CSIR NET Life Sciences Mock Test - 5 - CSIR NET Life Science MCQ

Given

Average of 30 numbers = 15.5

Average of first 15 numbers = 8

Average of last 16 numbers = 22.5

Calculation:

Sum of all 30 numbers = 15.5 × 30

= 465

Sum of first 15 numbers = 15 × 8

= 120

Sum of last 16 numbers = 22.5 × 16

= 360

Fifteenth number = Sum of first 15 numbers + Sum of last 16 numbers - Sum of 30 numbers

= 120 + 360 - 465

= 480 - 465

= 15

∴ The value of the 15th number is 15.

Given:

Percentage of passengers travelling from Haridwar to Delhi, Rishikesh, Jaipur and Amritsar respectively , and
Total numbers of passengers

Total percentage of passengers travelling from Haridwar to Delhi, Rishikesh, Jaipur and Amritsar
So the number of passengers travelling from Haridwar to Delhi, Rishikesh, Jaipur and Amritsar of

Average

∴ The average number of passengers travelling between Haridwar to Delhi, Rishikesh, Jaipur and Amritsar is 225.

Given:

Percentage of passengers travelling from Haridwar to Dehradun

Percentage of passengers travelling from Haridwar to Jaipur

Required percentage

∴ Required percentage will be .

Sum of the odd place digits

Sum of the even place digits

Difference between the sum of the odd place digits and sum of the even place digits,

We can see only for

Value of

Given series: JMEV WBFJ SKIC DNPO HQTU

On replacing the consonants with their successors as per the English alphabetical series, we get,

KNEW XCGK TLID EOQO IRUU

Clearly, two words have more than one vowel in them.

Given,

The above sentence is given by Gause’s competitive exclusion principle. It states that two species having the same resources cannot live together at constant population values. The inferior species will be eliminated with time due to natural selection.

DNA contains the blueprints for all of the proteins in our bodies, neatly packed in a double helix. Transcription and translation are the processes that turn DNA into proteins, and they take place in distinct parts of the cell. The first step, transcription, takes place in the nucleus, which is where the DNA is stored.

The ciliary body is a circular structure that is an extension of the iris, the colored part of the eye. The ciliary body produces the fluid in the eye called aqueous humor. It also contains the ciliary muscle, which changes the shape of the lens when your eyes focus on a near object.

Vohwinkel’s syndrome is a skin disease caused by a disorder in the gap junction. It is characterized by thick calluses in the palms of hands and feet. This disease is seen in the infant stages or early childhood.

Wobble Hypothesis is degeneracy of the 3rd base.

Usually, one anticodon recognizes and reads a single codon, but sometimes it may recognize more than one codon this phenomenon is called Wobbling. It generally occurs for the 3'-nucleotide of codon and the 5'-nucleotide of the anticodon. For example, according to wobble base pairing anticodon GAG can recognize two codons i.e. CUC and CUU, and both stand for leucine. Wobbling occurs due to the degeneracy of the 3rd base of the codon. This third base is called ''Wobbly base"

Below is the table of the wobble base pairs:

Hence, the correct option is (B).

An ion exchanger is usually a three - dimensional network or matrix that contains covalently linked charged groups.

Ion exchange chromatography resins are composed of positively or negatively charged functional groups that are covalently bound to a solid matrix.

Reporter gene fusion including introns would give the most precise and accurate information about where and when a given gene is expressed. Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce protein as the end product. A reporter gene (often simply reporter) is a gene that researchers attach to a regulatory sequence of another gene of interest in bacteria, cell culture, animals, or plants. Such genes are called reporters because the characteristics they confer on organisms expressing them are easily identified and measured, or because they are selectable markers. Reporter genes are often used as an indication of whether a certain gene has been taken up by or expressed in the cell or organism population.

A transposable element (TE) is a DNA sequence that can change its position in a genome, and often results in the duplication of the same genetic material.

There are two types of TEs:

(i) Retrotransposons

(ii) DNA transposons

Retrotransposons employ reverse transcription, whereby DNA sequences are first transcribed into RNA and then back into identical DNA sequences which are inserted in the genome. On the other hand, DNA transposons do not involve RNA intermediate, rather they encode transposase enzyme, which helps in their insertion or excision.

Stevia: Stevia is a sugar substitute made from the leaves of the stevia plant. It's about 100 to 300 times sweeter than table sugar, but it has no carbohydrates, calories, or artificial ingredients.

Starch: Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants as energy storage. It is the most common carbohydrate in human diets and is contained in large amounts in staple foods like potatoes, maize (corn), rice, wheat, and cassava. Pure starch is a white, tasteless, and odourless powder that is insoluble in cold water or alcohol. 

Cellulose: A complex carbohydrate that is the chief component of the cell walls of plants, composed of a long chain of repeating glucose units. Cellulose can only be digested by bacteria, which often grow symbiotically in the guts of animals like ruminants and termites.

Lactose: Lactose is the principal sugar (or carbohydrate) naturally found in milk and dairy. Lactose is composed of glucose and galactose, two simpler sugars used as energy directly by our body. Lactase, an enzyme, splits lactose into glucose and galactose.

Mutation in single nucleotide base of a DNA segment is called as a point mutation. It occurs by substitution or frameshift mutation. Exchange of one nitrogenous base for another base is called as substitution; option C is correct. The transition is the substitution of one type of base by other of its own type (purine –purine and pyrimidine –pyrimidine). Substitution of purine base for a pyrimidine base or substitution of pyrimidine base for a purine base is called as transversion. The gene mutations that alter the base sequence of the whole genetic frame from the point of the mutation are called frame shift mutations. Here, the reading frame of the base sequence is shifted forward (due to insertion of one or more nucleotide base) or in the backward direction (due to deletion of one or more nucleotide base); options A and B are correct. Duplication is the presence of extrachromosomal segment which is attached to the normal homologous chromosome causing duplication of a set of genes in the same chromosome; thus it is not a point mutation. 

The key feature of metaphase is the attachment of spindle fibers to kinetochores of chromosomes. Kinetochores are disc-shaped structure at the surface of the centromeres. These structures serve as the site of attachment of spindle fibres to the chromosomes that are moved toward poles.

The basic components of proteins is Amino Acids.

• Proteins are made up of Amino Acids, essentially they are the building blocks of proteins.
• Each protein is made from a combination of different amino acids
• There are about 21 amino acids in total.
• Each acid is made up of carbon, hydrogen, oxygen and nitrogen although other elements might also be present in different acids.

Development includes all the changes undergone by a living plant from seed emergence to death. Dedifferentiation is regaining the lost capacity of cells or tissues of plants to divide under special conditions. Redifferentiation is the further maturation of dedifferentiated cells thereby specializing for a particular function. Differentiation is the division and growth of cells in order to mature.

Macromolecule chitin is nitrogen containing polysaccharide.

Chitin is a long-chain polymer of a N-acetylglucosamine. It is a nitrogen containing polysaccharide and a derivative of glucose. It is a characteristic component of the cell walls of fungi, the exoskeletons of arthropods such as crustaceans and insects, the radulae of molluscs, and the beaks and internal shells of cephalopods, including squid and octopuses. 

Desert lizard has the ability to keep the constant body temperature  statements is incorrect. 

Among the above-given sentences, the desert lizard has the ability to keep a constant body temperature is an incorrect statement. This is so because lizards are ectotherms, cold-blooded whose temperature changes as per the temperature of surroundings. 

Golgi apparatus, also known as the Golgi body, is a cell membrane that is a part of the endomembrane system in the cytoplasm. It is a 'membrane-bound organelle' of the eukaryotic cell which is made up of a series of 'flattened, stacked pouches’ called 'cisternae'. This organelle serves as a 'primary packaging area' for molecules that will be distributed throughout the cell. It packs the protein into membrane-bound vesicles inside the cell before sending it to its destination. 

Fermentation is where microorganisms produce a beneficial and desirable change in food. The process of fermentation is commonly deployed in the alcohol industry. Alcoholic fermentation or ethanol fermentation is a biological method wherein the sugar gets transformed into carbon dioxide and alcohol.

Oxygen is not a prerequisite, hence is an anaerobic process and is typically carried out by yeasts. The by-products of this process of fermentation are alcohol, carbon dioxide, water, and heat. The process of ethanol fermentation has been in use for millennia.

The process of fermentation occurs in anaerobic conditions, in the absence of oxygen, and in the presence of beneficial microbes that gain energy through fermentation. Even when there is sufficient oxygen, if there is enough sugar, some of the yeast cells (Saccharomyces cerevisiae) opt for fermentation over aerobic respiration.

The process of fermentation results in microbes disintegrating sugars into alcohols and acids, thus making food nutritious and increasing its shelf life. The products of fermentation render enzymes required for digestion. Food that is fermented comprises enzymes needed to break it down.

So, only statement a is correct.

If the physical change accompanying the reaction is heat output, the biosensors are referred to as calorimetric biosensors. In potentiometric biosensors, changes in the distribution of charges causes an electrical potential to be produced. Optical biosensors are those in which light output during the reaction is the physical change. In amperometric biosensors, movement of electrons produced in a redox reaction is the physical reaction.

Steroids are hormones derived from cholesterol which carry messages by endocrine stimulation. Steroids regulate sexual differentiation, pregnancy, carbohydrate metabolism, and excretion of sodium and potassium ions.

The steroid hormones are synthesized in the adrenal cortex, the gonads, and the placenta; are all derived from cholesterol and many are of clinical importance. Steroid hormones are synthesized in the mitochondria and smooth endoplasmic reticulum.

According to Lamarck, the causes of evolution are the innate tendency of organisms to evolve towards greater complexities and inheritance of acquired characters.

During the lifetime of an organism new characters develop due to interval vital forces, the effect of environment, new needs, and use and disuse of organs.

These acquired characters are inherited from one generation to another. By continuous inheritance through many generations, these acquired characters tend to make a new generation quite different from its ancestors resulting in the formation of new species.

Zaug, Thomas Cech and Altman proved that RNA molecules have enzymatic activity. Ribozymes also called as RNA enzymes were able to replicate or produce primordial RNA. It was also believed that earth was an ‘RNA world’ about 4 billion years ago.

The materials or substances occurring in nature that exist without the actions of humankind are known as natural resources. These resources can be conserved by using them wisely.

conservation, study of the loss of Earth's biological diversity and the ways this loss can be prevented. Biological diversity, or biodiversity, is the variety of life either in a particular place or on the entire planet Earth, including its ecosystems, species, populations, and genes.

All the 4 options refer to approaches of early humans that have benefitted society. However, the domestication of dog and cow and the artificial selection of wheat as a crop have used the principle of variation and selection of traits best suitable for a particular task.