CSIR NET Life Sciences Mock Test - 8 - CSIR NET Life Science MCQ

Given,

The average salary per head of all the employees of an institution

The average salary of 12 officers Rs.

The average salary per head of the rest Rs.

Let the total number of employees

According to the given,

∴ The total number of employees in the institution is 1032.

The area of the rectangle is 144 cm² and the sides are in the ratio 4:9.
Let the length be 4x and the breadth be 9x. 
Area of a rectangle = length × breadth gth

Therefore, the length cm and the breadth =18 cm
Perimeter of a rectangle =2 (Length Breadth)

Perimeter 

Perimeter  Perimeter cm

The formula for Arithmetic Sequence:
a_n = a₁ + (n – 1)d
According to the question
q = p + (3 - 1)d
⇒ q = p + 2d    ----(1)
And 3 = p + (5 - 1)d
⇒ 3 = p + 4d    ----(2)
Solving (1) and (2), we get
q = 3 - 2d
and p = 3 - 4d      [from (2)]
According to the question pq is minimum
= (3 - 4d) (3 - 2d) is minimum
= (9 - 18d + 8d²) is minimum
Differentiation the above equation with respect to d is 0
⇒ -18 + 16d = 0
⇒ d = 9/8
∴ The value of d is 9/8.

Given:

Anuja owns or of a property

30% of Anuja's owns property worth Rs. 125000

Let the worth of the property be 'x'.

According to the question,

∴ The value of 45% of the total property will be Rs. 281250.

Given:

ABC is a triangle and the ratio of their angle is 1 ∶ 3 ∶ 2.

Concept:

The sum of the angles of a triangle = 180°

Calculation:

According to the question,

The ratio of the angles of a triangle = 1 ∶ 3 ∶ 2

Let the angles of the triangle be x, 3x and 2x respectively.

x + 3x + 2x = 180°

⇒ 6x = 180°

⇒ x = 30°

⇒ 3x = 3 × 30° = 90° and 2x = 2 × 30° = 60°

The angles of triangle ABC are 30°, 90° and 60°.

Sum of the largest and smallest angle of triangle = 90° + 30° = 120°.

∴ Sum of the largest and smallest angle of triangle is 120°.

In 200 mixture, milk  = liter

Water in the mixture=200-160 = 40 liter

Let the quantity of mixture is taken out = 5x

Then,  

480 - 12x = 350 - 7x 

5x = 130

x = 26 

Quantity of mixture taken out = 130 liter

Given,
Probability of Solving the problem by first person = 1/3

Probability of Solving the problem by second person = 1/4

Probability of Solving the problem by third person = 1/5

Probability of Not Solving the problem by first person  

Probability of not Solving the problem by second person 
= 3/4
Probability of not Solving the problem by third person  

So, The probability of none solving the problem  

A male can be a cricketer or an actor, but an actor cannot be a cricketer.

Thus, the Venn diagram that best describes the above relationship is:

Biodiversity forms the backbone of viable ecosystems on which we depend on for basic necessities. These ecosystem services play an important role in the functioning of our climate and in both air and water quality.

Mutations can involve the replacement of one base pair with another (substitution mutation) or the addition or deletion of one or more base pairs (insertion or deletion mutations).

In honeybee, ant and wasp, the sperms are produced without involving meiosis. In these organisms, the sex is determined by ploidy of an organism. In this, the female is diploid and is derived from fertilized egg. Whereas the male is haploid and sperm production occurs by mitosis (equational division) and not meiosis (reductional division).

Decomposers are the organisms called those who are  responsible for the break down complex organic matter into inorganic substances. 
The organisms that are responsible for the break down complex organic matter (dead or decaying organisms) into inorganic substances are called decomposers (detritivores). The decomposers or detritivores may include invertebrates, fungus or bacteria. 

In Bacteria, when many flagella present only at one pole, are known as Lophotrichoous.

Flagella: It is a slender threadlike structure, especially a microscopic part that enables many protozoa, bacteria, spermatozoa, etc. to swim.

Parts of flagella: Bacterial flagellum is composed of three parts – filament, hook and the basal body.

Based on the number and placement of flagella on the cell, there are four types of flagellar arrangements. They are:

Merodiploid is a bacterial cell that is mostly hapoid, but is diploid for some regions of the genome. It is also known as partial diploid.

A merodiploid is a partially diploid bacterium, which has its own chromosome complement and a chromosome fragment introduced by conjugation, transformation or transduction. It can also be defined as an essentially haploid organism that carries a second copy of a part of its genome.

Niche is a specific physical space occupied by an organism as well as its functional role in ecosystem. It includes the behavioural characteristics of organisms. The fundamental niche is always larger than realized niche.

In a biosensor, when the changes in the distribution of charges cause an electrical potential to be produced. Such biosensors are referred to as potentiometric biosensors. In the same way, if the effects are due to the mass of the reactants or products, then the biosensor is referred to as a piezo-electric biosensor.

Asexual Reproduction: It is the process in which a new individual is formed by the involvement of a single parent with or without the involvement of the gamete formation. The individuals produced are genetically and morphologically similar. It occurs in unicellular organisms where cells divide by mitotic division and no fertilization takes place. The division occurs very rapidly.

Types Of Asexual Reproduction

Binary Fission: It is seen in amoeba and euglena. The parent cell undergoes mitosis and increases in size. The nucleus also divides. Two identical daughter cells are obtained, each containing a nucleus. Prokaryotes like bacteria majorly reproduce by binary fission.

Budding: In this, the offspring grows out of the body of the parent. It remains attached to the parent until it matures. After maturation, it detached itself from the parent and lived as an individual organism. This form of reproduction is most common in Hydras.

Fragmentation: In some organisms like Planarians, when the body of an organism breaks into several pieces each piece grows into an individual offspring. This is known as fragmentation. It can occur through accidental damage by predators or otherwise, or as a natural form of reproduction. In a few animals such as seastar, a broken arm grows into a complete organism.

Regeneration: It is a modified form of fragmentation and occurs mostly in Echinoderms. When a part of an organism, like an arm, detaches from the parent body, it grows into a completely new individual. 

Parthenogenesis: This is a form of asexual reproduction where the egg develops without fertilization. This process occurs in bees, wasps, ants, aphids, rotifers, etc. Ants, wasps, and bees produce haploid males. Parthenogenesis has been observed in a few vertebrates such as hammerhead sharks, Komodo dragons, and blacktop sharks when the females were isolated from the males.

Phytochrome is involved in photoperiodism.

Phytochrome is a photoreceptor molecule that mediates several developmental and morphogenetic responses of plants to light. This is called photoperiodism. Borthwick, Hendricks, and Parker in 1952 discovered phytochrome, which is a pigment that received light existed in two interconvertible forms active form and inactive form.

DNA replication is the process by which the DNA duplicates itself. At the start of the DNA replication, the hydrogen bonds between the nucleotides of two strands break by the action of enzyme helicase. RNA primer attaches on the template strand which provides a 3' end for DNA polymerase to work on. The DNA is synthesized by DNA polymerase in the 5'-3' direction on leading strand by DNA polymerase. When the DNA polymerase works in the opposite direction on lagging strand it synthesizes discontinuous short DNA segments known as Okazaki in 3'-5' direction. DNA ligase is the enzyme which helps in joining the Okazaki segments and forms the continuous complimentary strand of the daughter DNA.

Proteins are liable to saturate, respond to inhibitors, under hormonal regulation and highly selective, thus, are responsible for facilitated diffusion.

Facilitated diffusion is the passive movement of molecules along the concentration gradient. It is a selective process, i.e., the membrane allows only selective molecules and ions to pass through it. It, however, prevents other molecules from passing through the membrane.

Schwann cells secrete a myelin sheath.

The myelinated nerve fibres are enveloped with Schwann cells, which form a myelin sheath around the axon. The gaps between the two adjacent myelin sheaths are called Nodes of Ranvier. 

Humans consist of two similar chromosomes(XX) for the female sex chromosomes and two dissimilar chromosomes (XY) for males.

Interdemic selection: A trait considered to be harmful to the individuals within the population. However, would be beneficial to the population as a whole; such a trait would thus be selected for until every individual within the population has the trait (i.e, the trait becomes fixed).

• Artificial selection: The selective breeding by humans towards a desired trait in a plant, animal, or other organisms which is of value to humans.
• Backward selection: A situation in which the best parents in a generation are chosen for breeding based on their progeny’s performance.
• Genic selection: A type of natural selection that acts upon individual genes and alleles within an organism's genome. It occurs whenever a gene or allele reproduces at a rate different from the organism which carries it.

'Palade particles' is another name for ribosomes.

• Ribosomes are non-membrane bound organelles and granular structures that was discovered by George Palade in 1953.
• They are composed of ribonucleic acid (RNA) and proteins.
• Ribosomes are protein synthesizers of a cell and they are found in both Prokaryotic and Eukaryotic cells.

Aesthetic value provides physical, intellectual and emotional satisfying for humans. Nearly everyone enjoys wildlife and joy makes our lives good lives. It will reduce the stress and give a great pleasure to eyes.

Following are the properties which a biosensor should possess:

If the biosensor used in invasive, the probe must be tiny and biocompatible, having no toxic or antigenic effects.

The biosensor should be cheap, small, portable, and capable of being used by semi-skilled operators.

If the traditional methods used are encouraged and the decentralization of laboratory testing is discouraged, then there is no use of producing more biosensors. Thus, there should be a market for biosensors.

“The specificity of substrate binding is mediated by the spatial arrangement of atoms in an enzyme’s substrate binding site as well as the substrate.” This is a property of the active site of the enzyme.

The identity and chemical properties of a compound can be determined by the number of positively charged protons it contains. For example, hydrogen has a single proton, and helium has two.

'In multicellular organisms, cell communicate using hormones' statements is true about cell signaling.

Cells typically communicate using chemical signals. These chemical signals, which are proteins or other molecules produced by a sending cell, are often secreted from the cell and released into the extracellular space. There, they can float – like messages in a bottle – over to neighboring cells.

Nucleolus is the site for synthesis of Ribosomal RNA.

• Ribosomal RNA (rRNA) is a molecule in cells that is part of protein-building organelles called ribosomes and is exported to the cytoplasm to help translate the information contained in messenger RNA (mRNA) to proteins. 
• The encoded rRNAs are of different sizes, differentiated into large or small. Each ribosome contains at least 1 large rRNA and at least 1 small rRNA. 
• In the nucleolus, large and small rRNAs combine with ribosomal proteins to form large and small ribosomal subunits (eg, 50S and 30S in bacteria, respectively).

Flowers contain the plant’s reproductive structures. A typical flower has four main parts - or whorls - known as the calyx, corolla, androecium, and gynoecium. The outermost whorl of the flower has green, leafy structures known as sepals. The sepals, collectively called the calyx, help to protect the unopened bud.