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[I] Biology Question Paper With Answers “Zoology 2018 “
1. What is meant by Clone?
Ans: An organism or cell, or group of organisms or cells, produced asexually from one ancestor or stock, to which they are genetically identical.
2. Define the term Apomixes.
Ans: Asexual reproduction is a type of reproduction wherein the offspring comes not from the union of gametes but from other means.
3. How the age of Fossils is calculated?
Ans: Scientists combine several well-tested techniques to find out the ages of fossils.
4. Write the scientific name of microorganisms used to produce ethanol.
5. What is triple fusion? Name the nuclei involved in triple fusion.
Ans: Triple fusion is the fusion of the male gamete with two polar nuclei inside the embryo sac of the angiosperm. One male gamete nucleus and two polar nuclei are involved in this process.
6. Explain any two outbreeding devices that following plants have developed to encourage Cross Pollination.
7. Mention four objects for improving the natural quality of crops by the process of biofortification.
8. What is the totipotency of the cell? What is the importance of totipotency in Plant Science?
Ans: Totipotency is the ability of a single cell to divide and produce all of the differentiated cells in an organism. The totipotentiality of somatic cells has been exploited in vegetative propagation of many economical, medicinal as well as agriculturally important plant species. Therefore, from fundamental to applied aspect of plant biology, cellular totipotency is highly important.
9. Write a brief note on Biochemical Oxygen Demand.
Ans: Biochemical Oxygen Demand (BOD, also called Biological Oxygen Demand) is the amount of dissolved oxygen needed (i.e. demanded) by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. The BOD value is most commonly expressed in milligrams of oxygen consumed per liter of the sample during 5 days of incubation at 20 °C and is often used as a surrogate of the degree of organic pollution of water.
10. What are Antibodies? Name two microorganisms used to produce antibodies.
Ans: A blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances which the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood. Penicillin & Cephalosporin.
11. How the insecticidal proteins act on Pest?
12. Describe briefly about Bioreactors.
Ans: A bioreactor may refer to any manufactured or engineered device or system that supports a biologically active environment. In one case, a bioreactor is a vessel in which a chemical process is carried out which involves organisms or biochemically active substances derived from such organisms. This process can either be aerobic or anaerobic. These bioreactors are commonly cylindrical, ranging in size from liters to cubic meters, and are often made of stainless steel.
13. What is a single cell protein (SCP)? Name two algae used to produce SCP.
Ans: Single-cell proteins are the dried cells of microorganism, which are used as a protein supplement in human foods or animal feeds. Cyanobacteria and Unicellular Eukaryotes.
14. Write an account on the role of microbes in biogas production.
Ans: Microbes usually produce gases during their growth and metabolism. Based on the organic substrates they utilise, different microbes produce different gases. A biogas plant is an effective way to generate energy from wastes through microbial activity. Biogas generated from biogas plants can be used as low-cost fuel that burns without emitting smoke, for lighting streetlights and to run electric engines.
15. Explain Briefly.
Ans: Molecular diagnostic is a collection of techniques used to analyze biological markers in the genome and proteome—the individual’s genetic code and how their cells express their genes as proteins—by applying molecular biology to medical testing.
Ans: Restriction enzymes are molecular scissors that cut DNA into pieces. Find out which enzymes will cut, and whereby making a restriction map. Then you can figure out what will happen if you change the sequence of the DNA.
16. What is Mutualism? Explain Mutualism with suitable examples.
Ans: Mutualism or interspecific cooperation is the way two organisms of different species exist in a relationship in which each individual fitness benefits from the activity of the other. Similar interactions within a species are known as co-operation. Common Examples of Mutualism. Oxpeckers and zebras or rhinos – In this relationship, the oxpecker (a bird) lives on the zebra or rhino, sustaining itself by eating all of the bugs and parasites on the animal.
17. How do biofertilizers enrich the fertility of Soil?
Ans: These are introduced to seeds, roots, or soil to mobilize the availability of nutrients by their biological activity. Thus, they are extremely beneficial in enriching the soil with organic nutrients. … Rhizobium is a symbiotic bacteria found in the root nodules of leguminous plants.
18. Write the scientific names and parts used of following plants.
Ans: The scientific name of Tulsi plant (holy basil) is Ocimum tenuiflorum. It is a plant of medicinal value used in the Ayurvedic system of disease treatment.
Ans: The scientific name of Kalmegh is Andrographis paniculata. Uses of Andrographis. Kalmegh has been used for liver complaints and fever, and as an anti-inflammatory and immunostimulant.
19. Write a note on an adaptation of plants to water scarcity.
Ans: Plants found in deserts are well adapted to cope with water scarcity and scorching heat of the desert. Plants have an extensive root system to tap underground water. They bear thick cuticles and sunken stomata on the surface of their leaves to reduce transpiration. In Opuntia, the leaves are modified into spines and the process of photosynthesis is carried out by green stems. Desert plants have special pathways to synthesize food, called CAM (C4 pathway). It enables their stomata to
20. Discuss the methods of breeding of diseases resistance crops.
Ans: Identification of plants that may be less desirable in other ways, but which carry a useful disease resistance trait, including wild plant lines that often express enhanced resistance.
The crossing of a desirable but disease-susceptible variety to a plant that is a source of resistance.
The growth of breeding candidates in a disease-conducive setting, possibly including pathogen inoculation. Attention must be paid to the specific pathogen isolates, to address variability within a single pathogen species.
Selection of disease-resistant individuals that retain other desirable traits such as yield, quality and including other disease resistance traits.
21. What do genetically modified organism (GMO) do to the food? How do they use to us?
Ans: In a genetic modification (or engineering) of food plants, scientists remove one or more genes from the DNA of another organism, such as a bacterium, virus, animal, or plant and “recombine” them into the DNA of the plant they want to alter. By adding these new genes, genetic engineers hope the plant will express the traits associated with the genes. For example, genetic engineers have transferred genes from a bacterium known as Bacillus thuringiensis or Bt into the DNA of corn. Bt genes express a protein that kills insects, and transferring the genes allows the corn to produce its own pesticide.
[II] Biology Question Paper With Answers “Botany 2018 “
1. ______ cell present in mammalian testes help to nourish sperm.
Ans: Sertoli cells.
2. The genes located in the Y chromosome are called ______.
3. The major reservoir of carbon on earth is _______.
Ans: 1) in rocks (this includes fossil fuels).
2) dissolved in ocean water.
3) as plants, sticks, animals, and soil (which can be lumped together and called the land biosphere).
4) as a climate-warming gas in the atmosphere.
4. Typhoid fever can be confirmed by _______ test.
Ans: Widal test
5. Why sperm contain mitochondria?
6. What are Okazaki fragments?
Ans: An Okazaki fragment is a relatively short fragment of DNA (with no RNA primer at the 5′ terminus) created on the lagging strand during DNA replication.
7. What are the two basic amino acids which are found in the high amount of histone protein?
8. What is a transgenic organism?
Ans: A genetically modified organism is any organism whose genetic material has been altered using genetic engineering techniques.
9. Describe the formation of Placenta during pregnancy.
Ans: The placenta is a flattened circular organ in the uterus of pregnant mammals that nourishes and maintains the fetus through the umbilical cord. This cord is the main link from the fetus to the placenta. Through it, the placenta provides oxygen and nutrients to the growing baby and removes waste products.
10. Why coacervates were called primitive cell?
Ans: Starting from these suppositions, Oparin assumed that in the hot primitive seas organic molecules would gather in small drops, similar to the actual cells. These small drops wrapped up in water molecules are called “coacervates” (from cum acervo = gather together) and were already known before Oparin’s research.
11. Write the applications of DNA fingerprinting.
Ans: DNA fingerprinting is a technique used to identify and analyze the variations in various individuals at the level of DNA. It is based on variability and polymorphism in DNA sequences.
(1) It is used in forensic science to identify potential crime suspects.
(2) It is used to establish paternity and family relationships.
12. What is Amniocentesis? Why does Amniocentesis is banned?
Ans: Amniocentesis is a diagnostic procedure performed on pregnant women that look for genetic and chromosomal abnormalities (birth defects) in the fetus.
As it requires a specialist to perform the test. The report will not show you the 23rd pair of the chromosome, which is known as the sex chromosome. So there you have it.. karyotyping without prenatal sex determination.
13. Define the chromosomal theory of inheritance.
Ans: This theory states that individual genes are found at specific locations on particular chromosomes and that the behavior of chromosomes during meiosis can explain why genes are inherited according to Mendel’s laws
14. What is Red Rata Book? Which endemic animal of Assam is presently listed in Red Data Book.
Ans: Red Data Book is a state document established for documenting rare and endangered species of animals plants, and fungi as well as some local subspecies (such as the Ladoga seal) that exist within the territory of the Russian Federation and its continental shelf and marine economic zone.
Hoolock Gibbon (Hylobates hoolock).
15. Write the difference between.
*Homologous organ and analogous organ.
Ans: Homologous organ:
- They differ morphologically.
- They have a similar internal structure.
- They develop in related organisms.
- Stages in the development are similar.
- They show the superficial resemblance.
- Their internal structure is quite different.
- They develop in unrelated organisms.
- Stages in the development are different.
*Linkage and crossing over.
- Linkage ensures to keep the genes in a chromosome to inherit together.
- The strength of linkage between two genes is inversely proportional to the distance between them in the chromosome.
- The strength of linkage between two genes increases with the decrease in distance between them.
- Linkage ensures the maintenance of parental trait in the offspring.
- Crossing over facilitates the separation of genes present in a chromosome and segregate into different gametes.
- The chance of crossing over between two genes is directly proportional to the distance between them in the chromosome.
- The chance of crossing over between two genes decreases with the decrease in distance between them.
- The chance of crossing increases with an increase in distance between the genes.
*In-situ conversation and Ex-situ conservation.
Ans: In-situ conversation:
- It means onsite conservation.
- It is the conservation of wild species in their natural habitats in order to maintain and recover endangered species.
- It is more dynamic as it involves natural habitats of organisms.
- It provides protection to endangered species against predators.
- It means offsite conservation.
- It is conservation of species in the man-made habitats that imitate the natural habitats of species.
- It is less dynamic as it involves man-made habitats.
- It provides protection against all hostile factors.
*Plasmid DNA and Chromosomal DNA.
Ans: Plasmid DNA:
- It is always double-stranded.
- It is circular.
- It is naked without histone protein.
- It does not carry any vital gene necessary for the cell.
- It may be single stranded or double stranded.
- It is linear or circular.
- It is coated with histone protein.
- It carries vital genes necessary for the cell.
16. Express diagrammatically the various phases of spermatogenesis.
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