1. Which among the following is correct statement about solubility of “Lipids”?
[A] They dissolve in water but are insoluble in organic solvents
[B] They do not dissolve in water but are soluble in organic solvents
[C] They dissolve in both water and organic solvents
[D] They do not dissolve in either water or organic solvents
Show Answer
Correct Answer: B [They do not dissolve in water but are soluble in organic solvents]
Notes:
Lipids are categorised within a group of naturally occurring molecules, including fats, waxes, sterols, fat-soluble vitamins and others. They are hydrophobic or non-polar, which explains why they’re not soluble in water, a polar substance, but are soluble in organic, non-polar solvents.
2. The reverse osmosis is the process of forcing a solvent from a region of high solute concentration through a membrane to a region of low solute concentration by applying a pressure on ________?
[A] Concentrated solution
[B] Dilute solution
[C] Membrane
[D] None of the above
Show Answer
Correct Answer: A [Concentrated solution]
Notes:
This process requires that a high pressure be exerted on the high concentration side of the membrane.
3. Which among the following is true regarding fraternal twins?
[A] They may look similar but are not genetically identical
[B] They are exactly similar but are not genetically identical
[C] They are exactly similar and are genetically identical
[D] None of the above
Show Answer
Correct Answer: B [They are exactly similar but are not genetically identical]
Notes:
Twins are two offspring produced by the same pregnancy. Twins can be either monozygotic (‘identical’), meaning that they develop from one zygote, which splits and forms two embryos, or dizygotic (‘fraternal’), meaning that each twin develops from a separate egg and each egg is fertilized by its own sperm cell.
4. Which among the following test is most suitable to judge paternity ?
[A] Blood Grouping
[B] Tissue Culture
[C] DNA Test
[D] Genetic Codes
Show Answer
Correct Answer: C [DNA Test]
Notes:
DNA test is most suitable to judge paternity. It looks at specific locations of a person’s genome, in order to find or verify
ancestral genealogical relationships. It can also be used to estimate the ethnic mixture of an individual.
5. Which among the following is correct about biocenosis?
[A] The study of energy transformations in the living systems
[B] Community of organisms occupying an area
[C] Study of the parts of an ecosystem with specific species
[D] A kind of abnormality related to organism living in a particular habitat
Show Answer
Correct Answer: B [Community of organisms occupying an area]
Notes:
The term Biocenosis was coined by Karl Mobius in 1877. It describes the interacting organisms which are living together in a habitat or biotope. The use of this term has declined in the 21st Century.
6. The nutritional supplements Spirulina, Chorella and the Vitamin-C supplement, Dunaliella are actually :
[A] Algae
[B] Lichens
[C] Probiotics
[D] Bryophytes
Show Answer
Correct Answer: A [Algae]
Notes:
The nutritional supplements Spirulina, Chorella and the Vitamin-C supplement, Dunaliella are actually unicellular algae that are commercially produced worldwide. These algae are concentrated sources of carotenoids (especially provitamin A carotenoids) and other nutrients.
7. Saffron’ is obtained from which among the following parts of the plant?
[A] Stigma
[B] Anther
[C] Stamen
[D] Pollen
Show Answer
Correct Answer: A [Stigma]
Notes:
Saffron is a spice derived from the flower of Crocus sativus, commonly known as the “saffron crocus”. It is mainly grown in cold regions. Saffron’ is obtained from the stigma of the plant.
8. The mosquito fern or Azolla is used as a biofertiliser because it__:
[A] Multiplies very fast to produce massive biomass
[B] Has association of nitrogen-fixing Rhizobium bacteria
[C] Has association of nitrogen fixing bluegreen algae
[D] Has association of mycorrhiza
Show Answer
Correct Answer: C [ Has association of nitrogen fixing bluegreen algae]
Notes:
Azolla, also known as mosquito fern, is used as a biofertilizer because it has a symbiotic relationship with nitrogen-fixing cyanobacteria. The cyanobacteria, Anabaena azollae, lives on the leaves of Azolla and can fix atmospheric nitrogen. This nitrogen-fixing ability increases the fertility of the soil and enhances crop yields.
Azolla is a small aquatic fern that grows on the surface of water or moist soil. It is used as a biofertilizer for rice in Asia. Azolla can be grown as a green manure before transplanting rice or as an intercrop with the rice. Both practices are reported to increase the growth and yield of rice.
Azolla is also used as animal feed, human food, medicine, and water purifier.
9. Which of the following is the characteristic of water present in coconut?
[A] liquid endocarp
[B] liquid nucellus
[C] liquid mesocarp
[D] degenerated liquid endosperm
Show Answer
Correct Answer: D [degenerated liquid endosperm]
Notes:
The coconut water from tender coconut that we are familiar with, is nothing but free nuclear endosperm (made up of thousands of nuclei) and the surrounding white kernel is the cellular endosperm. In the most common types of endosperm development, the Primary Endosperm Nucleus (PEN) undergoes successive.
10. Who among the following analysed the DNA for the first time ?
[A] Watson and Krick
[B] Karl von Frisch
[C] M. W. Nirenberg
[D] Hargobind Khurana
Show Answer
Correct Answer: A [Watson and Krick]
Notes:
The discovery in 1953 of the double helix, the twisted-ladder structure of deoxyribonucleic acid (DNA), by James Watson and Francis Crick marked a milestone in the history of science and gave rise to modern molecular biology, which is largely concerned with understanding how genes control the chemical processes.