civil Procedure, 1908, but is guided by principles of natural justice. It acts a fast track court.