Maharashtra Board SSC Class 10 Science 2 Sample Paper Set 2 with Solutions Answers Pdf Download.
Maharashtra Board Class 10 Science 2 Model Paper Set 2 with Solutions
1. (A) Choose the correct option and write its number for the following questions :
Question 1.
When neutron is bombarded on atom of Uranium-235, it absorbs the neutron and converts into ____.
(a) Its isotope Uranium-236
(b) Its isotope Uranium-234
(c) Degrades into components
(d) No effect is observed
Answer:
(a) When neutron is bombarded on atom of Uranium-235, it absorbs the neutron and converts into its isotope Uranium-236.
Question 2.
Non-chordate animals have :
(a) Rod-like notochord
(b) Pharyngeal gill-slits
(c) Nerve cord on ventral side
(d) No effect is observed
Answer:
(c) Non-chordate animals have nerve cord on ventral side.
Question 3.
………. bacteria is used for industrial production of yogurt.
(a) Streptococcus thermophilus
(b) Clostridium
(c) Spirulina
(d) Chlorella
Answer:
(a) Streptococcus thermophilus is used for industrial production of yogurt.
Question 4.
……….. statements is not true for GM crops.
(a) GM crops are developed with desired characters by integrating foreign gene with their genome.
(b) GM crops are low yielding.
(c) GM crops have resistance to diseases, alkalinity, weeds other stresses like cold and drought.
(d) BT Brinjal variety is developed by using the gene isolated from Bacillus thuringiensis.
Answer:
(b) GM crops are low yielding.
Question 5.
Laughter club is a remedy to drive away ……..
(a) Mental stress
(b) Pollution
(c) Earthquake
(d) AIDS
Answer:
(a) Laughter club is a remedy to drive away mental stress.
1. (B) Solve the following questions.
Question 1.
Find odd one out:
Tail bone, wisdom teeth, ear pinna, appendix, heart.
Answer:
Heart, rest other organs are degenerated or underdeveloped, useless organs of organisms which are known as vestigial organs.
Question 2.
Write the correct co-relation-Butterfly : Arthropoda : : Earthworm : ………
Answer:
Annelida.
Question 3.
State whether True or False :
Excess of amino acids obtained from proteins are stored in the body as such.
Answer:
False, Excess of amino acids obtained from proteins are not stored as such in the body they are broken down and the ammonia evolved during the process is eliminated out of the body.
Question 4.
What is asexual reproduction ?
Answer:
Process of formation of new organism by an organism of same species without involvement of gametes is called as asexual reproduction.
Question 5.
What is term for the production of various useful aquatic organisms with the help of water ?
Answer:
Blue revolution.
2. (A) Give scientific reasons. (Any two)
Question 1.
Give reason why now-a-days, excessive, unnecessary and irrational use of modem technology and communication media is becoming a sensitive issue ?
Answer:
A sort of addiction for use of modem technology has led to endanger social health. For example, people spending the time with cell phones for several hours are usually unaware of the surrounding. Physical problems like tiredness, headache, insomnia, forgetfulness, tinnitus, joint pains and problems in vision may arise due to radiation of cell phones. More serious fact is those radiations penetrate the bones of children more effectively than the bones of adults.
Social isolation is on the increase, people are spending more time playing video games, learning how to use new modem technologies, using social networks and they neglect their real life. Habitually, they become self-centered and thereby they may develop problems like autism and selfishness.
Question 2.
Why it is necessary to ban the use of plastic bags ?
Answer:
Plastic is one of the major pollutant in today’s world. It can not be degraded by the micro-oganisms also. It degrades the fertility of soil. It fills rivers, seas and gutters. This may also lead to flood. Hence, plastic must be banned.
Question 3.
Why is earthworm called farmer’s friend ?
Answer:
Earthworm moves through the soil that loosens and aerates the soil. This helps water to reach the roots quickly. Earthworm’s excreta also increases the fertility of soil. They also help in vermicomposting. Thus, they are called farmer’s friend.
2. (B) Solve the following questions. (Any three)
Question 1.
Complete the chart on production of beverages.
| Fruit | Microbe used | Role of microbe used | Name of beverage |
| (i) Caffea arabica | ………………………… | Separating seeds from fruit | Coffee |
| (ii) Theobroma cacao | Candida, Hansenula, Pichia, Saccharomyces | ………………….. | Cocoa |
Answer:
| Fruit | Microbe used | Role of microbe used | Name of beverage |
| (i) Caffea arabica | Lactobacillus brevis | Separating seeds from fruit | Coffee |
| (ii) Theobroma cacao | Candida, Hansenula, Pichia, Saccharomyces | Separating seeds from fruit | Cocoa |
Question 2.
Differentiate between pre-disaster management and post-disaster management.
Answer:
| Pre-disaster Management | Post-disaster Management |
| 1. It includes the complete preparation and planning to face any type of disaster. | It includes management after the disaster. |
| 2. Preparing the action plan through study of various aspects like preventive measures, rehabilitation and reconstruction. | Providing all types of necessary help to victims of disasters. |
| 3. Include identifying the pre-disaster areas. | Quick establishment of help centre. |
| 4. Collecting the data about intensity of disaster and probable sites of disasters through predictive intensity maps and hazard maps respectively. | Categorisation of the help material received from control centre, deliver -ing the material to victims and continuous monitoring of the help. ’ |
Question 3.
Observe the following figure and explain the concept.
Answer:
The figure depicts the concept proposed by Lamarck. He suggested that the activities of the organisms are responsible for their evolution, each animal or plant undergo some changes in its life span and those changes are transferred to the next generation and such changes occur in next subsequent generations too.
Long neck of giraffe is an example of ‘acquired characters’, the neck of giraffe has become too long due to browsing on leaves of tall plants by extending their neck for several generations.
Question 4.
Discuss the objectives of mock drill.
Answer:
Objectives of Mock drill are :
- Studying the response to the disaster.
- Maintaining the coordination between various departments of disaster control.
- Evaluation of own abilities.
- Enhancing the ability of quick response to disaster.
- Reviewing the competency of the planned actions.
- Evaluating the possible errors and risks.
Question 5.
Answer:
3. Solve the following questions. (Any five)
Question 1.
List the characteristics of pre-disaster management.
Answer:
(i) The characteristics of pre-disaster management are :
(a) Identifying the pre-disaster areas.
(b) Collecting the information about intensity of disaster and probable sites of disasters through predictive intensity maps and hazard maps respectively.
(c) Getting special training for disaster management.
(d) Increasing awareness about disaster management among the general public through training programmes and mass media.
Question 2.
Answer the questions that follows :
(a) Who proposed the theory of survival of the fittest ?
(b) Nature has a way of causing organisms that inherit advantageous traits to survive and reproduce more successfully than the ones that do not. This process is known as ……….
(c) As shown in figure below some organisms that share a common ancestor have features that have different functions, but similar structures.
These are known as ……… . Give example.
Answer:
(a) The phrase “survival of the fittest” originated from Darwinian evolutionary theory for describing the mechanism of natural selection.
(b) Natural selection.
(c) Homologous structures, example human hand, cat’s foreleg, flipper of whale and patagium of bat.
Question 3.
Write down the difference between homologous and analogous organs.
Answer:
| Homologous organs | Analogous organs |
| 1. Those organs which are similar in their structure, morphology and anatomy but different in their functions are known as homologous organs. | Those organs which are different in their structure, morphology and anatomy but similar in their functions are known as analogous organs. |
| 2. They are inherited from common ancestors. | They are inherited from different ancestors. |
| 3. They have similar developmental pattern. | They have dissimilar developmental pattern. |
| 4. Limbs of human, flippers of whale and forelimbs of horse are common examples. | Wings of insects, bats and birds are common examples. |
| 5. Leaves of pitcher plant and cactus are homologous in their functions. | Leaves of Opuntia and Peepal are analogous organs in plants. |
Question 4.
Observe the following figure and answer the questions below :
(a) What does the flow chart depict ?
(b) Why the energy in the coal is called as chemical energy ?
(c) Why such plants are known as thermal power plants ?
Answer:
(a) Energy transformation in thermal power plant.
(b) Coal is a fossil fuel formed millions of years ago from plants. The energy stored in the fossil fuels originally came from sunlight. Plants used light energy from the Sun for photosynthesis to make their chemicals. This stored chemical energy was transferred to stored chemical energy in animals that ate the plants. When the living things died, they were gradually buried by layers of rock. They gradually changed into the fossil fuels. Chemical energy is stored in coal. Coal is a hydrocarbon. When coal is burnt its chemical energy comes out in the form of light and heat energy which results in formation of vapours of carbon dioxide (CO2) and water (H2O).
(c) Since thermal energy is used here to generate electrical energy, such power plants are called thermal power plants.
Question 5.
Explain the following concepts in short:
(a) Radially symmetrical body
(b) Asymmetrical body
(c) Bilaterally symmetrical body
Answer:
(a) In radially symmetrical type of body, if imaginary cut passes through central axis but any plane of body, it gives two equal halves. For example : Starfish. In case of this animal, there are five different planes passing through central axis of body through which we can get two equal halves.
(b) In case of asymmetrical body, there is no any such imaginary axis of the body through which we can get two equal halves. For example : Amoeba, Par-amecium, some sponges.
(c) In bilaterally symmetrical type of body, there is only one such imaginary axis of body through which we can get two equal halves. For example : Insects, fishes, frog, birds, human, etc.
Question 6.
Correct the following flow chart and rewrite.
Answer:
Question 7.
Complete the following table taking into account the relation between the entries in three columns:
| Air pollution | Water pollution | Soil pollution | |
| Components | Gases : CO2, CO, Hydrocarbons, Sulphur, NO2, Hydrogen sulphides etc. Solid : dust, ash, carbon, lead, asbestos, etc. |
||
| Source | Industrial wastes, domestic wastes, sewage, chemicals discharged from industries, pesticides used in agriculture. | ||
| Effect | Soil erosion, retarded growth of plants/ crops, Nutritional deficiency etc. |
Answer:
Air pollution
Components
Gases : CO2, CO, Hydrocarbons, Sulphur, NO2,
Hydrogen sulphides etc.
Solid : dust, ash, carbon, lead, asbestos, etc.
Source
Chemical industries and oil refineries. Thermal power stations, paper industries, cloth mills, cement, manufacturing, Dyna mites, stone crushers.
Effect
Impact on human health. Serious effects on respiratory system, effect of plants and animals, acid rains, climate change.
Water pollution
Components
Biotic components: Alage, Virus, Bacteria, Parasite.
Abiotic factors :
Sand, soil, dust, floating particles, precipitates of salts, silver, lead, heavy
metals, (Radioactive substances)
Organic components: Weedicides, pesticides, sewage, etc.
Source
Industrial wastes, domestic wastes, sewage, chemicals discharged from industries, pesticides used in agriculture.
Effect
Epidemics of water-borne diseases in humans. Mortality of aquatic animals. Eutrophication of the water bodies.
Soil pollution
Components
Soil pollutants are different in different regions.
E.g. Near field-inorganic components of insecticides and excess of fertilizers, heavy metals, and other toxic chemicals.
Source
Industrial effluents, house-hold toxic materials, chemical pesticides, biomedical wastes, E-wastes, plastic waste.
Effect
Soil erosion, retarded growths of plants/crops, Nutritional deficiency etc.
Question 8.
Complete the paragraph using proper words:
(Cytoplasm, nucleus, double codon, triplet codon, 20, 18, translation, transportation, transcription, mutation, tRNA, mRNA)
The mRNA formed in …… nucleus comes in It brings in the coded message from DNA. The message contains the codes for amino acids. The code for each amino acid consists of three nucleotides. It is called as ‘……..’. Dr Har Govind Khorana, a scientist of Indian origin has made an important contribution in discovery of triplet codons for ……. amino acids. For this work, he has been awarded with the Nobel Prize in 1968, along with two other scientists. Each mRNA is made up of thousands of triplet codons.
As per the message on mRNA, amino acids are supplied by the ……. For this purpose, tRNA has ‘anticodon’ having complementary sequence to the codon on mRNA. This is called as ‘…….’. The amino acids brought in by tRNA are bonded together by peptide bonds with the help of rRNA. During this process, the ribosome keeps on moving from one end of mRNA to other end by the distance of one triplet codon. This is called as ‘……’. Such many chains come together to form complex proteins. These proteins control various functions in the body of living organisms and their appearance too.
Answer:
The mRNA formed in nucleus comes in cytoplasm. It brings in the coded message from DNA. The message contains the codes for amino acids. The code for each amino acid consists of three nucleotides. It is called as ‘triplet codon’. Dr Har Govind Khorana, a scientist of Indian origin has made an important contribution in discovery of triplet codons for 20 amino acids.
For this work, he has been awarded with the Nobel Prize in 1968, along with two other scientists. Each mRNA is made up of thousands of triplet codons. As per the message on mRNA, amino acids are supplied by the tRNA. For this purpose, tRNA has ‘anticodon’ having complementary sequence to the codon on mRNA. This is called as ‘translation’.
The amino acids brought in by tRNA are bonded together by peptide bonds with the help of rRNA. During this process, the ribosome keeps on moving from one end of mRNA to other end by the distance of one triplet codon. This is called as ‘translocation’. Such many chains come together to form complex proteins. These proteins control various functions in the body of living organisms and their appearance too.
4. Solve the following questions. (Any one)
Question 1.
Observe the figure and label it properly :
(a) What is the figure related to ?
(b) Why are reflectors used ?
(c) Draw a flow chart showing different stages in such process.
(d) How is the process used to generate electricity ?
(e) What other method can be used to generate electricity using same energy source ?
Answer:
(a) The figure is related to schematic diagram of solar thermal power plant.
(b) Many reflectors reflect and concentrate solar radiation on absorbers.
(c)
(d) The energy in solar radiation is converted into thermal energy first. Then a turbine- generator system is driven using that thermal energy to generate electricity.
(e) Sblar photovoltaic cell converts the solar radiation energy directly into electrical ” energy. This is called solar photovoltaic effect. The electrical energy generated through this energy transformation process is DC in nature.
Question 2.
(a) What is asexual reproduction ?
(b) What is the structural unit of the sexual reproduction in plant ?
(c) What is pollination ?
(d) What are the agents for pollination ?
(e) What is the function of calyx ?
Answer:
(a) Process of formation of new organism by an organism of same species without the involvement of gametes is called as asexual reproduction.
(b) Flower is the structural unit of the sexual reproduction in plant.
(c) The process where pollen grains from anther are transferred to the stigma is called as pollination.
(d) Wind, water, insects and other animals are the agents of the pollination.
(e) The main function of calyx is to protect the inner whorls of the flower.